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  Subjects -> VETERINARY SCIENCE (Total: 213 journals)
Showing 1 - 63 of 63 Journals sorted alphabetically
Acta Scientiae Veterinariae     Open Access   (Followers: 1)
Acta Veterinaria     Open Access   (Followers: 1)
Acta Veterinaria Brasilica     Open Access  
Acta Veterinaria Hungarica     Full-text available via subscription   (Followers: 2)
Acta Veterinaria Scandinavica     Open Access   (Followers: 1)
Advances in Animal Biosciences     Full-text available via subscription   (Followers: 9)
Advances in Small Animal Medicine and Surgery     Hybrid Journal  
Advances in Veterinary Medicine     Full-text available via subscription   (Followers: 12)
Advances in Veterinary Science and Comparative Medicine     Full-text available via subscription   (Followers: 12)
African Journal of Wildlife Research     Full-text available via subscription   (Followers: 1)
Alexandria Journal of Veterinary Sciences     Open Access  
American Journal of Animal and Veterinary Sciences     Open Access   (Followers: 8)
American Journal of Primatology     Hybrid Journal   (Followers: 11)
American Journal of Veterinary Research     Full-text available via subscription   (Followers: 21)
Anatomia, Histologia, Embryologia: Journal of Veterinary Medicine Series C     Hybrid Journal   (Followers: 3)
Animal Behaviour     Hybrid Journal   (Followers: 101)
Animal Feed Science and Technology     Hybrid Journal   (Followers: 5)
Animal Health Research Reviews     Hybrid Journal   (Followers: 3)
Animal Nutrition     Open Access   (Followers: 7)
Animal Reproduction     Open Access   (Followers: 1)
Animal Reproduction Science     Hybrid Journal   (Followers: 4)
Animals     Open Access   (Followers: 6)
Annals of Agricultural and Environmental Medicine     Open Access   (Followers: 1)
Annual Review of Animal Biosciences     Full-text available via subscription   (Followers: 4)
Anthrozoos : A Multidisciplinary Journal of The Interactions of People & Animals     Hybrid Journal   (Followers: 6)
Archives of Animal Nutrition     Hybrid Journal   (Followers: 6)
Archivos de Medicina Veterinaria     Open Access   (Followers: 1)
Arquivo Brasileiro de Medicina Veterinária e Zootecnia     Open Access  
Arquivos de Ciências Veterinárias e Zoologia da UNIPAR     Open Access  
Ars Veterinaria     Open Access  
Asian Journal of Medical and Biological Research     Open Access   (Followers: 1)
Asian Journal of Poultry Science     Open Access   (Followers: 4)
Atatürk Üniversitesi Veteriner Bilimleri Dergisi     Open Access  
Australian Equine Veterinarian     Full-text available via subscription   (Followers: 3)
Australian Veterinary Journal     Hybrid Journal   (Followers: 15)
Avances en Ciencias Veterinarias     Open Access  
Avian Diseases     Full-text available via subscription   (Followers: 3)
Avian Pathology     Hybrid Journal   (Followers: 2)
Bangladesh Journal of Animal Science     Open Access  
Bangladesh Journal of Veterinary Medicine     Open Access   (Followers: 1)
Bangladesh Veterinarian     Open Access  
BMC Veterinary Research     Open Access   (Followers: 10)
Brazilian Journal of Veterinary Research and Animal Science     Open Access   (Followers: 8)
Buletin Peternakan : Bulletin of Animal Science     Full-text available via subscription  
Buletin Veteriner Udayana     Open Access  
Bulletin of Animal Health and Production in Africa     Full-text available via subscription   (Followers: 1)
Bulletin of the Veterinary Institute in Pulawy     Open Access  
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca : Food Science and Technology     Open Access  
Canadian Journal of Veterinary Research     Full-text available via subscription   (Followers: 8)
Case Reports in Veterinary Medicine     Open Access   (Followers: 5)
Ciência Animal Brasileira     Open Access  
Ciência Rural     Open Access  
Cogent Food & Agriculture     Open Access  
Companion Animal     Full-text available via subscription   (Followers: 8)
Domestic Animal Endocrinology     Hybrid Journal   (Followers: 4)
Equine Health     Full-text available via subscription   (Followers: 3)
Equine Veterinary Education     Hybrid Journal   (Followers: 9)
Equine Veterinary Journal     Hybrid Journal   (Followers: 13)
Ethiopian Veterinary Journal     Open Access   (Followers: 5)
Eurasian Journal of Veterinary Sciences     Open Access   (Followers: 1)
FAVE Sección Ciencias Veterinarias     Open Access  
Frontiers in Veterinary Science     Open Access   (Followers: 1)
Global Journal of Animal Scientific Research     Open Access   (Followers: 1)
Human & Veterinary Medicine - International Journal of the Bioflux Society     Open Access   (Followers: 5)
ILAR Journal     Hybrid Journal  
In Practice     Full-text available via subscription   (Followers: 2)
Indian Journal of Animal Sciences     Open Access   (Followers: 4)
Indian Journal of Veterinary Anatomy     Full-text available via subscription   (Followers: 4)
Indonesia Medicus Veterinus     Open Access  
Intas Polivet     Full-text available via subscription  
International Journal for Agro Veterinary and Medical Sciences     Open Access   (Followers: 2)
International Journal of Livestock Research     Open Access  
International Journal of Veterinary Science and Medicine     Open Access   (Followers: 4)
Iranian Journal of Applied Animal Science     Open Access  
Irish Veterinary Journal     Open Access   (Followers: 5)
İstanbul Üniversitesi Veteriner Fakültesi Dergisi     Open Access  
Journal of Veterinary Science & Technology     Open Access   (Followers: 6)
Journal of Advanced Veterinary and Animal Research     Open Access   (Followers: 5)
Journal of Animal Behaviour and Biometeorology     Open Access   (Followers: 1)
Journal of Animal Physiology and Animal Nutrition     Hybrid Journal   (Followers: 5)
Journal of Animal Science and Technology     Open Access  
Journal of Applied Animal Nutrition     Hybrid Journal   (Followers: 3)
Journal of Avian Medicine and Surgery     Full-text available via subscription   (Followers: 5)
Journal of Buffalo Science     Hybrid Journal  
Journal of Equine Veterinary Science     Hybrid Journal   (Followers: 11)
Journal of Exotic Pet Medicine     Full-text available via subscription   (Followers: 3)
Journal of Experimental and Applied Animal Sciences     Open Access   (Followers: 1)
Journal of Feline Medicine & Surgery     Hybrid Journal   (Followers: 4)
Journal of Research in Forestry, Wildlife and Environment     Open Access   (Followers: 3)
Journal of Small Animal Practice     Hybrid Journal   (Followers: 11)
Journal of the American Veterinary Medical Association     Full-text available via subscription   (Followers: 27)
Journal of the Selva Andina Research Society     Open Access  
Journal of the South African Veterinary Association     Open Access   (Followers: 2)
Journal of Venomous Animals and Toxins     Open Access   (Followers: 4)
Journal of Veterinary Advances     Open Access   (Followers: 4)
Journal of Veterinary Behavior: Clinical Applications and Research     Hybrid Journal   (Followers: 4)
Journal of Veterinary Cardiology     Full-text available via subscription   (Followers: 7)
Journal of Veterinary Diagnostic Investigation     Hybrid Journal   (Followers: 8)
Journal of Veterinary Emergency and Critical Care     Hybrid Journal   (Followers: 15)
Journal of Veterinary Internal Medicine     Open Access   (Followers: 19)
Journal of Veterinary Medical Education     Partially Free   (Followers: 11)
Journal of Veterinary Medicine     Open Access   (Followers: 8)
Journal of Veterinary Medicine and Animal Health     Open Access   (Followers: 4)
Journal of Veterinary Pharmacology and Therapeutics     Hybrid Journal   (Followers: 8)
Journal of Veterinary Science & Medical Diagnosis     Hybrid Journal   (Followers: 4)
Journal of Zoo and Aquarium Research     Open Access   (Followers: 2)
Journal of Zoo and Wildlife Medicine     Full-text available via subscription   (Followers: 5)
Jurnal Agripet     Open Access  
Kenya Veterinarian     Full-text available via subscription   (Followers: 2)
kleintier konkret     Hybrid Journal  
Livestock     Full-text available via subscription   (Followers: 1)
Macedonian Veterinary Review     Open Access   (Followers: 2)
MEDIA PETERNAKAN - Journal of Animal Science and Technology     Open Access   (Followers: 1)
Medical Mycology     Open Access   (Followers: 3)
Medical Mycology Case Reports     Open Access  
Microbes and Health     Open Access   (Followers: 1)
New Zealand Veterinary Journal     Full-text available via subscription   (Followers: 11)
New Zealand Veterinary Nurse     Full-text available via subscription   (Followers: 3)
Nigerian Veterinary Journal     Open Access  
Nutrición Animal Tropical     Open Access   (Followers: 1)
Onderstepoort Journal of Veterinary Research     Open Access   (Followers: 3)
Open Access Animal Physiology     Open Access   (Followers: 4)
Open Journal of Animal Sciences     Open Access   (Followers: 4)
Open Journal of Veterinary Medicine     Open Access   (Followers: 4)
Pesquisa Veterinária Brasileira     Open Access  
pferde spiegel     Hybrid Journal  
Polish Journal of Veterinary Sciences     Open Access   (Followers: 3)
Pratique Médicale et Chirurgicale de l'Animal de Compagnie     Full-text available via subscription  
Preventive Veterinary Medicine     Hybrid Journal   (Followers: 10)
REDVET. Revista Electrónica de Veterinaria     Open Access  
Reproduction in Domestic Animals     Hybrid Journal   (Followers: 1)
Research & Reviews : Journal of Veterinary Science and Technology     Full-text available via subscription   (Followers: 1)
Research in Veterinary Science     Hybrid Journal   (Followers: 10)
Research Journal of Veterinary Sciences     Open Access   (Followers: 8)
Revista Brasileira de Ciência Veterinária     Open Access  
Revista Brasileira de Higiene e Sanidade Animal     Open Access  
Revista Brasileira de Parasitologia Veterinaria     Open Access  
Revista Brasileira de Reprodução Animal     Open Access  
Revista Brasileira de Zootecnia     Open Access   (Followers: 2)
Revista Ciencia Animal     Open Access  
Revista Ciencias Veterinarias     Open Access  
Revista Científica     Open Access  
Revista Colombiana de Ciencias Pecuarias (Colombian journal of animal science and veterinary medicine)     Open Access   (Followers: 1)
Revista Complutense de Ciencias Veterinarias     Open Access  
Revista da Sociedade Brasileira de Ciência em Animais de Laboratório     Open Access  
Revista de Ciências Agroveterinárias     Open Access  
Revista de Educação Continuada em Medicina Veterinária e Zootecnia     Open Access  
Revista de Investigaciones Veterinarias del Perú     Open Access  
Revista de la Facultad de Medicina Veterinaria y de Zootecnia     Open Access   (Followers: 1)
Revista de Medicina Veterinaria     Open Access  
Revista de Salud Animal     Open Access  
Revista Mexicana de Ciencias Pecuarias     Open Access  
Revista MVZ Córdoba     Open Access  
Revista Veterinaria     Open Access  
Revue Marocaine des Sciences Agronomiques et Vétérinaires     Open Access  
SA Stud Breeder / SA Stoetteler     Full-text available via subscription  
Schweizer Archiv für Tierheilkunde     Hybrid Journal  
Scientific Journal of Animal Science     Open Access   (Followers: 3)
Scientific Journal of Veterinary Advances     Open Access   (Followers: 1)
Small Ruminant Research     Hybrid Journal   (Followers: 2)
Sokoto Journal of Veterinary Sciences     Open Access   (Followers: 1)
Spei Domus     Open Access  
Tanzania Veterinary Journal     Full-text available via subscription   (Followers: 1)
team.konkret     Open Access  
The Dairy Mail     Full-text available via subscription   (Followers: 3)
Theriogenology     Hybrid Journal   (Followers: 1)
Topics in Companion Animal Medicine     Hybrid Journal   (Followers: 3)
Transboundary and Emerging Diseases     Hybrid Journal   (Followers: 2)
Trends in Animal and Veterinary Sciences     Open Access   (Followers: 5)
Trends in Parasitology     Full-text available via subscription   (Followers: 9)
Tropical Animal Health and Production     Hybrid Journal  
Tropical Veterinarian     Full-text available via subscription   (Followers: 1)
Turkish Journal of Veterinary and Animal Sciences     Open Access  
veterinär spiegel     Hybrid Journal   (Followers: 1)
Veterinária e Zootecnia     Open Access  
Veterinária em Foco     Open Access  
Veterinaria México     Open Access  
Veterinária Notícias     Open Access  
Veterinary Anaesthesia and Analgesia     Hybrid Journal   (Followers: 11)
Veterinary and Comparative Oncology     Hybrid Journal   (Followers: 7)
Veterinary Clinical Pathology     Hybrid Journal   (Followers: 9)
Veterinary Clinics of North America: Equine Practice     Full-text available via subscription   (Followers: 9)
Veterinary Clinics of North America: Exotic Animal Practice     Full-text available via subscription   (Followers: 7)
Veterinary Clinics of North America: Food Animal Practice     Full-text available via subscription   (Followers: 5)
Veterinary Clinics of North America: Small Animal Practice     Full-text available via subscription   (Followers: 15)
Veterinary Dermatology     Hybrid Journal   (Followers: 7)
Veterinary Immunology and Immunopathology     Hybrid Journal   (Followers: 10)
Veterinary Journal     Hybrid Journal   (Followers: 15)
Veterinary Medicine and Animal Sciences     Open Access   (Followers: 3)
Veterinary Medicine and Science     Open Access  
Veterinary Medicine International     Open Access   (Followers: 7)
Veterinary Medicine: Research and Reports     Open Access   (Followers: 4)
Veterinary Microbiology     Hybrid Journal   (Followers: 8)
Veterinary Nurse     Full-text available via subscription   (Followers: 3)
Veterinary Nursing Journal     Hybrid Journal   (Followers: 3)
Veterinary Ophthalmology     Hybrid Journal   (Followers: 6)
Veterinary Parasitology     Hybrid Journal   (Followers: 9)
Veterinary Pathology     Full-text available via subscription   (Followers: 14)
Veterinary Quarterly     Hybrid Journal   (Followers: 3)
Veterinary Radiology & Ultrasound     Hybrid Journal   (Followers: 12)

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Journal Cover Domestic Animal Endocrinology
  [SJR: 0.882]   [H-I: 53]   [4 followers]  Follow
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0739-7240
   Published by Elsevier Homepage  [2970 journals]
  • Transcript levels of genes implicated in steroidogenesis in the testes and
           fat tissue in relation with androstenone accumulation in fat of pubertal
    • Abstract: Publication date: Available online 9 April 2016
      Source:Domestic Animal Endocrinology
      Author(s): A. Robic, K. Feve, J. Riquet, A. Prunier
      The present study was performed to measure mRNA levels of steroidogenic enzymes in testes and fat tissue and determine whether they are related to fat androstenone level. Real time PCR experiments were performed on 26 testes and 12 adipose tissue samples from pubertal boars using 21 genes. The absence of significant correlations between fat androstenone and the transcriptional activity of the SRD5A2 and SRD5A3 genes but the high correlation coefficient with that of the SRD5A1 gene (r = 0.62, P < 0.05) suggest that the enzyme coded by SRD5A1 is mainly responsible for the last step of androstenone synthesis. The testicular transcriptional activities of CYP17, CYP11A1, CYP19A, AKR1C-pig6, SRD5A1, LHCGR, and AR were significantly correlated. Only transcriptional levels of CYP17, CYP11A1, CYP19A, SRD5A1 and AKR1C-pig6 were correlated with the fat concentration of androstenone (0.57 < r < 0.70, P < 0.05) confirming that the amount of androstenone stored in fat is related to the production in testes of androstenone and more generally to all sex steroids. Altogether, our data are in favor of a preponderant role of AKR1C-pig6 instead of HSD17B3 for testicular synthesis of steroids. Concerning fat tissue, our data do not support a significant de novo biosynthesis of steroids in porcine adipose tissues. The presence of transcripts coding for steroid enzymes, especially those of AKR1C-pig6, suggests that steroids can be transformed. None of transcript abundance was related to androstenone accumulation (P > 0.1). Therefore, steroids synthesized elsewhere can be transformed in fat tissue but synthesis of androstenone is unlikely.

      PubDate: 2016-04-09T14:44:46Z
  • Endocrine regulation of gut maturation in early life in pigs
    • Abstract: Publication date: Available online 7 April 2016
      Source:Domestic Animal Endocrinology
      Author(s): T. Thymann
      Following birth the newborn must adapt to the acute challenges of circulatory changes, active respiration, thermoregulation, microbial colonization, and enteral nutrition. Whereas these processes normally occur without clinical complications in neonates born at term, birth at a preterm state of gestation is associated with high morbidity and mortality. In commercial pig production, perinatal mortality is higher than in any other mammalian species. Asphyxia, hypothermia, hypoglycemia, sepsis and gut dysmotility, represent some of the most common findings. The intestine is a particularly sensitive organ after birth, as it must adapt acutely to enteral nutrition and microbial colonization. Likewise, during the weaning phase, the intestine must adapt to new diets types. Both critical phases are associated with high morbidity. This review focuses on the endocrine changes occurring around birth and weaning. There are a number of endocrine adaptations in late gestation and early postnatal life that are under influence of stage of development and environmental factors such as diet. The review discusses general endocrine changes in perinatal life, but specifically focuses on the role of Glucagon-Like Peptide -2 (GLP-2). This gut-derived hormone plays a key role in development and function of the intestine in early life.

      PubDate: 2016-04-09T14:44:46Z
  • Early pregnancy in the mare: old concepts re-visited
    • Abstract: Publication date: Available online 1 April 2016
      Source:Domestic Animal Endocrinology
      Author(s): C. Klein
      “Maternal recognition of pregnancy” (MRP) is commonly used to describe the ongoing embryo-maternal communication during early pregnancy that culminates in prevention of luteolysis and ensures ongoing progestin support. The conceptus-derived pregnancy recognition signal has not yet been identified in the mare. Although equine conceptuses produce substantial amounts of estrogens, there is a lack of evidence that estrogens are the pregnancy recognition signal in mares. Conceptus mobility is integral to MRP and is driven by conceptus-derived prostaglandin production. Cessation of conceptus mobility, referred to as fixation, is caused by increases in conceptus size and uterine tone, and reduction in sialic acid content of the embryonic capsule. Gene expression profiling of equine pre-implantation conceptuses revealed expression of neuraminidase 2 (NEU2), an enzyme that cleaves sialic acid from polysaccharide chains. Furthermore, secretion of NEU2 by conceptuses in vitro was functionally active; it appears therefore, that the conceptus itself regulates sialic acid content through expression of NEU2. Based on gene expression profiling, equine conceptuses express increasing amounts of fibrinogen during early development. Western blot analysis confirmed secretion of fibrinogen into culture medium when conceptuses were cultured in vitro and with immunohistochemistry, the acellular glycoprotein capsule of the conceptus had particularly intense staining for fibrinogen. Therefore, we hypothesize that conceptus-derived fibrinogen interacts with endometrial integrins to promote cessation of conceptus mobility and fixation. Indeed, next generation sequencing analysis of conceptus and endometrial samples 16 d after ovulation revealed the integrin signaling pathway is significantly enriched in both sample types. Real-time RT-PCR confirmed ITGAVB1 as the most abundant integrin receptor in endometrium; fibrinogen has the highest affinity for ITGAVB1 amongst integrins receptors to which it binds. Lastly, the equine conceptus expresses increasing quantities of relaxin during pre-implantation development, with the endometrium expressing relaxin receptors. In the pig, mouse and human, relaxin is produced by the corpus luteum and is known to promote angiogenesis during early pregnancy. In summary, substantial advances in understanding MRP in the horse are underway.

      PubDate: 2016-04-06T14:37:11Z
  • Stress, cortisol and obesity: a role for cortisol responsiveness in
           identifying individuals prone to obesity
    • Abstract: Publication date: Available online 31 March 2016
      Source:Domestic Animal Endocrinology
      Author(s): S.D. Hewagalamulage, T.K. Lee, I.J. Clarke, B.A. Henry
      There is a strong inter-relationship between activation of the hypothalamo-pituitary adrenal axis and energy homeostasis. Patients with abdominal obesity have elevated cortisol levels. Furthermore, stress and glucocorticoids act to control both food intake and energy expenditure. In particular, glucocorticoids are known to increase the consumption of foods enriched in fat and sugar. It is well known that, in all species, the cortisol response to stress or adrenocorticotropin is highly variable. It has now emerged, that cortisol responsiveness is an important determinant in the metabolic sequelae to stress. Sheep that are characterised as high cortisol responders (HR) have greater propensity to weight gain and obesity than low cortisol responders (LR). This difference in susceptibility to become obese is associated with a distinct metabolic, neuroendocrine and behavioral phenotype. In women and ewes, HR individuals eat more in response to stress than LR. Furthermore, HR sheep have impaired melanocortin signalling and reduced skeletal muscle thermogenesis. HR sheep exhibit reactive coping strategies, whereas LR exhibit proactive coping strategies. This complex set of traits leads to increased food intake and reduced energy expenditure in HR and thus predisposition to obesity. We predict that cortisol responsiveness may be used as a marker to identify individuals that are at risk of weight gain and subsequent obesity.

      PubDate: 2016-04-01T21:46:17Z
  • The role of mitochondrial DNA copy number, variants and haplotypes in farm
           animal developmental outcome
    • Abstract: Publication date: Available online 31 March 2016
      Source:Domestic Animal Endocrinology
      Author(s): Tesha Tsai, Justin C. St. John
      The vast majority of cellular energy is generated through the process of oxidative phosphorylation, which takes place in the electron transfer chain in the mitochondria. The ETC is encoded by two genomes, the chromosomal and the mitochondrial (mtDNA) genomes. MtDNA is associated with a number of traits, which include tolerance to heat, growth and physical performance, meat and milk quality and fertility. Mitochondrial genomes can be clustered into groups known as mtDNA haplotypes. MtDNA haplotypes are a potential genetic source for manipulating phenotypes in farm animals. The use of assisted reproductive technologies, such as nuclear transfer, allow favourable chromosomal genetic traits to be mixed and matched with sought after mtDNA haplotype traits. As a result super breeds can be generated.

      PubDate: 2016-04-01T21:46:17Z
  • Influence of blanketing and season on vitamin D and parathyroid hormone,
    • Abstract: Publication date: Available online 19 March 2016
      Source:Domestic Animal Endocrinology
      Author(s): S. Azarpeykan, K.E. Dittmer, E.K. Gee, J.C. Marshall, J. Wallace, P. Elder, E. Acke, K.G. Thompson
      The aims of the study were to determine effect of season and blanketing on vitamin D synthesis in horses, and examine the interaction between vitamin D and other analytes involved in calcium homeostasis. Twenty-one healthy horses at pasture were included; 5 were covered with standard horse blankets including neck rugs. Blood samples were collected for 13 mo and analyzed for 25-hydroxyvitamin D2 (25OHD2), and 25-hydroxyvitamin D3 (25OHD3), 1,25-dihydroxyvitamin D (1,25(OH)2D), ionized calcium (iCa), total calcium (tCa), phosphorus (P), total magnesium (tMg) and parathyroid hormone (PTH). Grass and hay samples were collected and analyzed for vitamin D, calcium, phosphorus and magnesium. Climate data were also collected. The serum concentration of 25OHD3 in horses either undetectable or below the detection limit of the assay, and the main form of 25OHD was 25OHD2. No differences in serum 25OHD2, 1,25(OH)2D, iCa, tCa, P, tMg and PTH (P ≥ 0.05) concentrations were seen between the 2 groups. Associations were seen between iCa and PTH (P < 0.05), iCa and tMg (P < 0.05) and dietary vitamin D and 25OHD2 (P < 0.05). A strong seasonal trend was seen in serum 25OHD2 (P < 0.0001) which was higher during spring and summer when the amount of sunshine and UV radiation was higher. Parathyroid hormone and 1,25(OH)2D showed opposing trends with PTH higher in winter while 1,25(OH)2D was higher in summer. The results suggest that dietary vitamin D maybe necessary for horses to fulfill their vitamin D requirements, however further research is required to determine the contribution of vitamin D3 synthesis in the skin to the vitamin D status of the horse.

      PubDate: 2016-03-23T19:29:13Z
  • Characteristics and functions of a minor FSH surge near the end of an
           interovulatory interval in Bos taurus heifers
    • Abstract: Publication date: Available online 17 March 2016
      Source:Domestic Animal Endocrinology
      Author(s): O.J. Ginther, J.M. Baldrighi, M.A.R. Siddiqui, C.A. Wolf
      The apparent function of a minor FSH surge based on temporality with follicular events was studied in 10 heifers with 2 follicular waves per interovulatory interval. Individual follicles were tracked from their emergence at 2 mm until their outcome was known and a blood sample was collected for FSH and LH assay every 12 h from Day −14 (Day 0 = ovulation) to Day 4. A minor FSH surge occurred in each heifer (peak, Day −4.6 ± 0.2). Concentration of LH increased (P < 0.05) during the FSH increase of the minor surge but did not decrease during the FSH decrease. A minor follicular wave with 8.2 ± 2.0 follicles occurred in 6 of 10 heifers. The maximal diameter (mean, 3.4 ± 0.9 mm) of 77% of the minor-wave follicles occurred in synchrony on Day −4.4 ± 0.4. Most (59%) of minor wave follicles regressed before ovulation and 41% decreased and then increased in diameter (recovered) on Day −1.9 ± 0.3 to become part of the subsequent wave 1. A mean of 3.7 ± 0.9 regressing subordinate follicles from wave 2 recovered on the day before or at the peak of the minor FSH surge. The growth rate of the preovulatory follicle decreased (P < 0.02) for 3 d before the peak of the minor FSH surge and then increased (P < 0.03). Concentration of LH increased slightly but significantly temporally with the resurgence in growth rate of the preovulatory follicle. A minor LH surge peaked (P < 0.0002) on Day 3 at the expected deviation in growth rates between the future dominant and subordinate follicles. Results indicated on a temporal basis that the recovery of some regressing subordinate follicles of wave 2 was attributable to the minor FSH surge. The hypothesis was supported that some regressing follicles from the minor follicular wave recover to become part of wave 1.

      PubDate: 2016-03-19T18:43:07Z
  • Assessment of caprine corpora lutea growth, progesterone concentration and
           eNOS expression: Effect of a compensatory gain model
    • Abstract: Publication date: Available online 8 March 2016
      Source:Domestic Animal Endocrinology
      Author(s): J. Thammasiri, C. Navanukraw, S. Uriyapongson, V. Khanthusaeng, K. Lertchunhakiat, S. Boonkong
      The experiment was conducted to evaluate corpus luteum (CL) growth, progesterone (P4) concentration and endothelial nitric oxide synthase (eNOS) expression in nutrient stair-step fed goats. Female goats (n = 32) that exhibited at least two, normal, consecutive estrous cycles were randomly assigned to either the control or stair-step fed group. In the control group, goats were fed ad libitum (100% of nutrient requirement for goats). The goats in the stair-step group were fed 70% of the control consumption for the first 42 d and 130% for the later 42 d during four consecutive estrous cycles (84 d). Blood and luteal samples were collected on days 3, 8, 13, 18 of the estrous cycle to determine concentration of glucose, insulin, P4, luteal growth, and eNOS expression. Luteal growth was determined using fresh CL weight, DNA content, DNA and protein concentrations, and cell proliferation (labeling index of Ki67). During realimentation phase at 4 h, glucose and insulin concentrations were greater (P < 0.05) in stair-step fed goat than control goats. Fresh CL weight, DNA content, protein concentrations and labeling index of Ki67 on day 8 of the estrous cycle in the stair-step group were greater (P < 0.05) than that of the control group. Protein for eNOS was located in the capillaries of CL throughout of the estrous cycle in both groups. Greater serum P4 concentrations and eNOS protein (P < 0.05) were observed in the stair-step fed goats on day 3 (1.83 ng/mL and 6.79%) compared to the control goats (0.98 ng/mL and 6.02%), and on day 8 (5.15 ng/mL and 7.88%) compared to the control goats (4.54 ng/mL and 7.07%). These data demonstrate that luteal growth, progesterone concentration, and eNOS protein were partially affected by nutrient compensatory gain in goats.

      PubDate: 2016-03-10T17:27:29Z
  • Marine macroalgal extracts to maintain gut homeostasis in the weaning
    • Abstract: Publication date: Available online 3 March 2016
      Source:Domestic Animal Endocrinology
      Author(s): T. Sweeney, J.V. O’Doherty
      The mammalian gastrointestinal tract is a dynamic environment, where a symbiotic relationship exists between the resident microbiota and the digestive and immune systems of the host. The development of the immune system begins in-utero and is further developed following the colonization of the GIT with microbiota during birth and postnatal life. The early establishment of this relationship is fundamental to the development and long-term maintenance of gut homeostasis. Regulatory mechanisms ensure an appropriate level of immune reactivity in the gut to accommodate the presence of beneficial and dietary microorganisms, while allowing effective immune responses to clear pathogens. However, unfavorable alterations in the composition of the microbiota, known as dysbiosis, have been implicated in many conditions including post-weaning diarrhea in pigs. Weaning is a major critical period in pig husbandry. It involves complex dietary, social and environmental stresses that interfere with gut development. Post-weaning complications in piglets are characterized by a reduction in feed intake and growth, atrophy of small intestine architecture, up-regulation of intestinal inflammatory cytokines, alterations in GIT microflora, diarrhea, and heightened susceptibility to infection. These challenges have been controlled with in-feed prophylactic antibiotics and dietary minerals. However, these strategies are under scrutiny because of their role in promoting multi-drug resistant bacteria and the accumulation of minerals in the environment, respectively. Therefore, significant efforts are being made to identify natural alternatives to support homeostasis in the piglet GIT, in particular during the weaning period. Chemodiversity in nature, including microorganisms, terrestrial plants, seaweeds and marine organisms, offers a valuable source for novel bioactives. In this review, we discuss the advances in our understanding of the immune mechanisms by which the dynamic interplay of the intestinal microbiota and its host normally favours a homeostatic, symbiotic relationship, and how feeding macroalgal bioactives in both the maternal diet and the piglet diet, can be utilized to support this symbiotic relationship in times of challenge.

      PubDate: 2016-03-05T16:53:21Z
  • Dynamics of L cells along the crypt-villous axis in the chicken ileum
    • Abstract: Publication date: Available online 3 March 2016
      Source:Domestic Animal Endocrinology
      Author(s): K. Nishimura, K. Hiramatsu, T. Watanabe
      The dynamics of L cells along the crypt-villous axis were investigated in the ileum of male White Leghorn chicks (7 d of age, n=5). Immunohistochemistry was used to detect the expression of glucagon-like peptide (GLP)-1 and an in situ hybridization technique to detect proglucagon mRNA. Immunocytochemistry using colloidal gold was also applied to quantitatively evaluate the GLP-1 content. The cells expressing a proglucagon mRNA signal were distributed mainly in the crypts and the bottom of the villi, but were never found in the upper part of the villi. Most of the cells expressing a proglucagon mRNA signal (97%) were immunoreactive for GLP-1 antiserum. In contrast, GLP-1 immunoreactive cells were distributed from the crypts to the middle part of the villi, and only 55% of them expressed a proglucagon mRNA signal. Quantitative evaluation by immunocytochemistry of GLP-1 using colloidal gold revealed that the GLP-1 content was significantly lower in L cells located in the villous epithelium than that of L cells located in the crypts (p<0.01). These findings indicate that L cells in the chicken ileum mature and complete GLP-1 production in the crypts. L cells in the villous epithelium secrete GLP-1, but do not synthesize this peptide.

      PubDate: 2016-03-05T16:53:21Z
  • Cattle temperament influences metabolism: Metabolic response to glucose
           tolerance and insulin sensitivity tests in beef steers†,‡
    • Abstract: Publication date: Available online 4 March 2016
      Source:Domestic Animal Endocrinology
      Author(s): N.C. Burdick Sanchez, J.A. Carroll, P.R. Broadway, H.D. Hughes, S.L. Roberts, J.T. Richeson, T.B. Schmidt, R.C. Vann
      Cattle temperament, defined as the reactivity of cattle to humans or novel environments, can greatly influence several physiological systems in the body, including immunity, stress, and most recently discovered, metabolism. Greater circulating concentrations of non-esterified fatty acids (NEFAs) found in temperamental cattle suggests that temperamental cattle are metabolically different than calm cattle. Further, elevated NEFA concentrations have been reported to influence insulin sensitivity. Therefore, the objective of this study was to determine whether cattle temperament would influence the metabolic response to a glucose tolerance test (GTT) and insulin sensitivity test (IST). Angus-cross steers (16 Calm and 15 Temperamental; 216 ± 6 kg BW) were selected based on Temperament Score measured at weaning. On day 1, steers were moved into indoor stanchions to allow measurement of individual ad libitum feed intake. On day 6, steers were fitted with indwelling rectal temperature probes and jugular catheters. At 0900 h on day 7, steers received the GTT (0.5 mL/kg BW of a 50% dextrose solution) and at 1400 h on day 7, steers received the IST (2.5 IU bovine insulin/kg BW). Blood samples were collected and serum isolated at -60, -45, -30, -15, 0, 10, 20, 30, 45, 60, 90, 120, and 150 min relative to each challenge. Serum was stored at -80oC until analyzed for cortisol, glucose, NEFA, and blood urea nitrogen (BUN) concentrations. All variables changed over time (P < 0.01). For the duration of the study, Temperamental steers maintained greater (P < 0.01) serum NEFA and less (P ≤ 0.01) serum BUN and insulin sensitivity (calculated using RQUICKI) compared to Calm steers. During the GTT, Temperamental steers had greater (P < 0.01) serum glucose, yet decreased (P = 0.03) serum insulin, and (P < 0.01) serum insulin: serum glucose compared to Calm cattle. During the IST, Temperamental steers had greater (P < 0.01) serum insulin and a greater (P < 0.01) serum insulin: serum glucose as compared to Calm steers. These data demonstrate that differences exist in the manner in which Temperamental steers respond to glucose and insulin, potentially a result of elevated serum NEFA concentrations, which may result in changes in utilization and redistribution of energy in Temperamental versus Calm cattle.

      PubDate: 2016-03-05T16:53:21Z
  • Molecular characterization of kisspeptin gene and effect of
           nanoencapsulted kisspeptin-10 on reproductive maturation in Catla catla
    • Abstract: Publication date: Available online 3 March 2016
      Source:Domestic Animal Endocrinology
      Author(s): M.A. Rather, I.A. Bhat, G.B. Pathakota, A. Chaudhari, J.K. Sundaray, R. Sharma
      Kisspeptin, a member of the RF-amide related peptide family, has emerged recently as an essential gatekeeper of various reproductive processes via its ability to activate kisspeptin receptors at puberty. In this study, the kiss1 gene and its receptor kiss1rb were cloned and characterized from the brain of Catla catla. Further, the effects of kissppetin-10 (K-10) and chitosan encapsulated K-10 nanoparticles (CK-10) on gene expression were assessed. The full-length cDNA sequence of kiss1 is 754 bp with an open reading frame (ORF) of 351 bp that encodes a putative protein of 116 amino acids. The kiss1rb cDNA is 1280 bp long and contains a 5'-UTR (untranslated region) of 30 bp, 3'-UTR of 149 bp, and an ORF(open reading frame) of 1101 bp. The expression patterns of kiss1 and kiss1rb mRNA in basal tissues revealed that they are mainly expressed in the brain, pituitary gland and gonads. CK-10 nanoparticles with a particle size of 125 nm and a zeta potential of 36.45 mV were synthesized and compared with K-10. Chitosan nanoparticles showed 60% entrapment efficiency for K-10. The mRNA expression of reproductive genes (GnRH, LH and FSH) in fish injected with K-10 declined after 6 h while those injected with CK-10 showed controlled and a sustained surge of mRNA expression of these genes with a peak at 12 h. Histological examination of ovaries indicated a pronounced effect of CK-10 on maturation and gonadal development. The study reports that this sustained-release-delivery-system will help in increasing the half-life of K-10 and other therapeutic protein drugs in the biological system. Besides, the nanoformulation developed in the current study may be useful for developing therapies against various reproductive dysfunctions in vertebrates.

      PubDate: 2016-03-05T16:53:21Z
  • Editorial Board
    • Abstract: Publication date: April 2016
      Source:Domestic Animal Endocrinology, Volume 55

      PubDate: 2016-03-05T16:53:21Z
  • Table of Contents
    • Abstract: Publication date: April 2016
      Source:Domestic Animal Endocrinology, Volume 55

      PubDate: 2016-03-05T16:53:21Z
  • Endocrine, morphometric and ultrasonographic characterization of neck
           adiposity in Andalusian horses
    • Abstract: Publication date: Available online 26 February 2016
      Source:Domestic Animal Endocrinology
      Author(s): T. Martin-Gimenez, I. de Blas, E. Aguilera-Tejero, E. Diez de Castro, C.N. Aguirre-Pascasio
      Equine Metabolic Syndrome (EMS) can be diagnosed by hormonal measurements; however, it would be important to find simpler measurements that allow easy identification of affected or at risk individuals. In horses, the dorsal neck region is one of the most frequent anatomical sites for fat deposition and neck obesity has been linked to EMS. The aim of this study was to evaluate the association of hormonal markers of obesity (leptin) and insulin resistance (insulin) with morphometric and ultrasonographic neck measurements in Andalusian horses. Plasma leptin and insulin concentrations were measured by radioimmunoassay in 127 Andalusian horses. Neck circumferences (NC) were measured at three equidistant locations at 25%, 50% and 75% of neck length (NC-25%, NC-50%, NC-75%). At the same three locations, subcutaneous fat thickness (SFT-25%, SFT-50%, SFT-75%) was measured ultrasonographically. In the population under study, a tendency to adiposity was confirmed by the elevated plasma leptin levels (7.47 ± 5.03 ng/mL). However, plasma insulin concentrations (4.05 ± 3.74 μIU/mL) were within normal range in most horses. Our results indicate that NC showed significant sexual dimorphism and did not correlate well with hormonal measurements. Ultrasonographic assessment of fat thickness at the base of the neck (SFT-75%) was significantly correlated with both plasma leptin and insulin, and did not show differences between males and females. Thus, in the search for a single objective parameter which can be used in large populations SFT-75% is a potential candidate and may be a meaningful parameter to predict EMS.

      PubDate: 2016-02-29T16:06:26Z
  • Expression of nerve growth factor and its receptors in the uterus of
           rabbits: functional involvement in prostaglandin synthesis
    • Abstract: Publication date: Available online 19 February 2016
      Source:Domestic Animal Endocrinology
      Author(s): M. Maranesi, F. Parillo, L. Leonardi, P.G. Rebollar, B. Alonso, L. Petrucci, A. Gobbetti, C. Boiti, J. Arruda-Alencar, A. Moura, M. Zerani
      The aim of the present study was to evaluate: 1) the presence of nerve growth factor (NGF) and the neurotrophic tyrosine kinase receptor 1 (NTRK1) and nerve growth factor receptor (NGFR) in the rabbit uterus; and 2) the in vitro effects of NGF on PGF2α and PGE2 synthesis and on the PGE2-9-ketoreductase (PGE2-9-K) activity by the rabbit uterus. NGF, NTRK1, and NGFR were immunolocalized in the luminal and glandular epithelium and stroma cells of the endometrium. RT-PCR indicated the presence of mRNA for NGF, NTRK1, and NGFR in the uterus. NGF increased (P < 0.01) in vitro secretions of PGF2α and PGE2 but co-incubation with either NTRK1 or oxide nitric synthase (NOS) inhibitors reduced (P < 0.01) PGF2α production and blocked (P < 0.01) PGE2 secretion. Prostaglandins releases were lower (P < 0.01) than control when uterine samples were treated with NGF plus cyclooxygenase (COX) inhibitor. However, addition of NGFR inhibitor reduced (P < 0.01) PGF2α secretion less efficiently than NTRK1 or NOS inhibitors, but had no effect on PGE2 yield. NGF increased (P < 0.01) the activity of PGE2-9-K, while co-incubation with NTRK1 or NOS inhibitors abolished (P < 0.01) this increase in PGE2-9-K activity. However, co-treatment with either COX or NGFR inhibitors had no effect on PGE2-9-K activity. This is the first study to document the distribution of NGF/NTRK1 and NGFR systems and their effects on PG synthesis in the rabbit uterus. NGF/NTRK1 increases PGF2α and PGE2 productions by up-regulating NOS and PGE2-9-K activities, whereas NGF/NGFR augments only PGF2α secretion, through an intracellular mechanism that is still unknown.

      PubDate: 2016-02-20T13:06:37Z
  • Increased expression of pentraxin 3 after in vivo and in vitro stimulation
           with gonadotropins in porcine oocyte-cumulus complexes and granulosa cells
    • Abstract: Publication date: Available online 19 February 2016
      Source:Domestic Animal Endocrinology
      Author(s): E. Nagyova, J. Kalous, L. Nemcova
      It has been previously shown that multimeric pentraxin 3 (PTX3) is a key component of the cumulus oophorus extracellular matrix (ECM) in mice. In response to the ovulatory LH surge, the cumulus cells assemble a unique ECM that envelopes the oocyte and cumulus cell complex. Importantly, cumuli from PTX3-/- mice were defective in their ECM organization and their fertility was impaired. It has been demonstrated that tumor necrosis factor alpha-induced protein 6 (TNFAIP6) catalyzes the formation of heavy chains of (inter-alpha-trypsin inhibitor) -hyaluronan complexes and these are then cross-linked via PTX3. This process is tightly regulated, and requires the proteins to meet/interact in the correct order. Finally, in this way the above-listed proteins form the cumulus oophorus ECM. We investigated whether PTX3 is expressed in the porcine preovulatory follicle. Porcine oocyte-cumulus complexes (OCC) and mural granulosa cells (MGC) from gilts were obtained either after stimulation in vivo with eCG/ hCG (4, 8, 16, 24 and 32 h) or culture in vitro (4, 24 and 44 h) in FSH/LH-supplemented medium. The methods performed were real-time RT-PCR, Western blot analysis, and immunostaining. The expression of PTX3 transcripts was significantly increased 24 h after either in vivo hCG stimulation or in vitro FSH/LH treatment in both OCC and MGC. Western blot analysis with PTX3 antibody revealed that not only matrix extracts from in vivo stimulated gilts contain high levels of PTX3 protein, but also matrix extracts of FSH/LH-stimulated OCC cultured in medium supplemented either with follicular fluid or with porcine serum. The localization of PTX3 in the cumulus oocyte complex was confirmed by immunostaining. In conclusion, PTX3 is produced by porcine OCC and mural granulosa cells both in vivo and in vitro with gonadotropin stimuli inducing cumulus expansion.

      PubDate: 2016-02-20T13:06:37Z
  • Expression analysis of bone morphogenetic protein 4 between fat and lean
           birds in adipose tissue and serum
    • Abstract: Publication date: Available online 30 January 2016
      Source:Domestic Animal Endocrinology
      Author(s): B.H. Cheng, L. Leng, M.Q. Wu, Q. Zhang, X.Y. Zhang, S.S. Xu, Z.P. Cao, Y.M. Li, P. Luan, H. Li
      The objectives of the current study were to characterize the tissue expression of chicken (Gallus gallus) bone morphogenetic protein 4 (BMP4) and compare differences in its expression in abdominal fat tissue and serum between fat and lean birds, and to determine a potential relationship between the expression of BMP4 and abdominal fat tissue growth and development. The results showed that chicken BMP4 mRNA and protein were expressed in various tissues, and the expression level of BMP4 transcript and protein was relatively higher in adipose tissues. In addition, the mRNA and protein expression levels of BMP4 in abdominal fat tissue of fat males were lower than that of lean males at 1, 2, 5 and 7 wk of age (P < 0.05). Furthermore, the serum BMP4 content of fat males was lower than that of lean males at 7 wk of age (P < 0.05). Bone morphogenetic protein 4 mRNA expression levels were significantly higher in preadipocytes than in mature adipocytes (P < 0.05), and the expression level decreased during differentiation in vitro (P < 0.05). These results suggested that chicken BMP4 might affect abdominal fat deposition through differences in its expression level. The results of this study will provide basic molecular information for studying the role of BMP4 in the regulation of adipogenesis in avian species.

      PubDate: 2016-02-01T12:11:52Z
  • Effects of steroid treatment on growth, nutrient partitioning, and
           expression of genes related to growth and nutrient metabolism in adult
           triploid rainbow trout (Oncorhynchus mykiss)
    • Abstract: Publication date: Available online 25 January 2016
      Source:Domestic Animal Endocrinology
      Author(s): B.M. Cleveland, G.M. Weber
      The contribution of sex steroids to nutrient partitioning and energy balance during gonad development was studied in rainbow trout. Specifically, 19-mo old triploid (3N) female rainbow trout were fed treatment diets supplemented with estradiol-17β (E2), testosterone (T), or dihydrotestosterone (DHT) at 30 mg steroid/kg diet for a 1-mo period. Growth performance, nutrient partitioning, and expression of genes central to growth and nutrient metabolism were compared to 3N and age-matched diploid (2N) female fish consuming a control diet not supplemented with steroids. Only 2N fish exhibited active gonad development, with gonad weights (GSI) increasing from 3.7% to 5.5% of body weight throughout the study while GSI in 3N fish remained at 0.03%. Triploid fish consuming DHT exhibited faster specific growth rates than 3N controls (P < 0.05). Consumption of E2 in 3N fish reduced fillet growth and caused lower fillet yield compared to all other treatment groups (P < 0.05). In contrast, viscera fat gain was not affected by steroid consumption (P > 0.05). Gene transcripts associated with physiological pathways were identified in maturing 2N and E2-treated 3N fish that differed in abundance from 3N control fish (P < 0.05). In liver these mechanisms included the growth hormone/insulin-like growth factor (IGF) axis (igf1, igf2), IGF binding proteins (igfbp1b1, igfbp2b1, igfbp5b1, igfbp6b1), and genes associated with lipid binding and transport (fabp3, fabp4, lpl, cd36), fatty acid oxidation (cpt1a), and the pparg transcription factor. In muscle these mechanisms included reductions in myogenic gene expression (fst, myog) and the proteolysis-related gene, ctsl, suggesting an E2-induced reduction in the capacity for muscle growth. These findings suggest that increased E2 signaling in the sexually maturing female rainbow trout alters physiological pathways in liver, particularly those related to IGF signaling and lipid metabolism, to partition nutrients away from muscle growth towards support of maturation-related processes. In contrast, the mobilization of viscera lipid stores appear to be mediated less by E2 and more by energy demands associated with gonad development. These findings improve understanding of how steroids regulate nutrient metabolism to meet the high energy demands associated with gonad development during sexual maturation.

      PubDate: 2016-01-28T12:02:36Z
  • Leptin concentrations in finishing beef steers and heifers and their
           association with dry matter intake, average daily gain, feed efficiency,
           and body composition
    • Abstract: Publication date: Available online 6 January 2016
      Source:Domestic Animal Endocrinology
      Author(s): A.P. Foote, R.G. Tait, D.H. Keisler, K.E. Hales, H.C. Freetly
      The objective of this experiment was to determine the association of circulating plasma leptin concentrations with production and body composition measures of finishing beef steers and heifers and to determine if multiple sampling time points improve the associations of plasma leptin concentrations with production and body composition traits. Individual DMI and ADG were determined for 84 d using steers and heifers (n = 127 steers and n = 109 heifers). Blood was collected on day 0, day 42, and day 83 for determination of plasma leptin concentrations. Leptin concentrations was greater in heifers than steers on day 0 (P < 0.001 for sex by day interaction) and leptin concentrations increased in both sexes but was not different from each other on day 83. Leptin concentrations at all three time points and the mean were shown to be positively associated with DMI (P ≤ 0.006) while the mean leptin concentration explaining 8.3 % of the variance of DMI. Concentrations of leptin at day 42, day 83, and the mean of all three time points were positively associated with ADG (P ≤ 0.011). Mean leptin concentration was negatively associated with G:F and positively associated with residual feed intake (RFI), indicating that more efficient cattle had lower leptin concentrations. However, leptin concentrations explained very little of the variation in RFI (≤ 3.2 % of the variance). Leptin concentrations were positively associated with body fat measured by ultrasonography at the 12th-rib and over the rump (P < 0.001), with the mean leptin concentration explaining 21.9 % and 12.7 % of the variance in 12th rib and rump fat thickness, respectively. The same trend was observed with carcass composition where leptin concentrations were positively associated with 12th rib fat thickness, USDA calculated yield grade (YG), and marbling score (P ≤ 0.006) and mean leptin concentration explained 16.8, 18.2, and 4.6 % of the variance for 12th rib fat thickness, YG, and marbling score, respectively. Given these and previous results, it appears that leptin physiology could be a candidate for mechanisms that contribute to feed intake and feed efficiency variation in beef cattle.

      PubDate: 2016-01-09T09:23:37Z
  • Ovarian follicle development in vitro and oocyte competence: advances and
           challenges for farm animals
    • Abstract: Publication date: Available online 7 January 2016
      Source:Domestic Animal Endocrinology
      Author(s): J.R.V. Silva, R. van den Hurk, J.R. Figueiredo
      During the last two decades, research on in vitro preantral follicle growth and oocyte maturation has delivered fascinating advances concerning the knowledge of processes regulating follicle growth and the developmental competence of oocytes. These advances include: (1) information about the role of several hormones and growth factors on in vitro activation of primordial follicles; (2) increased understanding of the intracellular pathway involved in the initiation of primordial follicle growth, (3) the growth of primary and secondary follicles up to antral stages, and (4) production of embryos from oocytes from in vitro grown preantral follicles. This review paper describes these advances, especially in regard farm animals, and discusses the reasons that limit embryo production from oocytes derived from preantral follicles cultured in vitro.

      PubDate: 2016-01-09T09:23:37Z
  • Plasma concentrations of acyl-ghrelin are associated with average daily
           gain and feeding behavior in grow-finish pigs1
    • Abstract: Publication date: Available online 4 January 2016
      Source:Domestic Animal Endocrinology
      Author(s): C.A. Lents, T.M. Brown-Brandl, G.A. Rohrer, W.T. Oliver, B.A. Freking
      The objectives of this study were to determine the effect of sex, sire line, and litter size on concentrations of acyl-ghrelin and total ghrelin in plasma of grow-finish pigs, and to understand the relationship of plasma concentrations of ghrelin with feeding behavior, average daily gain (ADG), and back fat (BF) in grow-finish swine. Yorkshire-Landrace crossbred dams were inseminated with semen from Yorkshire, Landrace, or Duroc sires. Within 24 h of birth, pigs were cross-fostered into litter sizes of normal (N; > 12 pigs/litter) or small (S; ≤ 9 pigs/litter). At 8 wk of age, pigs (n = 240) were blocked by sire breed, sex, and litter size and assigned to pens (n = 6) containing commercial feeders modified with a system to monitor feeding behavior. Total time eating, number of daily meals, and duration of meals were recorded for each individual pig. Body weight (BW) was recorded every 4 wk. Back fat and loin eye area (LEA) were recorded at the conclusion of the 12-wk feeding study. A blood sample was collected at week 7 of the study to quantify concentrations of acyl- and total ghrelin in plasma. Pigs from S litters weighed more (P < 0.05) and tended (P = 0.07) to be fatter than pigs from N litters. Postnatal litter size did not affect ADG, feeding behavior, or concentrations of ghrelin in plasma during the grow-finish phase. Barrows spent more time eating (P < 0.001) than gilts but the number of meals and concentrations of ghrelin did not differ with sex of the pig. Pigs from Duroc and Yorkshire sires had lesser (P < 0.0001) concentrations of acyl-ghrelin than pigs from Landrace sires, but plasma concentrations of total ghrelin were not affected by sire breed. Concentrations of acyl-ghrelin were positively correlated with the number of meals and negatively correlated with meal length and ADG (P < 0.05). A larger number of short-duration meals may indicate that pigs with greater concentrations of acyl-ghrelin consumed less total feed, which likely explains why they were leaner and grew more slowly. Acyl-ghrelin is involved in regulating feeding behavior in pigs, and measuring acyl-ghrelin is important when trying to understand the role of this hormone in swine physiology.

      PubDate: 2016-01-05T08:15:32Z
  • Concentrations of progesterone, a metabolite of PGF2α, prolactin, and
           LH during development of idiopathic persistent corpus luteum in mares
    • Abstract: Publication date: Available online 28 December 2015
      Source:Domestic Animal Endocrinology
      Author(s): O.J. Ginther, J.M. Baldrighi, T. Castro, C.A. Wolf, V.G. Santos
      In experiment 1, daily blood samples were available from Days 0 to 20 (Day 0 = ovulation) in mares with an interovulatory interval (IOI, n=5) and in mares that developed idiopathic persistent corpus luteum (PCL, n=5). The PCL was confirmed by maintenance of progesterone (P4) concentration until end of the experiment (Day 20). Significant interactions of group and day revealed the novel findings that LH was lower (P < 0.05) in the PCL group than in the IOI group on Days 0 to 4, and prolactin was lower (P < 0.05) on Days 1, 4, 6, and 7. In experiment 2, treatment with a GnRH antagonist (n=6) significantly reduced LH on Days 1 to 6 compared to the controls (n=6) but did not support the hypothesis that low LH during the postovulatory period increases the frequency of PCL. In experiment 3, P4, PGFM (a PGF2α metabolite), and prolactin concentrations on Days 12 to 20 from 2 reported experiments were combined to increase the number of mares with an IOI (n=11) or a PCL (n=11). An abrupt and complete decrease in P4 (luteolysis) began on Day 13 in the IOI group compared to a gradual and partial P4 decline after Day 12 in the PCL group. Concentrations of PGFM and prolactin were lower (P < 0.05) in the PCL group than in the IOI group on the day at the end of the most pronounced decrease in P4. The PCL mares were subgrouped into those with an abrupt but incomplete P4 decrease (partial luteolysis; n=5) at the expected time and those without partial luteolysis (n=6). There were no significant differences between the 2 subgroups in concentrations of PGFM and prolactin, but on a tentative basis (P < 0.10) concentration of PGFM seemed more focused on the day of the most pronounced decrease in P4 in the subgroup with partial luteolysis. Results for PCL compared to IOI indicated: (1) postovulatory LH and prolactin were lower, (2) treatment to reduce postovulatory LH did not increase the incidence, and (3) both PGFM and prolactin were lower on the day of the most pronounced decrease in P4.

      PubDate: 2016-01-01T04:42:24Z
  • Aquaporin 3 is regulated by estrogen in the chicken oviduct and it is
           involved in progression of epithelial cell-derived ovarian carcinomas
    • Abstract: Publication date: Available online 23 December 2015
      Source:Domestic Animal Endocrinology
      Author(s): C. Yang, W. Lim, H. Bae, G. Song
      Aquaporins (AQPs) are membrane proteins that passively deliver water across the plasma membrane to play an important role in maintaining cell shape. Members of the AQP family are distributed in the majority of tissues in the human body and perform a variety of functions based on the water homeostasis suitable for each organ. However, there is little known about expression and regulation of AQP family members in chickens. Therefore, we determined the expression of AQPs in various tissues of chickens. Among 13 isotypes, AQP3 was highly expressed in the chicken oviduct. Expression of AQP3 mRNA increased in the magnum (P < 0.001) and isthmus (P < 0.001) of chick oviducts treated with diethylstilbestrol (DES). Consistent with these results the localization of AQP3 was detected in the glandular (GE) and luminal (LE) epithelia of the magnum and isthmus of oviducts of DES-treated chicks. In addition, the pattern of expression of AQP3 changed in an estrogen-dependent manner during the molting period. During the regenerative period of the oviduct after molting, expression of AQP3 mRNA increased coordinately with increaseing concentrations of estradiol (P < 0.001), whereas expression of AQP3 mRNA decreased as concentrations of estradiol in plasma decreased in response to induced molting (P < 0.001). Also, expression of the AQP3 increased (P<0.001) in cancerous ovaries of laying hens. In conclusion, AQP3 does not simply function to transport water into and out of cells, but also appears to be closely involved in development of the chicken oviduct which is regulated by estrogens. Furthermore, our results suggest AQP3 as a new diagnostic for early detection and treatment of epithelial cell-derived ovarian carcinomas.

      PubDate: 2015-12-24T02:57:40Z
  • Expression and immunolocalization of membrane progesterone receptors in
           the bovine oviduct
    • Abstract: Publication date: Available online 17 December 2015
      Source:Domestic Animal Endocrinology
      Author(s): M.K. Kowalik, M. Martyniak, R. Rekawiecki, J. Kotwica
      The oviduct plays a crucial role in the transport and maturation of gametes and ensures suitable conditions for fertility and early embryo development. One regulator of oviduct function is progesterone (P4), which affects the cell by interacting with nuclear progesterone receptors (PGR) as well as through non-genomic mechanisms, presumably involving membrane progesterone receptors. The aim of this study was to evaluate expression of mRNAs and proteins for progesterone receptor membrane component (PGRMC) 1 and 2 and membrane progestin receptors (mPR) α, β and γ and to use immunohistochemistry to demonstrate their cell-specific localization in the bovine oviduct. Oviducts ipsilateral and contralateral to the CL or to the dominant follicle were collected from cows on days 6-12 (mid-luteal stage) and 18-20 (follicular stage) of the estrous cycle and divided into three parts (infundibulum, ampulla and isthmus). There were no differences (P>0.05) in the PGRMC1, PGRMC2, mPRα, β and γ mRNA expression between ipsi- and contralateral oviducts. However, the same parts of the oviduct collected during the different stages of the estrous cycle showed higher (P<0.05) mRNA levels of PGRMC1, PGRMC2 and mPRα on days 18-20 than on days 6-12 of the estrous cycle. mPRα and mPRβ mRNA levels were higher (P<0.05) in the infundibulum than in the isthmus, while PGRMC1 expression was higher (P<0.05) in the infundibulum than in ampulla. Immunohistochemistry was used to detect PGRMC1, PGRMC2, PRα, β and γ proteins in all parts of both oviducts from days 6-12 and 18-20 of the estrous cycle. There were no differences in the staining intensity and cellular localization of the studied proteins between the ipsi- and contralateral oviducts and between the studied stages of the estrous cycle. A strong positive reaction was observed in luminal cells, but this reaction was less evident in myocytes and stromal cells. All proteins were also localized to the endothelial cells of blood vessels. These results suggest that membrane P4 receptors, may be involved in the regulation of oviduct motility, secretory function and blood flow in this organ.

      PubDate: 2015-12-20T02:50:22Z
  • Endogenous and exogenous factors influencing the concentrations of
           adiponectin in body fluids and tissues in the bovine
    • Abstract: Publication date: Available online 13 December 2015
      Source:Domestic Animal Endocrinology
      Author(s): Helga Sauerwein, Susanne Häußler
      Adiponectin, one of the messenger molecules secreted from adipose tissue that are collectively termed adipokines, has been demonstrated to play a central role in lipid and glucose metabolism in humans and laboratory rodents; it improves insulin sensitivity and exerts anti-diabetic and anti-inflammatory actions. Adiponectin is synthesized as a 28 kDa monomer but is not secreted as such; instead it is glycosylated and undergoes multimerization to form different molecular weight (MW) multimers prior to secretion. Adiponectin is one of the most abundant adipokines (μg/mL range) in the circulation. The concentrations are negatively correlated with adipose depot size, in particular with visceral fat mass in humans. Adiponectin exerts its effects by activating a range of different signaling molecules via binding to two transmembrane receptors, AdipoR1 and AdipoR2. The AdipoR1 is expressed primarily in the skeletal muscle, whereas AdipoR2 is predominantly expressed in the liver. Many of the functions of adiponectin are relevant to growth, lactation and health and are thus of interest in both beef and dairy production systems. Studies on the role of the adiponectin protein in cattle have been impeded by the lack of reliable assays for bovine adiponectin. While there are species specific bovine adiponectin assays commercially available, they suffer from a lack of scientific peer-review of validity. Quantitative data about the adiponectin protein in cattle available in the literature emerged only during the last three years and were largely based on Western blotting using either antibodies against human adiponectin or partial peptides from the bovine sequence. Using native bovine high MW adiponectin purified from serum, we were able to generate a polyclonal antiserum that can be used for Western Blot but also in an ELISA system which was recently validated. The objective of this review is to provide an overview of the literature about the adiponectin protein in cattle addressing the following aspects: (a) the course of the adiponectin serum concentrations during development in both sexes, during inflammation, nutritional energy deficit and energy surplus, and lactation-induced changes including the response to supplementation with conjugated linoleic acids and with niacin, (b) the concentrations of adiponectin in subcutaneous versus visceral fat depots of dairy cows, (c) the protein expression of adiponectin in tissues other than adipose and (d) the concentrations in different body fluids including milk.

      PubDate: 2015-12-16T02:41:26Z
  • Editorial Board
    • Abstract: Publication date: January 2016
      Source:Domestic Animal Endocrinology, Volume 54

      PubDate: 2015-12-12T02:30:57Z
  • Table of Contents
    • Abstract: Publication date: January 2016
      Source:Domestic Animal Endocrinology, Volume 54

      PubDate: 2015-12-12T02:30:57Z
  • Changes in brain ribonuclease (BRB) messenger RNA in granulosa cells (GCs)
           of dominant vs subordinate ovarian follicles of cattle and the regulation
           of BRB gene expression in bovine GCs
    • Abstract: Publication date: Available online 31 October 2015
      Source:Domestic Animal Endocrinology
      Author(s): J.L. Dentis, N.B. Schreiber, J.N. Gilliam, L.F. Schutz, L.J. Spicer
      Brain ribonuclease (BRB) is a member of the ribonuclease A superfamily that is constitutively expressed in a range of tissues and is the functional homolog of human ribonuclease 1. This study was designed to characterize BRB gene expression in granulosa cells (GCs) during development of bovine dominant ovarian follicles and to determine the hormonal regulation of BRB in GCs. Estrous cycles of Holstein cows (n = 18) were synchronized, and cows were ovariectomized on either day 3 to 4 or day 5 to 6 after ovulation during dominant follicle growth and selection. Ovaries were collected, follicular fluid (FFL) was aspirated, and GCs were collected for RNA isolation and quantitative polymerase chain reaction. Follicles were categorized as small (1–5 mm; pooled per ovary), medium (5–8 mm; individually collected), or large (8.1–17 mm; individually collected) based on surface diameter. Estradiol (E2) and progesterone (P4) levels were measured by radioimmunoassay (RIA) in FFL. Abundance of BRB messenger RNA (mRNA) in GCs was 8.6- to 11.8-fold greater (P < 0.05) in small (n = 31), medium (n = 66), and large (n = 33) subordinate E2-inactive (FFL E2 < P4) follicles than in large (n = 16) dominant E2-active (FFL E2 > P4) follicles. In the largest 4 follicles, GCs BRB mRNA abundance was negatively correlated (P < 0.01) with FFL E2 (r = −0.65) and E2:P4 ratio (r = −0.46). In experiment 2, GCs from large (8–22 mm diameter) and small (1–5 mm diameter) follicles were treated with insulin-like growth factor 1 (IGF1; 0 or 30 ng/mL) and/or tumor necrosis factor alpha (0 or 30 ng/mL); IGF1 increased (P < 0.05) BRB mRNA abundance, and tumor necrosis factor alpha decreased (P < 0.001) the IGF1-induced BRB mRNA abundance in large-follicle GCs. In experiment 3 to 6, E2, FSH, fibroblast growth factor 9, cortisol, wingless 3A, or sonic hedgehog did not affect (P > 0.10) abundance of BRB mRNA in GCs; thyroxine and LH increased (P < 0.05), whereas prostaglandin E2 (PGE2) decreased (P < 0.05) BRB mRNA abundance in small-follicle GCs. Treatment of small-follicle GCs with recombinant human RNase1 increased (P < 0.05) GCs numbers and E2 production. In conclusion, BRB is a hormonally and developmentally regulated gene in bovine GCs and may regulate E2 production during follicular growth in cattle.

      PubDate: 2015-12-04T02:12:55Z
  • Follicle-stimulating hormone–induced rescue of cumulus cell
           apoptosis and enhanced development ability of buffalo oocytes
    • Abstract: Publication date: Available online 31 October 2015
      Source:Domestic Animal Endocrinology
      Author(s): A. Jain, T. Jain, P. Kumar, M. Kumar, S. De, M. Gohain, R. Kumar, T.K. Datta
      The effect of follicle-stimulating hormone (FSH) on apoptotic status of cumulus cells, expression of proapoptotic and antiapoptotic genes, and development rate of in vitro fertilization–produced buffalo embryos were investigated. FSH supplementation in in vitro maturation–medium resulted in a dose-dependent reduction in the expression of proapoptotic genes namely, BCL2-associated X protein (BAX), cytochrome c, and caspase-3 and increase in the expression of antiapoptotic genes such as B-cell lymphoma 2 (BCL2) and X-linked inhibitor of apoptosis protein (XIAP) in cumulus cells of mature oocyte. Cumulus expansion, oocyte maturation, cleavage, and blastocyst development rates were significantly higher (P < 0.05) in 5 and 10-μg/mL FSH-supplemented groups as compared with control. Significant increase in the expression of FSH receptor messenger RNA was also found with 5 and 10-μg/mL FSH (P < 0.05). TUNEL assay confirmed that the population of apoptotic cumulus cells of matured oocytes was reduced in the FSH-treated groups as compared with control (P < 0.05). In conclusion, our data suggest that FSH may attenuate apoptosis in cumulus cells via mitochondria-dependent apoptotic pathway by increasing XIAP expression, resulting in a more favorable ratio of BCL2/BAX expression and decreasing the cytochrome c and caspase-3 expression, eventually contributing to developmental competence of oocytes. The information generated will help in improving the in vitro embryo production program in buffalo.

      PubDate: 2015-12-04T02:12:55Z
  • Prolonged hyperinsulinemia affects metabolic signal transduction markers
           in a tissue specific manner
    • Abstract: Publication date: Available online 19 November 2015
      Source:Domestic Animal Endocrinology
      Author(s): A. Campolo, M.A. de Laat, L. Keith, K.J. Gruntmeir, V.A. Lacombe
      Insulin dysregulation is common in horses although the mechanisms of metabolic dysfunction are poorly understood. We hypothesized that insulin signaling in striated (cardiac and skeletal) muscle and lamellae may be mediated through different receptors as a result of receptor content, and that transcriptional regulation of downstream signal transduction and glucose transport may also differ between tissues sites during hyperinsulinemia. Archived samples from horses treated with a prolonged insulin infusion or a balanced electrolyte solution were used. All treated horses developed marked hyperinsulinemia and clinical laminitis. Protein expression was compared across tissues for the insulin receptor and insulin-like growth factor 1 receptor (IGF-1R) by immunoblotting. Gene expression of metabolic insulin-signaling markers (insulin receptor substrate 1, Akt2, and glycogen synthase kinase 3 beta [GSK-3β]) and glucose transport (basal glucose transporter 1 and insulin-sensitive glucose transporter 4) was evaluated using real-time reverse transcription polymerase chain reaction. Lamellar tissue contained significantly more IGF-1R protein than skeletal muscle, indicating the potential significance of IGF-1R signaling for this tissue. Gene expression of the selected markers of insulin signaling and glucose transport in skeletal muscle and lamellar tissues was unaffected by prolonged hyperinsulinemia. In contrast, the significant upregulation of Akt2, GSK-3β, GLUT1, and GLUT4 gene expression in cardiac tissue suggested that the prolonged hyperinsulinemia induced an increase in insulin sensitivity and a transcriptional activation of glucose transport. Responses to insulin are tissue-specific, and extrapolation of data across tissue sites is inappropriate.

      PubDate: 2015-12-04T02:12:55Z
  • Dietary melatonin alters uterine artery hemodynamics in pregnant Holstein
    • Abstract: Publication date: January 2016
      Source:Domestic Animal Endocrinology, Volume 55
      Author(s): K.E. Brockus, C.G. Hart, C.L. Gilfeather, B.O. Fleming, C.O. Lemley
      The objective was to examine uterine artery hemodynamics and maternal serum profiles in pregnant heifers supplemented with dietary melatonin (MEL) or no supplementation (CON). In addition, melatonin receptor–mediated responses in steroid metabolism were examined using a bovine endometrial epithelial culture system. Twenty singleton pregnant Holstein heifers were supplemented with 20 mg of melatonin (n = 10) or no melatonin supplementation (control; n = 10) from days 190 to 262 of gestation. Maternal measurements were recorded on days 180 (baseline), 210, 240, and 262 of gestation. Total uterine blood flow was increased by 25% in the MEL-treated heifers compared with the CON. Concentrations of progesterone were decreased in MEL vs CON heifers. Total serum antioxidant capacity was increased by 43% in MEL-treated heifers when compared with CON. Activity of cytochrome P450 1A, 2C, and superoxide dismutase was increased in bovine endometrial epithelial cells treated with melatonin, whereas the melatonin receptor antagonist, luzindole, negated the increase in cytochrome P450 2C activity. Moreover, estradiol or progesterone treatment altered bovine uterine melatonin receptor expression, which could potentiate the melatonin-mediated responses during late gestation. The observed increase in total uterine blood flow during melatonin supplementation could be related to its antioxidant properties. Compromised pregnancies are typically accompanied by increased oxidative stress; therefore, melatonin could serve as a therapeutic supplementation strategy. This could lead to further fetal programming implications in conjunction with offspring growth and development postnatally.

      PubDate: 2015-12-04T02:12:55Z
  • Myostatin inhibits porcine intramuscular preadipocyte differentiation
           in vitro
    • Abstract: Publication date: January 2016
      Source:Domestic Animal Endocrinology, Volume 55
      Author(s): W.X. Sun, M.V. Dodson, Z.H. Jiang, S.G. Yu, W.W. Chu, J. Chen
      This study assessed the effect of myostatin on adipogenesis by porcine intramuscular preadipocytes. Intramuscular preadipocytes were isolated from the longissimus dorsi muscle of newborn pigs. Myostatin inhibited intramuscular preadipocyte differentiation in a dose-dependent manner. Myostatin treatment during preadipocyte differentiation significantly (P < 0.05) inhibited the expression of the adipogenic marker genes CCAAT/enhancer-binding protein β, CCAAT/enhancer-binding protein α, peroxisome proliferator-activated receptor γ, sterol regulatory element–binding protein-1c, fatty acid–binding protein, and adiponectin. Myostatin also significantly (P < 0.05) reduced the release of glycerol and decreased both adipose triglyceride lipase and hormone-sensitive lipase expression in intramuscular adipocytes. Our study suggests that myostatin acts as an extrinsic regulatory factor in regulating intramuscular adipogenesis.

      PubDate: 2015-12-04T02:12:55Z
  • The Hypothalamo-pituitary adrenal (HPA) axis in sheep is attenuated during
           lactation in response to psychosocial and predator stress
    • Abstract: Publication date: Available online 23 November 2015
      Source:Domestic Animal Endocrinology
      Author(s): C.R. Ralph, A.J. Tilbrook
      Activation of the hypothalamo-pituitary adrenal (HPA) axis by psychosocial stress is attenuated during lactation. We tested the hypothesis that lactating ewes will have attenuated HPA axis responses to isolation and restraint but will have greater responses to predator stress in the form of barking dogs. We imposed two 4 h stressors: psychosocial stress (isolation and restraint of ewes) and predator stress (barking dogs). Blood was collected i.v. every 10 min from non-lactating ewes (n = 6), lactating ewes with lambs present but not able to be suckled (n = 6) and lactating ewes with lambs present and able to be suckled (n = 6). Plasma cortisol and oxytocin were measured. For non-lactating ewes cortisol increased (P < 0.01) in response to both stressors and these increases were greater (P < 0.01) than in the lactating animals. For lactating ewes with lambs present but unable to be suckled cortisol increased (P < 0.05) in response to both stressors with a greater response to barking dogs (P < 0.05). For lactating ewes with lambs present and able to be suckled, cortisol increased (P < 0.01) in response to barking dogs only. Plasma oxytocin was greater (P < 0.01) in lactating ewes than in non-lactating ewes and did not change in response to the stressors. In conclusion, lactating ewes are likely to have a greater HPA axis response to a stressor that may be perceived to threaten the welfare of themselves and/or their offspring. The role of oxytocin in attenuation of the HPA axis to stress in sheep is unclear from the current research and requires further investigation.

      PubDate: 2015-12-04T02:12:55Z
  • Systemic effect of FSH and intraovarian effect of the corpus luteum on
           complete regression versus recovery of regressing wave-2 follicles in
    • Abstract: Publication date: Available online 26 November 2015
      Source:Domestic Animal Endocrinology
      Author(s): O.J. Ginther, M.A.R. Siddiqui, J.M. Baldrighi, C.A. Wolf
      Each subordinate of the second follicular wave (wave 2) was monitored, and the outcome was classified as fully regressed (decreased in diameter to 2 mm) or recovered (decreased initially and then increased to become a growing follicle of the subsequent wave 1). The changing diameter of each follicle after emergence at 2 mm and plasma concentration of FSH were determined every 12 h from the day of ovulation (Day 0) to 4 d after the subsequent ovulation in heifers with 2 follicular waves per interovulatory interval (n = 10). The number and percentage of wave-2 subordinates that initially regressed and then recovered (7.2 ± 1.0 follicles; 33.2 ± 5.1%) were less (P < 0.0008) than the number and percentage that completely regressed (15.0 ± 1.7; 66.8 ± 5.1%). Follicles that later recovered initially reached maximal diameter on a later day (P < 0.0001) after emergence at 2 mm (4.3 ± 0.2 d) and at a larger (P < 0.0001) diameter (5.8 ± 0.2 mm ) than for follicles that completely regressed (3.2 ± 0.1 d; 4.7 ± 0.1 mm). The FSH surge that stimulated wave 2 began earlier and was more sustained in a subgroup with a high percentage of recovered follicles (61%) than in a subgroup with a low percentage (24%). Recovery began on Day –1.0 ± 0.1 when the follicles had regressed to 3.7 ± 0.1 mm. Diameter of subordinate follicles on Day –6 or before the expected days of luteolysis was greater (P < 0.05) when in the CL ovary than when in the nonCL ovary. During expected luteolysis, more follicles (P < 0.008) per ovary continued to regress when ipsilateral to the CL (9.2 ± 1.1 follicles) than when contralateral (5.8 ± 1.1), and more follicles (P < 0.02) recovered from regression when contralateral to the CL (5.0 ± 0.8) than when ipsilateral (2.2 ± 0.6). The hypothesis that the CL has a local effect on the development, regression, and recovery of the subordinate follicles of wave 2 was supported.

      PubDate: 2015-12-04T02:12:55Z
  • Stimulation of regressing subordinate follicles of wave 2 with a
           gonadotropin product in heifers
    • Abstract: Publication date: Available online 30 November 2015
      Source:Domestic Animal Endocrinology
      Author(s): O.J. Ginther, M.A.R. Siddiqui, J.M. Baldrighi, M.M. Hoffman
      The recovery of regressing wave-2 subordinate follicles was studied by treating heifers with a gonadotropin product that had about 84% and 16% of FSH and LH activity, respectively. A treated group (n = 8) received a single dose of 50 mg (2.5 mL) of the gonadotropin product, and a control group (n = 8) received 2.5 mL of saline vehicle. The group assignment of heifers was not known to the ultrasonographer who tracked the follicles and measured follicle diameters. Follicle measurements began on the day of expected follicle deviation in wave 2 (largest follicle closest to 8.5 mm) and treatment (hour 0) was given on Day 13.4 ± 0.2 (Day 0 = ovulation) when the dominant follicles of waves 1 and 2 were 14.1 ± 0.3 mm and 10.7 ± 0.1 mm, respectively. Subordinate follicles of wave 2 that had regressed to a 3-mm category (3.0 to 3.9 mm) or 4-mm category by hour 0 decreased in diameter for at least 48 h before hour 0, whereas follicles that were in the 5-mm or 6-mm categories at hour 0 did not change significantly in diameter during the previous 48 h. About 55% of the follicles that had regressed to the 3-mm and 4-mm categories at hour 0 and 78% of the follicles in the 5-mm and 6-mm categories increased in diameter after gonadotropin treatment, whereas follicles in the control group continued to decrease (regress) in diameter. The follicles for each of the four diameter categories were greater (P < 0.05) in diameter 9 h after treatment in the treated group than in the control group. The dominant follicle of wave 1 and the largest subordinate follicle of wave 2 in the treated group also increased in diameter so that diameter was greater (P < 0.05) than in the controls at hour 9. The results demonstrated that subordinate follicles of wave 2 that had decreased in diameter (regressed) for at least 48 h retained the capability to recover as indicated by a diameter increase when exposed to a gonadotropin product.

      PubDate: 2015-12-04T02:12:55Z
  • Interleukin 6 increases the in vitro expression of key proteins
           associated with steroidogenesis in the bovine adrenal zona fasciculata
    • Abstract: Publication date: Available online 26 October 2015
      Source:Domestic Animal Endocrinology
      Author(s): S. McIlmoil, J. Strickland, A.M. Judd
      In this study, the in vitro effects of interleukin 6 (IL-6) on the messenger RNAs (mRNAs) and proteins for key steroidogenic factors in the bovine adrenal zona fasciculate (ZF) were determined. Bovine adrenal glands were obtained from an abattoir, and the ZF was isolated. Strips of ZF were then exposed to different concentration of murine IL-6 and/or adrenocorticotropic hormone (ACTH) for various intervals, the protein and mRNA extracted, and the mRNA and protein expression determined by RT-PCR and Western blots. Exposure (1 h) to IL-6 increased in a concentration-dependent manner (10-pg IL-6/mL, P < 0.05 vs control; 100-pg IL-6/mL, P < 0.01 vs control) the relative expression of the mRNAs and proteins for steroidogenic acute regulatory protein (StAR), cholesterol side-chain cleavage enzyme (P450scc), 3β hydroxysteroid dehydrogenase type 2 (3β HSD), 17α-hydroxylase/17,20-lyase/17,20-desmolase (P450 17OH), steroid 21-hydroxylase (P450 21OH), steroid 11-β-hydroxylase type 1 (P450 11βOH), and steroidogenic factor 1 (SF-1), a nuclear factor that increases StAR and steroidogenic enzymes (SEs) expression. Similarly, IL-6 (10 ng/mL) increased the relative expression of proteins and mRNAs for StAR, P450scc, 3β HSD, P450 17OH, P450 21 OH, P450 11βOH, and SF-1 in a time-dependent manner (30 min, P < 0.05 vs control; 60, 120, and 240 min, P < 0.01 vs control). In contrast, IL-6 decreased in a concentration-dependent (P < 0.01 vs control for 1, 10, and 100-ng/mL IL-6) and time-dependent (P < 0.05 vs control for 30, 60,120, and 240 min of 10-ng/mL IL-6) manner the relative expression of the mRNA and protein for adrenal hypoplasia congenita-like protein (DAX-1), a nuclear factor that decreases expression of StAR and SEs. Incubation (1 h) of ZF with 100-nM ACTH increased (P < 0.05 vs control) the relative expression of StAR, P450scc, 3β HSD, P450 17OH, P450 21OH, P450 11βOH, and SF-1 and decreased (P < 0.01 vs control) the relative expression of DAX-1. Murine IL-6 (10 pg/mL) augmented (P < 0.05 vs ACTH) both the stimulatory and inhibitory effects of ACTH. Bovine IL-6 (100 pg/mL, 1-h incubation) also increased (P < 0.01 vs control) the relative expression of the proteins for StAR, P450scc, and SF-1 and decreased (P < 0.01 vs control) the relative expression of DAX-1. In summary, IL-6 increased ZF expression of StAR and 5 SEs, which may be mediated in part by decreasing DAX-1 expression and increasing SF-1 expression.

      PubDate: 2015-12-04T02:12:55Z
  • Defective secretion of PGF2α during development of idiopathic
           persistent corpus luteum in mares
    • Abstract: Publication date: Available online 28 October 2015
      Source:Domestic Animal Endocrinology
      Author(s): O.J. Ginther, T. Castro, J.M. Baldrighi, C.A. Wolf, V.G. Santos
      Five mares that developed idiopathic persistent corpus luteum (PCL) were compared with 5 mares with apparently normal interovulatory intervals (IOIs). Progesterone (P4) and a metabolite of PGF2α (PGFM) were assayed daily beginning on the day of ovulation (Day 0). Transition between the end of an initial progressive P4 increase and the beginning of a gradual decrease in P4 occurred on mean Day 6. The gradual decrease in P4 between Days 6 and 12 was less (approached significance, P < 0.06) in the PCL group than in the IOI group. The P4 concentration on Day 12 (before luteolysis in IOI group) was greater (P < 0.05) in the PCL group than in the IOI group. In a post hoc comparison, an interaction (P < 0.04) of group by day for Days 4 to 7 indicated that the end of the progressive increase in P4 was temporally associated with a transient increase in concentration of PGFM in IOI mares but not in PCL mares. Complete luteolysis (P4 < 1 ng/mL) occurred in the IOI mares on Days 13 to 15. Partial luteolysis (mean P4 decrease, 62%) occurred in 3 of the 5 PCL mares. Normalization to the day at the end of the most pronounced P4 decrease in the IOI mares and in the 3 PCL mares with partial luteolysis resulted in a day-by-group interaction (P < 0.05) for PGFM concentration. The interaction was partly from lower PGFM concentration on the day at the end of the pronounced P4 decrease in the 3 PCL mares than in the IOI mares. The peak of a transient PGFM increase and the day at the end of the most pronounced decrease in P4 were synchronized in each IOI mare but not in any of the 3 PCL mares. In the other 2 PCL mares, partial luteolysis did not occur, and a transient increase in PGFM was not apparent. Results tentatively indicated that the relationship between P4 and PGFM may be altered as early as Day 6 in PCL mares and supported the hypothesis that PGF2α secretion is defective in mares with idiopathic PCL.

      PubDate: 2015-12-04T02:12:55Z
  • Tamoxifen impairs prepubertal mammary development and alters expression of
           estrogen receptor α (ESR1) and progesterone receptors (PGR)
    • Abstract: Publication date: January 2016
      Source:Domestic Animal Endocrinology, Volume 54
      Author(s): H.L.M. Tucker, C.L.M. Parsons, S. Ellis, M.L. Rhoads, R.M. Akers
      Research has shown that prepubertal heifers experience allometric mammary growth that is influenced by the ovaries. Our purpose was to determine the role of estrogen in prepubertal mammary gland development. Sixteen Holstein calves were randomly assigned to 1 of 2 treatment groups: tamoxifen-injected (TAM) or control (CON). Calves were administered the antiestrogen tamoxifen (0.3 mg kg1 d1) or placebo from 28 to 120 d of age. At 120 d, calves were euthanized and udders removed. Weight and DNA content of trimmed parenchymal tissue were halved (P ≤ 0.0001) in TAM compared with CON calves. Parenchymal samples from 3 zones of the left rear mammary gland (lower, middle, and outer regions) were processed for immunohistochemical staining for estrogen receptor α (ESR1) and progesterone receptor (PGR), Ki67-positive cells, and 5-bromo-2'-deoxyuridine label retaining cells (LRCs). Overall, neither the percentage nor location within the epithelial tissue layer of either ESR1- or PGR-positive cells was impacted by TAM treatment. However, image analysis indicated a 6.2-fold lower (P = 0.0001) level of ESR1 protein expression in TAM calves. Similarly, messenger RNA expression of ESR1 was also reduced (P = 0.0001) in TAM heifers. In contrast, expression of PGR protein was greater by 43% (P = 0.03) in TAM calves, but messenger RNA expression did not differ between treatments. Overall, TAM calves had a higher (P ≤ 0.03) percentage and density (cells per tissue area) of Ki67-positive cells. Irrespective of treatment, there were also more Ki67-labeled cells in the outer zones of the mammary gland (P ≤ 0.001). We were able to effectively use multispectral imaging to identify positive cells and quantify the expression of ESR1 and PGR protein. We also identified and counted the proportion of label retaining cells (LCR) (putative epithelial stem cells). We noted an overall 2.9-fold greater number of LRCs in TAM heifers and more LRCs in the outer sampling zones. This suggests that a cohort of LCR cells in TAM remained inactivated in comparison with CON heifers, which exhibited markedly increased growth of the mammary parenchymal tissue over the treatment period. These results suggest that the impacts of ovariectomy are partially explained by loss of ESR1 expression and/or estrogen receptor signaling in the prepubertal bovine mammary gland. The significance of mammary expression of PGR in control of prepubertal bovine mammary development remains unresolved.

      PubDate: 2015-12-04T02:12:55Z
  • Circulating concentrations of glucagon-like peptide 1, glucose-dependent
           insulinotropic peptide, peptide YY, and insulin in client-owned lean,
           overweight, and diabetic cats
    • Abstract: Publication date: January 2016
      Source:Domestic Animal Endocrinology, Volume 54
      Author(s): C.J. McMillan, R.C. Zapata, P.K. Chelikani, E.C.R. Snead, K. Cosford
      Our objectives were to measure plasma concentrations of glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic peptide (GIP), and peptide YY (PYY) in client-owned newly diagnosed diabetic cats and nondiabetic lean or overweight cats and to determine whether circulating concentrations of these hormones differed between study groups and if they increased postprandially as seen in other species. A total of 31 cats were recruited and placed into 1 of 3 study groups: lean (body condition score 4–5 on a scale of 1–9; n = 10), overweight (body condition score 6–8; n = 11), or diabetic (n = 10). Diabetics were newly diagnosed and had not had prior insulin therapy. Preprandial (fasting) and postprandial (60 min after meal) plasma hormone and glucose concentrations were measured at baseline and 2 and 4 wk. All cats were exclusively fed a commercially available high-protein and low-carbohydrate diet commonly prescribed to feline diabetic patients for 2 wk before the 2-wk assessment and continued through the 4-wk assessment. Results showed that plasma concentrations of GLP-1, GIP, PYY, and insulin increased in general after a meal in all study groups. Plasma PYY concentrations did not differ (P > 0.10) between study groups. Diabetics had greater plasma concentrations of GLP-1 and GIP compared with the other study groups at baseline (P < 0.05), and greater preprandial and postprandial GLP-1 concentrations than lean cats at 2 and 4 wk (P < 0.05). Preprandial plasma GIP concentrations were greater in diabetics than obese and lean (P < 0.05) cats at week 4. Postprandial plasma GIP concentrations in diabetics were greater than lean (P < 0.05) at week 2 and obese and lean cats (P < 0.05) at week 4. Together, our findings suggest that diabetic status is an important determinant of circulating concentrations of GLP-1 and GIP, but not PYY, in cats. The role of GLP-1, GIP, and PYY in the pathophysiology of feline obesity and diabetes remains to be determined.

      PubDate: 2015-12-04T02:12:55Z
  • MicroRNA-10b suppresses goat granulosa cell proliferation by targeting
           brain-derived neurotropic factor
    • Abstract: Publication date: January 2016
      Source:Domestic Animal Endocrinology, Volume 54
      Author(s): J.Y. Peng, X.P. An, F. Fang, K.X. Gao, H.Y. Xin, P. Han, L.J. Bao, H.D. Ma, B.Y. Cao
      Brain-derived neurotropic factor (BDNF) and its high-affinity receptor, tyrosine kinase receptor B, have been assumed to be involved in female reproduction and have recently shown to play an essential role in follicle activation and oocyte maturation. In this study, we analyzed the expression of miR-10b and BDNF in the ovary and discovered that the expression of miR-10b was higher in monotocous goat ovaries than in polytocous goat ovaries, whereas the expression pattern of BDNF in ovary was opposite. Moreover, human chorionic gonadotropin induced rapid and transient expression of BDNF messenger RNA and protein. In contrast, human chorionic gonadotropin upregulated miR-10b expression in a time-dependent manner. The BDNF gene was identified as a direct target of miR-10b using a dual-luciferase reporter assay. Transfection of granulosa cells with miR-10b decreased BDNF messenger RNA and protein levels. MiR-10b overexpression inhibited cell proliferation, whereas BDNF promoted cell proliferation. However, a combined treatment with miR-10b and BDNF promoted cell proliferation, indicating that the reintroduction of BDNF reversed the suppressive effect of miR-10b. These results demonstrate that miR-10b downregulates BDNF expression in granulosa cells by directly targeting the 3′ untranslated regions and plays an important role in inhibiting granulosa cell proliferation by targeting BDNF.

      PubDate: 2015-12-04T02:12:55Z
  • Protein and mRNA expression of interleukin 1 system members in bovine
           ovarian follicles and effects of interleukin -1β on primordial
           follicle activation and survival in vitro
    • Abstract: Publication date: Available online 5 October 2015
      Source:Domestic Animal Endocrinology
      Author(s): J.R.S. Passos, J.J.N. Costa, E.V. da Cunha, A.W.B. Silva, R.P. Ribeiro, G.B. de Souza, P.A.A. Barroso, A.M.P. Dau, M.V.A. Saraiva, P.B.D. Gonçalves, R. van den Hurk, J.R.V. Silva
      This study aimed to investigate the expression of interleukin 1 system members (proteins and mRNA of ligands and receptors) and its distribution in ovarian follicles of cyclic cows, as well as to evaluate the effects of interleukin-1β (IL-1β) on the survival and activation of primordial follicles in vitro. The ovaries were processed for localization of interleukin 1 system in preantral and antral follicles by immunohistochemical, real time PCR and western blot analysis. For in-vitro studies, ovarian fragments were cultured in α-MEM+ supplemented with IL-1β (0, 1, 10, 50 or 100 ng/mL), and after 6 days the cultured tissues were processed for histological analysis. Immunohistochemical results showed that the interleukin 1 system proteins IL-1β, IL-1RA, IL-1RI and IL-1RII were detected in the cytoplasm of oocytes and granulosa cells from all follicular categories, and theca cells of antral follicles. Variable levels of mRNA for the interleukin 1 system members were observed at different stages of development. After 6 days of culture, the presence of IL-1β (10 or 50 ng/mL) was effective in maintaining the percentage of normal follicles and in promoting primordial follicle activation. In conclusion, interleukin 1 system members are differentially expressed in ovarian follicles according to their stage of development. Moreover, IL-1β promotes the development of primordial follicles. These results indicate an important role of the interleukin 1 system in the regulation of bovine folliculogenesis.

      PubDate: 2015-10-07T14:01:23Z
  • Studies on lysophosphatidic acid action during in vitro
           preimplantation embryo development
    • Abstract: Publication date: January 2016
      Source:Domestic Animal Endocrinology, Volume 54
      Author(s): D. Boruszewska, E. Sinderewicz, I. Kowalczyk-Zieba, K. Grycmacher, I. Woclawek-Potocka
      Assisted reproductive technologies, including in vitro embryo production (IVP), have been successfully used in animal reproduction to optimize breeding strategies for improved production and health in animal husbandry. Despite the progress in IVP techniques over the years, further improvements in in vitro embryo culture systems are required for the enhancement of oocyte and embryo developmental competence. One of the most important issues associated with IVP procedures is the optimization of the in vitro culture of oocytes and embryos. Studies in different species of animals and in humans have identified important roles for receptor-mediated lysophosphatidic acid (LPA) signaling in multiple aspects of human and animal reproductive tract function. The data on LPA signaling in the ovary and uterus suggest that LPA can directly contribute to embryo–maternal interactions via its influence on early embryo development beginning from the influence of the ovarian environment on the oocyte to the influence of the uterine environment on the preimplantation embryo. This review discusses the current status of LPA as a potential supplement in oocyte maturation, fertilization, and embryo culture media and current views on the potential involvement of the LPA signaling pathway in early embryo development.

      PubDate: 2015-09-25T13:43:18Z
  • Editorial Board
    • Abstract: Publication date: October 2015
      Source:Domestic Animal Endocrinology, Volume 53

      PubDate: 2015-09-25T13:43:18Z
  • Plasma anti-Müllerian hormone as a predictive endocrine marker to
           select Bos taurus (Holstein) and Bos indicus (Nelore) calves for
           in vitro embryo production
    • Abstract: Publication date: January 2016
      Source:Domestic Animal Endocrinology, Volume 54
      Author(s): E.O.S. Batista, B.M. Guerreiro, B.G. Freitas, J.C.B. Silva, L.M. Vieira, R.M. Ferreira, R.G. Rezende, A.C. Basso, R.N.V.R. Lopes, F.P. Rennó, A.H. Souza, P.S. Baruselli
      This study evaluated the association between plasma anti-Müllerian hormone (AMH) concentrations and in vitro embryo production in Bos indicus (Nelore; experiment 1) and Bos taurus (Holstein; experiment 2) calves superstimulated or not with 140 mg of porcine follicle-stimulating hormone (pFSH; 4 decreasing doses twice daily). Oocytes were recovered from calves aged 2 to 4 mo after receiving gonadotropin stimulation (Nelore, n = 15; Holstein, n = 12) or not (Nelore, n = 15; Holstein, n = 12). Cycling heifers formed a positive control group (n = 15 for Nelore [aged 18–24 mo], n = 10 for Holstein [aged 14–16 mo]). All the calves underwent laparoscopic ovum pickup, and cycling heifers underwent a regular transvaginal ultrasound-guided ovum pickup for oocyte recovery. Immediately before oocyte retrieval, blood samples were taken for subsequent AMH determination (ng/mL). Regardless of the genetic group, calves that received pFSH (3.6 ± 1.1 in Nelore and 4.6 ± 1.2 in Holstein) or did not receive pFSH (3.2 ± 1.0 in Nelore and 2.5 ± 0.8 in Holstein) had greater plasma AMH concentrations (P = 0.01 in Nelore and P = 0.003 in Holstein) than cycling heifers (1.1 ± 0.2 in Nelore and 0.6 ± 0.07 in Holstein). AMH concentrations in calves with or without pFSH were similar in both genetic groups (3.6 ± 1.1 vs 3.2 ± 1.0 in Nelore; 4.6 ± 1.2 vs 2.5 ± 0.8 in Holstein). In calves, positive correlations were observed between plasma AMH concentrations and the numbers of follicles >2 mm (r = 0.86, P < 0.0001 in Nelore; r = 0.78, P < 0.0001 in Holstein), cumulus-oocyte complexes (COCs) retrieved (r = 0.91, P < 0.0001 in Nelore; r = 0.82, P < 0.0001 in Holstein), COCs cultured (r = 0.71, P < 0.0001 in Nelore; r = 0.79, P < 0.0001 in Holstein), and blastocysts produced (r = 0.62, P = 0.0003 in Nelore; r = 0.58, P = 0.009 in Holstein), and these results were independent of pFSH treatment. In conclusion, calves had greater plasma AMH concentrations than cycling heifers. In addition, treatment with pFSH did not influence AMH concentrations in calves, regardless of the genetic group. More importantly, plasma AMH concentrations were positively correlated with the antral follicle population and the number of COCs retrieved, COCs cultured, and blastocysts produced in B indicus and B taurus calves. Therefore, AMH is a promising tool for selecting oocyte donor calves to maximize results during in vitro embryo production.

      PubDate: 2015-09-25T13:43:18Z
  • Potential role for GnRH in the synchronization of follicular emergence
           before the superovulatory Day 0 protocol
    • Abstract: Publication date: January 2016
      Source:Domestic Animal Endocrinology, Volume 54
      Author(s): M.F.A. Balaro, J.F. Fonseca, T.G.B. Barbosa, J.M.G. Souza-Fabjan, L.M. Figueira, T.A. Teixeira, L.R. Carvalheira, F.Z. Brandão
      The ability of gonadotropin-releasing hormone (GnRH) to synchronize ovulation and new follicular wave emergence before a “superovulatory Day 0” protocol was assessed in Santa Inês ewes. For estrus synchronization, a 60-mg medroxyprogesterone acetate sponge was inserted for 6 d. One day before sponge removal, 37.5-μg d-cloprostenol and 300 IU equine chorionic gonadotropin were injected intramuscularly (i.m.). After sponge removal, ewes were assigned to the following 3 groups: (1) GC—1 mL saline at 12 h (n = 10); (2) G24h—0.025-mg lecirelin (GnRH agonist) i.m. at 24 h (n = 10); or (3) G36h—0.025-mg lecirelin i.m. at 36 h (n = 9). Ovarian ultrasonography was conducted to assess follicular dynamics. Blood was collected to determine plasma concentrations of progesterone and estradiol. Females from G36h and GC had a greater (P < 0.05) estrous response than those from the G24h group (78.0 and 90.0 vs 0.0%, respectively). Ewes from G24h and G36h had earlier (P < 0.05) ovulation (48.0 ± 10.2 and 56.7 ± 5.7 h) compared with those from Gc (64.1 ± 9.7 h). The mean number of ovulations per ewe was greater (P < 0.05) in Gc (1.9 ± 0.6) and G36h (2.0 ± 1.0) than G24h (1.2 ± 0.4). Plasma concentrations of progesterone and estradiol differed over time. Follicular growth during the postovulatory day was affected (P < 0.05) by day of the estrus cycle as well as by the interaction (P < 0.05) of treatment and day of the estrus cycle. There was a larger (P < 0.05) population of medium follicles during the first 24 h after the ovulation in G24h compared with Gc, and there was an absence of large follicles in G36h between 36 and 72 h after ovulation. In conclusion, the use of GnRH agonist at 36 h more efficiently synchronized ovulation and promoted the absence of dominant follicles during early diestrus and may be used at the start of superovulatory treatment at 80 h in Santa Inês ewes.

      PubDate: 2015-09-25T13:43:18Z
  • Regulation and localization of vascular endothelial growth factor within
    • Abstract: Publication date: Available online 25 September 2015
      Source:Domestic Animal Endocrinology
      Author(s): M.K. VanKlompenberg, R. Manjarín, C.E. Donovan, J.F. Trott, R.C. Hovey
      The vascular network within the developing mammary gland (MG) grows in concert with the epithelium to prepare for lactation, although the mechanisms coordinating this vascular development are unresolved. Vascular endothelial growth factor A (VEGF-A) mediates angiogenesis and vascular permeability in the MG during pregnancy and lactation, where its expression is upregulated by prolactin. Given our previous finding that late-gestational hyperprolactinemia induced by domperidone (DOM) increased subsequent milk yield from gilts, we sought to establish changes in vascular development during late gestation and lactation in the mammary glands of these pigs as well as determine whether DOM altered MG angiogenesis and the factors regulating it. Gilts received either no treatment (n=6) or DOM (n=6) during late gestation, then had their MG biopsied from late gestation through lactation to assess microvessel density, VEGF-A distribution and mRNA expression, and aquaporin (AQP) gene expression. Microvessel density in the MG was unchanged during gestation then increased between days 2 and 21 of lactation (P < 0.05). The local expression of mRNA for VEGF-A 120 , VEGF-A 147 , VEGF-A 164 , VEGF-A 164 b, VEGF-A 188 , VEGF receptors-1 and -2, and AQP1 and AQP3 all generally increased during the transition from gestation to lactation (P < 0.05). Immunostaining localized VEGF-A to the apical cytoplasm of secretory epithelial cells, consistent with a far greater concentration of VEGF-A in colostrum/milk versus plasma (P < 0.0001). There was no effect of DOM on any of the variables analyzed. In summary, we find that vascular development in the MG increases during lactation in first-parity gilts and that VEGF-A is a part of the mammary secretome. Although late gestational hyperprolactinemia increases milk yield, there was no evidence it altered vascular development.

      PubDate: 2015-09-25T13:43:18Z
  • Intrafollicular expression and potential regulatory role of cocaine- and
           amphetamine-regulated transcript (CART) in the ovine ovary
    • Abstract: Publication date: Available online 16 September 2015
      Source:Domestic Animal Endocrinology
      Author(s): Y. Huang, X.L. Yao, J.Z. Meng, Y. Liu, X.L. Jiang, J.W. Chen, P.F. Li, Y.S. Ren, W.Z. Liu, J.B. Yao, J.K. Folger, G.W. Smith, L.H. Lv
      Follicular growth is regulated by a complex interaction of pituitary gonadotropins with local regulatory molecules. Previous studies demonstrated an important role for cocaine-and amphetamine-regulated transcript (CART) in regulation of granulosa cell estradiol production associated with dominant follicle selection in cattle. However, intra-ovarian expression and actions of CART in other species, including sheep, are not known. The objective of described studies was to investigate expression of CART in sheep follicles and determine effects of CART on indices of ovine granulosa cell function linked to follicular development. Results demonstrated expression of CART mRNA and prominent intra-ovarian localization of CART peptide in granulosa cells of sheep follicles. Granulosa cell CART mRNA was lower, but follicular fluid estradiol concentrations were higher in large (> 5 mm) follicles versus smaller 3-5 mm follicles harvested from sheep ovaries of abattoir origin. CART treatment inhibited FSH-induced estradiol production by cultured ovine granulosal cells and also blocked the FSH-induced increase in granulosa cell numbers. Results demonstrate expression of CART in sheep follicular tissues and suggest potential biological actions of CART which are inhibitory to ovine follicular growth and development.

      PubDate: 2015-09-25T13:43:18Z
  • Insulin: pancreatic secretion and adipocyte regulation
    • Abstract: Publication date: Available online 18 July 2015
      Source:Domestic Animal Endocrinology
      Author(s): L.H. Baumgard, G.J. Hausman, M.V. Sanz Fernandez
      Insulin is the primary acute anabolic coordinator of nutrient partitioning. Hyperglycemia is the main stimulant of insulin secretion, but other nutrients such as specific amino acids, fatty acids, and ketoacids can potentiate pancreatic insulin release. Incretins are intestinal hormones with insulinotropic activity and are secreted in response to food ingestion, thus integrating diet chemical composition with the regulation of insulin release. In addition, prolactin is required for proper islet development, and it stimulates β-cell proliferation. Counterintuitively, bacterial components appear to signal insulin secretion. In vivo lipopolysaccharide infusion acutely increases circulating insulin, which is paradoxical as endotoxemia is a potent catabolic condition. Insulin is a potent anabolic orchestrator of nutrient partitioning, and this is particularly true in adipocytes. Insulin dictates lipid accretion in a dose-dependent manner during preadipocyte development in adipose tissue–derived stromal vascular cell culture. However, in vivo studies focused on insulin's role in regulating adipose tissue metabolism from growing, and market weight pigs are sometimes inconsistent, and this variability appears to be animal, age and depot dependent. Additionally, porcine adipose tissue synthesizes and secretes a number of adipokines (leptin, adiponectin, and so forth) that directly or indirectly influence insulin action. Therefore, because insulin has an enormous impact on agriculturally important phenotypes, it is critical to have a better understanding of how insulin homeostasis is governed.

      PubDate: 2015-09-25T13:43:18Z
  • Pharmacologic analyses of 4 chicken melanocortin-4 receptor mutations
    • Abstract: Publication date: Available online 2 July 2015
      Source:Domestic Animal Endocrinology
      Author(s): Z.-Q. Wang, J.-S. Huang, J.-H. Zhou, S. Lin, X.-F. Jiang, Y.-X. Tao
      The melanocortin-4 receptor (MC4R) is a critical regulator of mammalian food intake and energy expenditure, with receptor activation resulting in decreased food intake and increased energy expenditure. Recently, studies on role of MC4R in regulation of food intake have been extended to other species, such as chicken. Functional study of mutant MC4Rs is important in proving the causal link between MC4R mutation and production traits. Herein, we cloned chicken MC4R (cMC4R) complementary DNA and generated 4 mutant cMC4Rs (Q18H, G21R, S76L, and L299P) by site-directed mutagenesis and measured their expression by flow cytometry. Pharmacologic characteristics were analyzed with binding and signaling assays using 3 agonists. We showed that G21 R had decreased cell surface and total expression (P < 0.05), whereas the other 3 mutants had similar total and cell surface expression levels as wild-type cMC4R. The 4 mutants had either decreased (Q18H, G21R, S76L; P < 0.05) or no (L299P) binding to radiolabeled [Nle4, D-Phe7]-α-melanocyte-stimulating hormone (MSH). In signaling assays, Q18H was constitutively active. Q18H, G21R, and S76L had decreased responses to α-MSH stimulation (P < 0.05). L299P had decreased basal and ligand-stimulated signaling (P < 0.01). Nle4, D-Phe7-MSH was the most potent agonist for cMC4R and therefore would be better suited for further in vivo studies. We conclude that the cloned cMC4R was a functional receptor and provided detailed functional data for these mutations, contributing to a better understanding of cMC4R variants associated with production traits.

      PubDate: 2015-09-25T13:43:18Z
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