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        1 2     

  Subjects -> VETERINARY SCIENCE (Total: 170 journals)
Acta Scientiae Veterinariae     Open Access  
Acta Veterinaria     Open Access  
Acta Veterinaria Brno     Open Access   (1 follower)
Acta Veterinaria Hungarica     Full-text available via subscription   (1 follower)
Acta Veterinaria Scandinavica     Open Access   (1 follower)
Advances in Animal Biosciences     Full-text available via subscription   (5 followers)
Advances in Veterinary Medicine     Full-text available via subscription   (5 followers)
Advances in Veterinary Science and Comparative Medicine     Full-text available via subscription   (8 followers)
American Journal of Animal and Veterinary Sciences     Open Access   (7 followers)
American Journal of Primatology     Hybrid Journal   (5 followers)
American Journal of Veterinary Research     Full-text available via subscription   (15 followers)
Anatomia, Histologia, Embryologia: Journal of Veterinary Medicine Series C     Hybrid Journal   (2 followers)
Animal Behaviour     Hybrid Journal   (129 followers)
Animal Feed Science and Technology     Hybrid Journal   (4 followers)
Animal Health Research Reviews     Hybrid Journal   (4 followers)
Animal Reproduction Science     Hybrid Journal   (4 followers)
Animals     Open Access   (5 followers)
Annales UMCS, Medicina Veterinaria     Open Access  
Annals of Agricultural and Environmental Medicine     Open Access   (1 follower)
Annual Review of Animal Biosciences     Full-text available via subscription   (4 followers)
Anthrozoos : A Multidisciplinary Journal of The Interactions of People & Animals     Full-text available via subscription   (3 followers)
Archives of Animal Nutrition     Hybrid Journal   (3 followers)
Archivos de Medicina Veterinaria     Open Access   (1 follower)
Arquivo Brasileiro de Medicina Veterinária e Zootecnia     Open Access   (1 follower)
Asian Journal of Poultry Science     Open Access   (1 follower)
Australian Equine Veterinarian     Full-text available via subscription   (1 follower)
Australian Veterinary Journal     Hybrid Journal   (10 followers)
Avances en Ciencias Veterinarias     Open Access  
Avian Diseases     Full-text available via subscription   (3 followers)
Avian Diseases Digest     Full-text available via subscription   (2 followers)
Avian Pathology     Hybrid Journal   (1 follower)
Bangladesh Journal of Animal Science     Open Access  
Bangladesh Journal of Veterinary Medicine     Open Access  
BMC Veterinary Research     Open Access   (5 followers)
Brazilian Journal of Veterinary Research and Animal Science     Open Access   (5 followers)
Bulletin of Animal Health and Production in Africa     Full-text available via subscription  
Bulletin of the Veterinary Institute in Pulawy     Open Access  
Canadian Journal of Veterinary Research     Full-text available via subscription   (4 followers)
Case Reports in Veterinary Medicine     Open Access   (3 followers)
Ciência Rural     Open Access   (2 followers)
Companion Animal     Hybrid Journal   (4 followers)
Continental Journal of Animal and Veterinary Research     Open Access   (3 followers)
Continental Journal of Veterinary Sciences     Open Access   (3 followers)
Domestic Animal Endocrinology     Hybrid Journal   (3 followers)
Equine Veterinary Education     Hybrid Journal   (7 followers)
Equine Veterinary Journal     Hybrid Journal   (9 followers)
Ethiopian Veterinary Journal     Open Access  
Eurasian Journal of Veterinary Sciences     Open Access   (1 follower)
Human & Veterinary Medicine - International Journal of the Bioflux Society     Open Access   (5 followers)
ILAR Journal     Hybrid Journal  
In Practice     Full-text available via subscription   (3 followers)
Indian Journal of Animal Sciences     Open Access   (4 followers)
Indian Journal of Veterinary Anatomy     Full-text available via subscription   (3 followers)
International Journal for Agro Veterinary and Medical Sciences     Open Access   (3 followers)
International Journal of Livestock Research     Open Access  
International Journal of Veterinary Science and Medicine     Open Access   (1 follower)
InVet     Open Access  
Irish Veterinary Journal     Open Access   (2 followers)
ISRN Veterinary Science     Open Access   (5 followers)
Journal of Veterinary Science & Technology     Open Access   (3 followers)
Journal of Animal Behaviour and Biometeorology     Open Access   (1 follower)
Journal of Animal Physiology and Animal Nutrition     Hybrid Journal   (3 followers)
Journal of Applied Animal Nutrition     Hybrid Journal   (1 follower)
Journal of Avian Medicine and Surgery     Full-text available via subscription   (4 followers)
Journal of Equine Veterinary Science     Hybrid Journal   (8 followers)
Journal of Exotic Pet Medicine     Full-text available via subscription   (2 followers)
Journal of Experimental and Applied Animal Sciences     Open Access   (1 follower)
Journal of Feline Medicine & Surgery     Hybrid Journal   (3 followers)
Journal of Research in Forestry, Wildlife and Environment     Open Access  
Journal of Small Animal Practice     Hybrid Journal   (8 followers)
Journal of the American Veterinary Medical Association     Full-text available via subscription   (19 followers)
Journal of the Hellenic Veterinary Medical Society     Full-text available via subscription   (1 follower)
Journal of the South African Veterinary Association     Open Access   (1 follower)
Journal of Venomous Animals and Toxins     Open Access   (3 followers)
Journal of Veterinary Advances     Open Access   (4 followers)
Journal of Veterinary Behavior: Clinical Applications and Research     Hybrid Journal   (3 followers)
Journal of Veterinary Cardiology     Full-text available via subscription   (4 followers)
Journal of Veterinary Diagnostic Investigation     Hybrid Journal   (4 followers)
Journal of Veterinary Emergency and Critical Care     Hybrid Journal   (9 followers)
Journal of Veterinary Internal Medicine     Hybrid Journal   (11 followers)
Journal of Veterinary Medical Education     Partially Free   (8 followers)
Journal of Veterinary Medicine     Open Access   (2 followers)
Journal of Veterinary Medicine and Animal Health     Open Access  
Journal of Veterinary Pharmacology and Therapeutics     Hybrid Journal   (4 followers)
Journal of Veterinary Science & Medical Diagnosis     Full-text available via subscription  
Journal of Zoo and Aquarium Research     Open Access  
Journal of Zoo and Wildlife Medicine     Full-text available via subscription   (2 followers)
Kenya Veterinarian     Full-text available via subscription  
kleintier konkret     Hybrid Journal  
Livestock     Hybrid Journal  
Macedonian Veterinary Review     Open Access   (3 followers)
MEDIA PETERNAKAN - Journal of Animal Science and Technology     Open Access   (1 follower)
Medical Mycology     Open Access   (2 followers)
Medical Mycology Case Reports     Open Access  
Microbes and Health     Open Access   (2 followers)
New Zealand Veterinary Journal     Full-text available via subscription   (7 followers)
New Zealand Veterinary Nurse     Full-text available via subscription   (2 followers)
Nigerian Veterinary Journal     Open Access  
Onderstepoort Journal of Veterinary Research     Open Access   (2 followers)
Open Access Animal Physiology     Open Access   (2 followers)

        1 2     

Domestic Animal Endocrinology    [5 followers]  Follow    
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
     ISSN (Print) 0739-7240
     Published by Elsevier Homepage  [2556 journals]   [SJR: 0.75]   [H-I: 50]
  • Initiation of active immunization against testosterone during early
           puberty alters negative feedback regulation of the
           hypothalamic-pituitary-testicular axis in rabbits
    • Abstract: Publication date: Available online 12 April 2014
      Source:Domestic Animal Endocrinology
      Author(s): X.F. Han , W. Cheng , Z.Y. Chen , X.G. Du , X.H. Cao , X.Y. Zeng
      To investigate effects of anti-testosterone immunization, initiated during early puberty, on hypothalamic-pituitary-testicular feedback in rabbits, 16 early pubertal male rabbits were randomly allocated into two groups (n = 8), control or immunized against testosterone-3(O-carboxymethyl)oxime-BSA in Freund’s adjuvant at 4 mo of age (with a booster immunization 4 wk later). Blood samples (for antibody titers and hormone concentrations) were collected at 2- or 4-wk intervals after immunization. Compared to controls, anti-testosterone immunization triggered: a substantial and sustained antibody response (P < 0.01); increases in serum concentrations of LH and testosterone, and testis weight and volume (P < 0.05); hyperplasia of testicular interstitial tissue with clustered and hypertrophic Leydig cells; and greater (P < 0.05) enzyme protein and mRNA expression levels for testicular cholesterol side-chain cleavage cytochrome P-450, 17α-hydroxylase cytochrome P-450 and 3β-dydroxysteroid dehydrogenase. Furthermore, immunoneutralization of testosterone up-regulated mRNA expressions for genes in sex steroid negative feedback loops, including androgen receptor (AR), estrogen receptor alpha (ER-α), kisspeptin encoded gene (kiss-1) and kisspeptin receptor (GPR54) and GnRH in the hypothalamic arcuate nucleus, GnRH receptor and LH-β in pituitary, and AR, inhibin-α and βA subunits in testes (P < 0.05). However, immunization did not affect mRNA expressions for FSH-β, AR and ER-α in pituitary, or ER-α in testes. We concluded that anti-testosterone immunization in male rabbits, initiated during early puberty, increased GnRH mRNA expression and in turn LH synthesis by reducing testicular feedback signaling. Reduction of direct steroidal effects on the testis may also have increased testosterone secretion. Consequently, there was accelerated testicular development during puberty and enhanced testicular function after puberty, which likely conferred prolonged reproductive advantages.

      PubDate: 2014-04-14T17:48:51Z
  • Pivotal Roles for Hormonally Regulated Expression of the HEP21 Gene in the
           Reproductive Tract of Chickens for Oviduct Development and in Ovarian
    • Abstract: Publication date: Available online 5 April 2014
      Source:Domestic Animal Endocrinology
      Author(s): W. Lim , G. Song
      Hen egg protein (HEP21) is a 21 kDa secreted protein and has a single copy of the Ly6/uPAR domain. Although HEP21 is expressed primarily in the chicken oviduct, its biological function(s) in the reproductive system of chickens is not known. Thus, in the present study, we investigated expression patterns of HEP21 with respect to hormonal regulation, oviduct development, changes in expression in laying hens undergoing induced molting, and in the development of ovarian carcinogenesis in laying hens. Results of current study indicated that HEP21 mRNA expression increased (P < 0.001) in the chicken oviduct in response to estrogen. In situ hybridization analyses revealed expression of HEP21 mRNA predominantly in glandular (GE) and luminal epithelia of the magnum of the chicken oviduct in response to estrogen. The expression of HEP21 mRNA decreased (P < 0.001) as the oviduct regressed during induced molting and increased (P < 0.001) with recrudescence of the oviduct following molting. HEP21 mRNA was most abundant in GE of the oviduct during recrudescence, but not during oviduct regression following induced molting. Moreover, we found abundant expression of HEP21 in GE of cancerous ovaries, but not in normal ovaries of hens. Collectively, results of present study suggest that HEP21 is an estrogen-responsive gene in the oviduct of hens that likely regulates development of the chicken oviduct, and egg production and formation. Furthermore, there is increased expression of HEP21 in epithelial-derived ovarian cancer suggesting that HEP21 could be used for diagnosis and monitoring carcinogenesis in laying hens and in women.

      PubDate: 2014-04-10T13:41:05Z
  • A novel monoclonal antibody-based ELISA to determine luteinizing hormone
           in bovine plasma
    • Abstract: Publication date: Available online 5 April 2014
      Source:Domestic Animal Endocrinology
      Author(s): V. Borromeo , A. Berrini , F. De Grandi , F. Cremonesi , N. Fiandanese , P. Pocar , C. Secchi
      The development of a novel ELISA for determining luteinizing hormone (LH) in bovine plasma is described. Anti-bovine LH (bLH) monoclonal antibodies (mAbs) were produced and characterized. One mAb recognizing the bLH β subunit was used for immuno-affinity purification of substantial amounts of biologically active bLH from pituitary glands. The purified bLH in combination with two anti-bLH β subunit mAbs was used to develop a sandwich ELISA, which satisfied all the criteria required to investigate LH secretory patterns in the bovine species. The ELISA standard curve was linear over the range 0.05-2.5 ng/mL, and the assay proved suitable for measuring bLH in plasma without any prior treatment of samples. Cross-reactivity and recovery tests confirmed the specificity of the method. The intra- and inter-assay coefficients of variation ranged between 3.41% and 9.40%, and 9.29% and 15.84%, respectively. The analytical specificity of the method was validated in vivo by provocative tests for LH in heifers, using the LH releasing peptide GnRH. In conclusion, the adoption of mAbs for this ELISA for coating the wells and labeling, combined with the easy one-step production of reference bLH, ensures long-term continuity in large-scale measurements of LH in the bovine species.

      PubDate: 2014-04-10T13:41:05Z
  • Reducing exposure to long days from 75 to 30 days of extra-light treatment
           does not decrease the capacity of male goats to stimulate ovulatory
           activity in seasonally anovulatory females
    • Abstract: Publication date: Available online 20 March 2014
      Source:Domestic Animal Endocrinology
      Author(s): José Luis Ponce , Hillary Velázquez , Gerardo Duarte , Marie Bedos , Horacio Hernández , Matthieu Keller , Philippe Chemineau , José Alberto Delgadillo
      The response of male goats exposed to different durations of long days (LD) during an extra-light treatment in autumn-winter, and their ability to induce ovulations in seasonally anovulatory goats were investigated in two experiments. In Experiment 1, control males were exposed to natural photoperiod (n = 5), whereas four additional groups (n = 5/group) were exposed to 16 h of light per d during 75, 45, 30, or 15 d of LD. In the four groups, photoperiodic treatments ended on January 15th. Plasma concentrations of testosterone were determined in blood samples obtained once a week from October 15th to May 30th. The rise of testosterone levels occurred earlier in males from the 75-LD and 45-LD groups than in those from the 30-LD, 15-LD and control groups (P < 0.05). In addition, the time during which levels of testosterone remained above 5 ng/mL was longer in males from the 75-LD and 45-LD than in those from the 30-LD and 15-LD groups (P < 0.05). In experiment 2, a group of anovulatory goats (n = 13) was isolated from males, while three additional groups were put in contact during 15 d with males previously exposed to 75, 45 or 30 days of LD (n = 25, 27, and 26 females/group, respectively and n = 3 males per group). The proportion of goats that ovulated was higher in the 3 groups in contact with the photo-stimulated males (range: 88-92 %) than in the group isolated from them (0 %; P < 0.05). The proportion of pregnant females did not differ between the three groups of does in contact with photo-stimulated males (range: 78-92%; P > 0.05). We conclude that, in our experimental conditions, a photoperiodic treatment as short as 30 d of LD during autumn-winter, stimulated testosterone secretion of bucks during their period of sexual rest and rendered them able to induce ovulations in seasonal anestrous goats and to obtain pregnancies in these females.

      PubDate: 2014-03-20T18:40:46Z
  • Isolation of endothelial cells and pericytes from swine corpus luteum
    • Abstract: Publication date: Available online 12 March 2014
      Source:Domestic Animal Endocrinology
      Author(s): G. Basini , I. Falasconi , S. Bussolati , S. Grolli , R. Ramoni , F. Grasselli
      From an angiogenesis perspective, the ovary offers a unique opportunity to study the physiological development of blood vessels. The first purpose of this work was to set up a protocol for the isolation of pig corpus luteum endothelial cells, which were characterized by both morphological parameters and the expression of typical molecular markers; we also verified their ability to form capillary-like structures in a three-dimensional matrix, their response to hypoxia and their migration in the presence of Vascular Endothelial Growth Factor (VEGF). The effectiveness of our isolation protocol was confirmed by the characteristic “cobblestone shape” of isolated cells at confluence as well as their expression of all the examined endothelial markers. Our data also showed a significant cell production of VEGF and nitric oxide (NO). Isolated endothelial cells were also responsive to hypoxia by increasing the expression and production of VEGF and decreasing that of NO. In the angiogenesis bioassay, cells displayed the ability of forming capillary-like structures and also exhibited a significant migration in the scratch test. Our data suggest that the isolation of luteal endothelial cells represents a promising tool in experiments designed to clarify the biology of the angiogenic process. Furthermore, we have demonstrated that the isolated population comprises a subset of cells with a multidifferentiative capacity towards the chondrocytic and adipocytic phenotypes. These data suggest the presence of a perivascular or adventitial cell niche in the vascular wall of the corpus luteum populated with cells showing mesenchymal stem cell-like features, as already demonstrated the adipose tissue and endometrium.

      PubDate: 2014-03-16T12:06:12Z
  • Administration of estradiol benzoate prior to insemination could skew
           secondary sex ratio toward males in Holstein dairy cows
    • Abstract: Publication date: Available online 15 March 2014
      Source:Domestic Animal Endocrinology
      Author(s): S.R. Emadi , A. Rezaei , M. Bolourchi , P. Hovareshti , V. Akbarinejad
      The present study was conducted to investigate the effect of estradiol benzoate administration prior to insemination on secondary sex ratio (proportion of male calves at birth) in Holstein dairy cows. Cows (n = 1647) were randomly assigned to two experimental groups by parity over a one-year period. Cows in the control group (n = 827; 232 primiparous and 595 multiparous cows) received two administrations of PGF2α (500 μg) 14 d apart started at 30 to 35 d postpartum. Twelve d after the second PGF2α injection, cows received GnRH (100 μg), followed by administration of PGF2α 7 d later. Cows in the treatment group (n = 820; 238 primiparous and 582 multiparous cows) received the same hormonal administrations as the cows in the control group. Additionally, cows in the treatment group received estradiol benzoate (1 mg) one day after the third PGF2α injection. Estrus detection by visual observation was started one day after the third PGF2α injection and after estradiol administration in the control (for 6 d) and treatment (for 36 h) groups, respectively. Artificial insemination was carried out 12 h after observation of standing estrus. Exposure of cows to heat stress at conception was determined based on temperature-humidity index. Estrus detection rate was lower in primiparous than in multiparous cows (P < 0.05), but conception rate was higher in primiparous versus multiparous cows (P < 0.05). Estradiol administration improved estrus detection rate and fertility (P < 0.05); moreover, it increased secondary sex ratio (adjusted odds ratio: 1.645; P = 0.017). Exposure to heat stress diminished heat detection rate and fertility (P < 0.05), and altered secondary sex ratio toward males (adjusted odds ratio: 2.863; P = 0.012). In conclusion, the present study revealed that estradiol administration before insemination could improve fertility and increase the probability of calves being male in Holstein dairy cows. Moreover, the results showed that cows exposed to heat stress around conception had diminished fertility and increased secondary sex ratio.

      PubDate: 2014-03-16T12:06:12Z
  • Contents
    • Abstract: Publication date: April 2014
      Source:Domestic Animal Endocrinology, Volume 47

      PubDate: 2014-03-10T16:45:32Z
  • Evaluation of a high-yield technique for pancreatic islet isolation from
           deceased canine donors
    • Abstract: Publication date: April 2014
      Source:Domestic Animal Endocrinology, Volume 47
      Author(s): D. Vrabelova , C.A. Adin , A. Kenzig , C. Gilor , F. Xu , J.L. Buss , A. Rajab
      Type 1 diabetes mellitus is one of the most frequently diagnosed endocrinopathies in dogs, and prevalence continues to increase. Pancreatic islet transplantation is a noninvasive and potentially curative treatment for type 1 diabetes mellitus. Institution of this treatment in dogs will require a readily available source of canine islets. We hypothesized that clinically acceptable islet yield and purity could be achieved by using deceased canine donors and standard centrifugation equipment. Pancreata were procured from dogs euthanized for reasons unrelated to this study. Initial anatomic studies were performed to evaluate efficacy of pancreatic perfusion. Infusion into the accessory pancreatic duct resulted in perfusion of approximately 75% of the pancreas. Additional cannulation of the distal right limb of the pancreas allowed complete perfusion. Collagenase digestion was performed with a Ricordi chamber and temperature-controlled perfusion circuit. Islets were separated from the exocrine tissue with the use of a discontinuous density gradient and a standard laboratory centrifuge. After isolation, islet yield was calculated and viability was assessed with dual fluorescent staining techniques. Islet isolation was completed in 6 dogs. Median (interquartile range) islet yield was 36,756 (28,527) islet equivalents per pancreas. A high degree of islet purity (percentage of endocrine tissue; 87.5% [10%]) and viability (87.4% [12.4%]) were achieved. The islet yield achieved with this technique would require approximately 1 pancreas per 5 kg body weight of the recipient dog. Purity and viability of the isolated islets were comparable with those achieved in human islet transplantation program. According to initial results, clinically relevant islet yield and quality can be obtained from deceased canine donors with the use of standard laboratory equipment.

      PubDate: 2014-03-10T16:45:32Z
  • Editorial Board
    • Abstract: Publication date: April 2014
      Source:Domestic Animal Endocrinology, Volume 47

      PubDate: 2014-03-10T16:45:32Z
  • Influence of feeding status, time of the day and season on baseline ACTH
           and the response to TRH-stimulation test in healthy horses
    • Abstract: Publication date: Available online 5 March 2014
      Source:Domestic Animal Endocrinology
      Author(s): E. Diez de Castro , I. Lopez , B. Cortes , C. Pineda , B. Garfia , E. Aguilera-Tejero
      Equine pituitary pars intermedia function can be assessed by measurement of baseline and TRH-induced concentrations of ACTH; however, these measurements may be affected by the environment. Therefore, a prospective observational study evaluated the influence of a) feeding, b) time of the day, and c) season on baseline and TRH-induced concentrations of ACTH in healthy horses. Baseline ACTH was measured in 50 horses before and 2 h after feeding. Six research horses were subjected to a crossover study in which 6 TRH tests were performed in 2 different seasons, March-April (MA) and July-September (JS), at 2 different times of the day, 8:00 and 20:00 h, and, under 2 different conditions relative to feeding status, fasted and 2 h after feeding. Differences between fasted and fed horses were found in baseline ACTH, 17.1 ± 1.8 vs. 46.1 ± 7.6 pg/mL (P = 0.003) and TRH-stimulated ACTH: 124.1 ± 21.3 vs. 192.6 ± 33.1 pg/mL (P = 0.029) at 10 min, and 40.1 ± 4.9 vs. 73.2 ± 13.4 pg/mL (P = 0.018) at 30 min post TRH injection. No differences were found between tests performed at different times of the day. Basal ACTH concentrations were greater in JS than in MA, 17.1 ± 1.8 pg/mL vs. 11.9 ± 0.6 pg/mL (P = 0.006). A seasonal influence was also found in stimulated ACTH values, which were much greater in JS 122.7 ±3 6.7 pg/mL vs. 31.2 ± 7.4 pg/mL, at 10 min (P = 0.03) and 39.0 ± 7.2 pg/mL vs. 19.8 ± 3.1 pg/mL, at 30 min (P = 0.03). In addition to season, feeding is a potential confounding factor when measuring baseline or stimulated ACTH in horses. In conclusion, feeding status should be standardized for the diagnosis of equine PPID.

      PubDate: 2014-03-05T18:34:20Z
  • Influence of season and nutritional status on the direct effects of
           leptin, orexin-A and ghrelin on LH and GH secretion in the ovine pituitary
           explant model
    • Abstract: Publication date: Available online 5 March 2014
      Source:Domestic Animal Endocrinology
      Author(s): K. Kirsz , M. Szczesna , K. Dudek , P.M. Bartlewski , D.A. Zieba
      The aim of this study was to examine whether leptin (anorexigenic peptide), orexin-A and ghrelin (orexigenic peptides) could directly (i.e., independently of hypothalamic influences) affect the secretion of luteinizing hormone (LH) and growth hormone (GH) by adenohypophyseal (AP) explants obtained from normally fed or fasted (48 h) ewes during the breeding and non-breeding seasons. In addition, a specific ovine leptin antagonist (SLAN-3) was used to assess the interactions between leptin and ghrelin/orexin-A. Pituitary glands from 16 ovariectomized Polish Longwool ewes that had received estradiol-releasing subcutaneous implants were collected in the breeding (November; n = 8) and non-breeding seasons (May; n = 8). The AP explants were incubated for 240 min in a gas-liquid interface and treated with leptin (50 ng/mL), ghrelin (100 ng/mL), orexin-A (100 ng/mL), and SLAN-3 (500 ng/mL) with orexin-A or ghrelin. Treatments with leptin and SLAN-3 + orexin-A increased (P < 0.05) LH concentrations in the cultures of AP explants from fasted animals in the breeding season. Orexin-A increased (P < 0.05) LH secretion by AP explants from both fasted and fed animals in the breeding season. Ghrelin stimulated (P < 0.05) GH secretion by AP explants collected from fasted animals in non-breeding season and from normally fed ewes in both seasons. Leptin decreased (P < 0.05) GH secretion by AP explants collected from fasted ewes in both seasons and from non-fasted ewes in the breeding season. However, the treatment with SLAN-3 + ghrelin resulted in greater (P < 0.05) GH concentrations compared with leptin treatment of AP explants from fasted ewes in the breeding season and from normally fed ewes in non-breeding season. In summary, leptin, orexin-A and ghrelin exerted direct effects on AP secretory function in an ex situ model, and both the reproductive season and nutritional status of the animals impinged on the direct effects of the peptides on LH and GH release. Specifically, orexin-A was more potent than leptin in directly stimulating LH secretion in cycling ewes, whereas ghrelin and leptin generally had opposing effects on the secretory function of somatotrophs in sheep.

      PubDate: 2014-03-05T18:34:20Z
  • Nursing supports neonatal porcine testicular development
    • Abstract: Publication date: Available online 5 March 2014
      Source:Domestic Animal Endocrinology
      Author(s): K.M. Rahman , J.E. Lovich , C. Lam , M.E. Camp , A.A. Wiley , F.F. Bartol , C.A. Bagnell
      The lactocrine hypothesis suggests a mechanism whereby milk-borne bioactive factors delivered to nursing offspring affect development of neonatal tissues. The objective of this study was to assess whether nursing affects testicular development in neonatal boars as reflected by: (1) Sertoli cell number and proliferation measured by GATA-4 expression and proliferating cell nuclear antigen (PCNA) immunostaining patterns; (2) Leydig cell development and steroidogenic activity as reflected by insulin-like factor 3 (INSL3) and P450 side chain cleavage (scc) enzyme expression; and (3) expression of estrogen receptor-alpha (ESR1), vascular endothelial growth factor (VEGF) A, and relaxin family peptide receptor (RXFP) 1. At birth, boars were randomly assigned (n = 6 - 7/group) to nurse ad libitum or to be pan fed porcine milk replacer for 48 h. Testes were collected from boars at birth, prior to nursing, and from nursed and replacer-fed boars at 50 h on postnatal day (PND) 2. Sertoli cell PCNA labeling index increased (P < 0.01) from birth to PND 2 in nursed, but not in replacer-fed boars. Sertoli cell number and testicular GATA-4 protein levels increased (P < 0.01) from PND 0 to PND 2 only in nursed boars. Neither age nor nursing affected testicular INSL3, P450scc, ESR1, or VEGFA levels. However, testicular RXFP1 levels increased (P < 0.01) with age and were greater in replacer-fed boars on PND 2. Results suggest that nursing supports neonatal porcine testicular development and provide additional evidence for the importance of lactocrine signaling in pigs.

      PubDate: 2014-03-05T18:34:20Z
  • Relationship of follicle size and concentrations of estradiol among cows
           exhibiting or not exhibiting estrus during a fixed-time AI protocol
    • Abstract: Publication date: Available online 15 February 2014
      Source:Domestic Animal Endocrinology
      Author(s): G.A. Perry , O.L. Swanson , E.L. Larimore , B.L. Perry , G.D. Djira , R.A. Cushman
      Cows exhibiting estrus near the time of fixed-time AI had greater pregnancy success than cows showing no estrus. The objective of these studies were to determine the relationship between follicle size and peak estradiol concentration between cows that did or did not exhibit estrus during a fixed-time AI protocol. Ovulation was synchronized in beef cows by applying the CO-Synch protocol [GnRH (100 μg) on d -9, PGF2α (25 mg) on d -2, and a second injection of GnRH 48 h after PGF2α (d 0)] to both suckled (Exp.1) and non-suckled (Exp.2) cows. Follicle size (d 0) and ovulation (d 2) was determined by ultrasonography. Blood samples were collected every 3 or 4 h beginning at time of PGF2α injection (0 h). Estrus was detected by visual observation with the aid of estrus-detection patches, and cows that ovulated were classified as exhibited estrus (n = 46) or did not exhibit estrus (n = 63). In both suckled and non-suckled cows, there was a positive relationship between all cows (P < 0.05) and among those that exhibited estrus (P < 0.05), between follicle size and peak estradiol concentration, but no linear relationship (P > 0.50) between follicle size and peak estradiol concentration was observed among cows not exhibiting estrus. Cows that exhibited estrus had greater (P < 0.01) peak estradiol concentrations than cows that did not exhibit estrus. Suckled cows exhibiting standing estrus had greater (P < 0.001) preovulatory concentrations of estradiol beginning 6 h (replicate 1) or4 h (replicate 2) after the injection of PGF2α on day -2 compared with cows not exhibiting standing estrus. Non-suckled cows exhibiting standing estrus had greater (P < 0.001) preovulatory concentrations of estradiol beginning at the injection of PGF2α on day -2 compared with cows not exhibiting standing estrus. Furthermore, cows that exhibited estrus had an increased (P < 0.01) rate in the rise in concentrations of estradiol following the PGF2α to peak estradiol than cows not exhibiting estrus. In summary, follicle diameter had a positive relationship with peak concentrations of estradiol, but only among cows that exhibited standing estrus, and estradiol increased earlier in cows that exhibited estrus compared to cows that did not.

      PubDate: 2014-02-19T07:21:54Z
  • Myostatin alters glucose transporter-4 (GLUT4) expression in bovine
           skeletal muscles and myoblasts isolated from double muscled (DM) and
           normal muscled (NM) Japanese shorthorn cattle
    • Abstract: Publication date: Available online 10 February 2014
      Source:Domestic Animal Endocrinology
      Author(s): H. Takahashi , K. Sato , T. Yamaguchi , M. Miyake , H. Watanabe , Y. Nagasawa , E. Kitagawa , S. Terada , M. Urakawa , M.T. Rose , C.D. McMahon , K. Watanabe , S. Ohwada , T. Gotoh , H. Aso
      The purpose of this study was to determine whether myostatin alters glucose transporter-4 (GLUT4) expression in bovine skeletal muscles and myoblasts isolated from double muscled (DM) and normal muscled (NM) Japanese Shorthorn cattle. Plasma concentrations of glucose were lower in DM cattle than in NM cattle (P < 0.01). The expression of GLUT4 mRNA in the skeletal muscle ex vivo as well as in myoblasts at 72 h after differentiation in vitro was higher in DM cattle than in NM cattle (P < 0.01). In contrast, the NM and DM cattle did not differ with respect to skeletal muscle expression of GLUT1 and myocyte enhancer factor-2c (MEF2c), a transcription factor of GLUT4. In differentiated myoblasts, the expression of GLUT1, GLUT4 and MEF2c mRNAs was greater in DM cattle than in NM cattle (P < 0.01). In the presence and absence of insulin, glucose uptake in myoblasts was increased in DM cattle relative to that of NM cattle (P < 0.01). The addition of myostatin decreased the expression of GLUT4 and MEF2c mRNAs in DM myoblasts (P < 0.05). Results of the present study suggest that myostatin inhibits the expression of GLUT4 mRNA possibly via MEF2c, and that the greater ability of the DM cattle to produce muscle relative to the NM cattle may be due to their greater sensitivity to insulin and greater utilization of glucose.

      PubDate: 2014-02-14T20:33:01Z
  • Two or 24 h of daily contact with sexually active males results in
           different profiles of LH secretion that both lead to ovulation in
           anestrous goats
    • Abstract: Publication date: Available online 14 February 2014
      Source:Domestic Animal Endocrinology
      Author(s): M. Bedos , G. Duarte , J.A. Flores , G. Fitz-Rodríguez , H. Hernández , J. Vielma , I.G. Fernández , P. Chemineau , M. Keller , J.A. Delgadillo
      Two experiments were conducted to a) determine whether sexually active males are able to stimulate the sexual activity of anestrous female goats when duration of contact is reduced to an intermittent contact shorter than 4 daily h and b) to compare the pattern of secretion of LH when anestrous goats are exposed either permanently or intermittently to males. In the first experiment, 4 groups of anovulatory goats were exposed to sexually active males for 24, 4, 2, or 1 h/d during 15 consecutive d, while control females remained isolated. More than 89% of females in the groups exposed to the sexually active bucks ovulated, whereas only 5% did so in the control group (P < 0.001). However, the proportion of females ovulating before day 4 was greater in the 2, 4 or 24-h contact groups than in the control, whereas it did not differ between the control group and the 1-h contact group (P = 0.02, < 0.001, < 0.001 and 0.23, respectively). In a second experiment, 3 groups of anovulatory goats were exposed permanently (24 h/d) or intermittently (2 h/d) to bucks during 5 d or remained isolated. We found that pulsatility of LH increased in the intermittent and permanent contact groups after males were introduced to females (P = 0.05); this pulsatility of LH remained elevated in the permanent-contact group, whereas it decreased in the intermittent-contact group, once the male was removed (P = 0.32 and 0.05, respectively). We conclude that 1 or 2 daily h of contact with sexually active males is sufficient to stimulate ovulatory activity in anovulatory goats; however, ovulation is obtained through a different pattern of secretion of LH.

      PubDate: 2014-02-14T20:33:01Z
  • Gonadectomy-related adrenocortical tumors in ferrets demonstrate increased
           expression of androgen and estrogen synthesizing enzymes together with
           high inhibin expression
    • Abstract: Publication date: Available online 14 February 2014
      Source:Domestic Animal Endocrinology
      Author(s): M.K. de Jong , E.E.M. ten Asbroek , A.J. Sleiderink , A.J. Conley , J.A. Mol , N.J. Schoemaker
      The two objectives of this study were to 1) measure by qPCR the expression of genes involved in steroid and inhibin synthesis in adrenocortical tumors of gonadectomized ferrets and 2) localize by immunohistochemistry several proteins that are key to adrenal steroidogenesis. Relative to the control adrenals, expression of the mRNAs encoding StAR, CYP11A (P = 0.019), CYP21 (P = 0.01) and 3ß-HSD (P = 0.004), all involved in the synthesis of mineralocorticoids and glucocorticoids, was decreased in the adrenocortical tumors. In contrast, expression of cytochrome B5 (CytB5; P = 0.0001) and aromatase (P = 0.003), involved in androgen and estrogen synthesis, and both inhibin α-subunit (P = 0.002) and ßB-subunit (P = 0.001) were upregulated. In tumors immunostaining of CYP21 was low whereas staining of Cyp17 and CytB5, necessary for androgen synthesis, was present. It is concluded that ferret adrenocortical tumors express genes for androgen production. In addition, the expression of aromatase as well as inhibin suggests an even more gonadal differentiation which is reminiscent to the fact that both gonads and adrenals are derived from a common urogenital primordial cell.

      PubDate: 2014-02-14T20:33:01Z
  • Energy and metabolic sensing G protein-coupled receptors during
           lactation-induced changes in energy balance
    • Abstract: Publication date: Available online 7 February 2014
      Source:Domestic Animal Endocrinology
      Author(s): P. Friedrichs , B. Saremi , S. Winand , J. Rehage , S. Dänicke , H. Sauerwein , M. Mielenz
      The free fatty acid receptor (FFA) 1, FFA2, FFA3 and hydroxy-carboxylic acid receptor (HCA)2 are G protein-coupled receptors, acting as energy and metabolic sensors. Herein, we characterized the tissue-specific mRNA abundance of genes encoding for these receptors at different stages of lactation. In addition, potential effects of supplementation with or without conjugated linoleic acids (CLA) were tested. Tissues from pluriparous cows (subcutaneous adipose tissue (SAT) and liver) and from primiparous cows (3 SAT locations, 3 visceral adipose tissues (VAT), liver, mammary gland and skeletal muscle) were used from 2 separate trials. In primiparous cows the mRNA abundance of all receptors (FFA3 was not detectable by the applied protocol in muscle and udder) was lowest in muscle (P < 0.05). With exception of FFA1, gene expression of the investigated receptors was higher in AT than in the non-AT. Expression of FFA1 in liver (P < 0.03), of FFAR2 in SAT (P < 0.01) and HCA2 in SAT (P < 0.01) from pluriparous cows changed during the observation period (days -21 to d 252 relative to parturition). The correlation between mRNA abundance of HCA2 and peroxisome proliferator-activated receptor γ (PPARG) and likewise PPARG2 (P < 0.01) in SAT indicates a link between HCA2 and PPARG. Differences in receptor mRNA abundance between the CLA-fed and the control animals were scarce and limited to HCA2 and FFA1 in 1 and 2 time points, respectively (less hepatic HCA2 mRNA in CLA-fed pluriparous cows, and greater FFA1 mRNA abundance in 2 VAT depots in CLA-treated primiparous cows). In view of the metabolic changes occurring during the different phases of lactation, in particular the altered concentrations of non-esterified fatty acids (NEFA) and β -hydroxybutyrate (BHB) acting as receptor ligands, the longitudinal, tissue-specific characterization provided herein allows for a first insight into the regulation of these receptors at the gene expression level.

      PubDate: 2014-02-10T07:28:27Z
  • Impact of maternal physical activity during gestation on porcine fetal,
           neonatal, and adolescent ovarian development
    • Abstract: Publication date: Available online 7 February 2014
      Source:Domestic Animal Endocrinology
      Author(s): S.L. Kaminski , A.T. Grazul-Bilska , E.K. Harris , E.P. Berg , K.A. Vonnahme
      To determine how exercise from mid to late (days 40 to 104) gestation impacts offspring body, uterine and ovarian weight, and ovarian cell proliferation at three different developmental stages, Yorkshire gilts were either exercised by walking (EX) or not exercised (CON). In parity one ovaries and uteri were collected from the heaviest (H) and lightest (L) neonates, and adolescent (6 mo) offspring. In parity two, mothers were assigned the same treatment groups, and ovaries and uteri were collected from H and L fetuses on day 94 of gestation. Body weight was greater (P < 0.02) for H than L fetuses and neonates but not affected by EX-treatment at any developmental stage. Ovarian weight in L but not H neonates was greater (P < 0.02) in EX than CON. Labeling index (LI; percentage of proliferating cells) was greater (P < 0.01) in cortex than medulla regions of fetal and neonatal ovaries. In fetal ovaries, EX enhanced LI (P < 0.01), and LI was greater (P < 0.01) in H compared to L offspring. In adolescent ovaries, LI was greatest (P < 0.01) in healthy antral and least in atretic antral follicles, and LI was greater (P < 0.01) in granulosa than theca cells of healthy antral follicles. Thus, exercise increased LI in fetal but not neonatal or adolescent ovaries. While maternal exercise during gestation influences fetal and neonatal ovarian development, impacts on fertility remain unknown.

      PubDate: 2014-02-10T07:28:27Z
  • Expression and localization of ghrelin and its functional receptor in
           corpus luteum during different stages of estrous cycle and the modulatory
           role of ghrelin on progesterone production in cultured luteal cells in
    • Abstract: Publication date: Available online 21 January 2014
      Source:Domestic Animal Endocrinology
      Author(s): M. Gupta , S.S. Dangi , V.S. Chouhan , I. Hyder , V. Babitha , V.P. Yadav , F.A. Khan , A. Sonwane , G. Singh , G.K. Das , A. Mitra , S. Bag , M. Sarkar
      Evidence obtained during recent years provided insight into the regulation of corpus luteum (CL) development, function and regression by locally produced ghrelin. The present study was carried out to evaluate expression and localization of ghrelin and its receptor (GHS-R1a) in bubaline CL during different stages of the estrous cycle and to investigate the role of ghrelin on progesterone (P4) production along with mRNA expression of P4 synthesis intermediates. The mRNA and protein expression of ghrelin and GHS-R1a was significantly greater in mid and late luteal phases. Both factors were localized in luteal cells, exclusively in the cytoplasm. Immunoreactivity of ghrelin and GHS-R1a was greater during mid and late luteal phases. Luteal cells were cultured in vitro and treated with ghrelin each at 1, 10 and 100 ng/mL concentrations for 48 h after obtaining 75-80% confluence. At a dose of 1 ng/mL, there was no significant difference in progesterone secretion between control and treatment group. At 10 and 100 ng/mL there was a decrease (P< 0.05) in progesterone concentration, cytochrome P45011A1 (CYP11A1) and 3beta-hydroxysteroid dehydrogenase (3β-HSD) mRNA expression and localization. There was no difference in mRNA expression of steroidogenic acute regulatory protein (StAR) between control and treatment group. In summary, the present study provided evidence that ghrelin and its receptor are expressed in bubaline CL and are localized exclusively in the cell cytoplasm and ghrelin has an inhibitory effect on P4 production in buffalo.

      PubDate: 2014-01-22T07:42:07Z
  • The epidermal growth factor receptor is required for estradiol-stimulated
           bovine satellite cell proliferation
    • Abstract: Publication date: Available online 19 January 2014
      Source:Domestic Animal Endocrinology
      Author(s): B.C. Reiter , E. Kamanga-Sollo , M.S. Pampusch , M.E. White , W.R. Dayton
      The objective of this study was to assess the role of the epidermal growth factor receptor (EGFR) in estradiol-17β (E2)-stimulated proliferation of cultured bovine satellite cells (BSC). Treatment of BSC cultures with AG1478 (a specific inhibitor of EGFR tyrosine kinase activity) suppresses E2-stimulated BSC proliferation ( P < 0.05). Additionally, E2-stimulated proliferation is completely suppressed (P < 0.05) in BSC in which EGFR expression is silenced by treatment with EGFR small interfering RNA (siRNA). These results indicate that EGFR is required in order for E2 to stimulate proliferation in BSC cultures. Both AG1478 treatment and EGFR silencing also suppress LR3-IGF-1- (an IGF1 analogue that binds normally to the IGFR-1 but has little or no affinity for IGF binding proteins) stimulated proliferation in cultured BSC (P < 0.05). Even though EGFR siRNA treatment has no effect on IGFR-1β mRNA expression in cultured BSC, IGFR-1β protein level is substantially reduced in BSC treated with EGFR siRNA. These data suggest that EGFR silencing results in post transcriptional modifications that result in decreased IGFR-1β protein levels. Although it is clear that functional EGFR is necessary for E2 stimulated proliferation of BSC, the role of EGFR is not clear. Transactivation of EGFR may directly stimulate proliferation or EGFR may function to maintain the level of IGFR-1β which is necessary for E2 stimulated proliferation. It also is possible that the role of EGFR in E2-stimulated BSC proliferation may involve both of these mechanisms.

      PubDate: 2014-01-22T07:42:07Z
  • Effect of RU486 and indomethacin on meiotic maturation, formation of
           extracellular matrix and progesterone production by porcine oocyte-cumulus
    • Abstract: Publication date: Available online 21 January 2014
      Source:Domestic Animal Endocrinology
      Author(s): E. Nagyova , S. Scsukova , J. Kalous , A. Mlynarcikova
      This study was designed to determine whether inhibition of either cyclooxygenase-2 (COX-2) by indomethacin or progesterone receptor (PR) by PR antagonist, RU486, affects oocyte maturation, progesterone production and covalent binding between hyaluronan (HA) and heavy chains of inter-alpha trypsin inhibitor (IαI) as well as expression of cumulus expansion-associated proteins (HABP, TNFAIP6, PTX3) in oocyte-cumulus complexes (OCC). The experiments were based on freshly isolated porcine OCC cultures in which the consequences of PR and COX-2 inhibition on the final processes of oocyte maturation were determined. Granulosa cells (GCs) and OCC were cultured in medium supplemented with FSH/LH (both 100 ng/mL) in the presence/absence of RU486 or indomethacin. Western blot analysis, 3H-glucosamine hydrochloride assay, immunofluorescence and radioimmunoassay were performed. Only treatment with RU486 (25 μM) caused a decrease in the number of oocytes reaching germinal vesicle breakdown (GVBD) and metaphase II (M II) stage compared with indomethacin (100 μM) or FSH/LH treatment alone after 44 h. All treated OCC synthesized an almost equal amount of HA. Heavy chains (of IαI)-HA covalent complexes were formed during in vitro FSH/LH-stimulated expansion in RU486- or indomethacin-treated OCC. FSH/LH-induced progesterone production by OCC was increased in the presence of RU486 after 44 h. In contrast, a decrease of FSH/LH-stimulated progesterone production by GCs was detected in the presence of either RU486 or indomethacin after 72 h. We suggest that the PR-dependent pathway may be involved in the regulation of oocyte maturation. Both PR and COX-2 regulate FSH/LH-stimulated progesterone production by OCC and GCs.

      PubDate: 2014-01-22T07:42:07Z
  • Characterization of glucagon-like peptide 2 receptor (GLP2R) gene in
           chickens: functional analysis, tissue distribution, and developmental
           expression profile of GLP2R in embryonic intestine
    • Abstract: Publication date: Available online 18 January 2014
      Source:Domestic Animal Endocrinology
      Author(s): C. Mo , Y. Zhong , Y. Wang , Z. Yan , J. Li
      This study characterized the glucagon-like peptide 2 receptor (GLP2R) gene of chickens because relatively little is known about the underlying mechanism of GLP2 actions in non-mammalian species. Using RT-PCR, we first cloned the chicken GLP2R (cGLP2R) from adult intestine, which was predicted to encode a 529-amino acid receptor precursor. Using a pGL3-CRE luciferase reporter system, we demonstrated that cGLP2R expressed in CHO cells could be potently activated by cGLP2 (EC50, 1.06 nM), but not by its structurally related peptides (EC50, >19 nM), including the newly identified glucagon-like peptide (cGCGL), indicating that cGLP2R is a functional receptor specific to cGLP2. RT-PCR assay revealed that cGLP2R mRNA was widely expressed in adult chicken tissues, including pancreas and various parts of gastrointestinal tract. Using quantitative real-time RT-PCR assays, we further investigated the mRNA expression of cGLP2R and its potential downstream mediators, EGFR ligands (HB-EGF, EREG, and AREG), in the distal duodenum of developing embryos. The mRNA expression levels of GLP2R and EGFR ligands (HB-EGF and AREG) were shown to increase (P, < 0.05 or 0.01) during the late embryonic stages (E16 and E20), implying a potential coordinated action of GLP2 and EGFR ligands on embryonic intestine development. Taken together, our findings not only establish a molecular basis to explore the physiological roles of GLP2 in birds, but also provide comparative insights into the roles of GLP2R and its ligand in vertebrates, such as its roles in embryonic intestine development.

      PubDate: 2014-01-19T04:16:03Z
  • Activation of the CXCL12/CXCR4 signaling axis may drive vascularization of
           the ovine placenta
    • Abstract: Publication date: Available online 7 January 2014
      Source:Domestic Animal Endocrinology
      Author(s): K.E. Quinn , A.K. Ashley , L.P. Reynolds , A.T. Grazul-Bilska , R.L. Ashley
      Early pregnancy, when most embryonic losses occur, is a critical period in which vital placental vascularization is established. Vascular endothelial growth factor (VEGF) is a potent inducer of angiogenesis, and factors regulating VEGF function and/or expression may ultimately affect vascularization. Activation of the C-X-C chemokine receptor type 4 (CXCR4) by its cognate ligand, CXCL12, increases VEGF synthesis and secretion, which in turn stimulates CXCL12 and CXCR4 production and synergistic regulation may influence placental vascularization. We hypothesized that CXCL12, CXCR4, select angiogenic factors and their receptors would increase in placental tissues during early pregnancy and that treatment of ovine trophectoderm (OTR) cells with CXCL12 would increase production of angiogenic factors. To test this hypothesis, maternal caruncle (CAR) and fetal extraembryonic membrane (FM) tissues were collected on days 18, 20, 22, 25, 26 and 30 of pregnancy, and on day 10 of the estrous cycle (control, NP) to determine relative mRNA and/or protein expression of CXCL12 and CXCR4 and selected angiogenic factors. In CAR, expression of mRNA for CXCR4 increased on day 18, 20, 22 and 25 and CXCL12 increased on day 18 and 20 compared to NP ewes. CXCL12 protein followed a similar pattern in CAR tissue, with greater levels on day 20 compared to NP. Greater levels of Fibroblast growth factor two (FGF2) mRNA was observed in CAR on day 20 of gestation compared to day 30. In FM, CXCL12, CXCR4, angiopoietin one (ANGPT1), VEGF, VEGF receptor one (FLT1) were enhanced with advancing pregnancy, whereas FGF2 and kinase insert domain receptor (KDR or VEGF receptor two) peaked on day 25. An increase in protein levels occurred on day 25 compared to day 20 in FM for CXCL12 and CXCR4, as well as a similar tendency for FGF2 protein. Both CXCL12 and CXCR4 are specifically localized to trophoblast cells and to the uterine luminal and glandular epithelium. Treatment of OTR cells with CXCL12 increased mRNA expression for VEGF and FGF2. The relationship between VEGF, FGF2 and the CXCL12/CXCR4 signaling underscores the potential role for this chemokine axis in driving placentation.

      PubDate: 2014-01-10T15:02:41Z
  • Editorial Board
    • Abstract: Publication date: January 2014
      Source:Domestic Animal Endocrinology, Volume 46

      PubDate: 2014-01-10T15:02:41Z
  • Contents
    • Abstract: Publication date: January 2014
      Source:Domestic Animal Endocrinology, Volume 46

      PubDate: 2014-01-10T15:02:41Z
  • Validation of an interferon stimulatory response element reporter gene
           assay for quantifying Type I Interferons
    • Abstract: Publication date: Available online 7 January 2014
      Source:Domestic Animal Endocrinology
      Author(s): S.R. McCoski , M. Xie , E.B. Hall , P.M. Mercadante , T.E. Spencer , P. Lonergan , A.D. Ealy
      The goal of this work was to develop a virus-free, cell-based interferon (IFN) bioassay and determine the utility of this assay on biological samples containing IFN-tau (IFNT), the trophoblast-secreted maternal recognition of pregnancy factor in ruminants. Madin-Darby bovine kidney (MDBK) cells were transduced with lentiviral particles containing a firefly luciferase reporter construct driven by an IFN stimulatory response element (ISRE). Stably transduced cells were selected using puromycin resistance. A linear, dose-responsive response was detected with human IFN-alpha and ovine IFNT. Interferon activity was detected in conditioned media from bovine trophoblast cells and uterine flushes collected from sheep and cattle. Activity also was detected in media collected after individual or small group culture of in vitro-produced bovine blastocysts at d 8 to 10 post-fertilization. In summary, this ISRE-reporter assay may be used as an alternative to virus-dependent, cytopathic assays. It contains a similar sensitivity to interferons and can be completed in a shorter time than cytopathic assays and does not require heightened biosafety conditions after cell transduction.

      PubDate: 2014-01-10T15:02:41Z
  • Central injection of urocortin-3 but not corticotrophin-releasing hormone
           influences the ghrelin/GHS-R1a system of the proventriculus and brain in
    • Abstract: Publication date: Available online 3 January 2014
      Source:Domestic Animal Endocrinology
      Author(s): M.S.I. Khan , H. Kaiya , T. Tachibana
      Ghrelin, the endogenous ligand for growth hormone secretagogue receptor 1a (GHS-R1a), stimulates food intake in mammals centrally and peripherally. In contrast, central injection of ghrelin inhibits feeding in neonatal chicks (Gallus gallus), which is thought to be mediated by the corticotrophin-releasing hormone (CRH) system, indicating that the mechanisms underlying ghrelin’s action are different in chicks and mammals. However, the interaction between the ghrelin system and the CRH system has not been fully clarified in chicks. In the present study, we examined the effect of intracerebroventricular (ICV) injection of CRH and urocortin-3 (UCN-3), a CRH family peptide and an endogenous ligand for the CRH type-2 receptor (CRH-R2), on synthesis and secretion of ghrelin in chicks. ICV injection of UCN-3 but not CRH increased plasma ghrelin concentration (P < 0.05), diencephalic mRNA expression of ghrelin and GHS-R1a (P < 0.05), and tended to decrease ghrelin (P = 0.08) and GHS-R1a (P = 0.10) mRNA expression in the proventriculus. Moreover, ICV injection of UCN-3 tended to increase diencephalic mRNA expression of CRH-R2 (P = 0.08) while CRH had no effect on it. In addition, ICV injection of CRH but not UCN-3 increased plasma corticosterone concentration (P < 0.05) and decreased the diencephalic mRNA expression of CRH-R1 (P < 0.05). These results clearly indicate that the roles of the CRH system for the ghrelin system are divided. The present study suggests that UCN-3 is mainly involved in the ghrelin system in chicks perhaps through the CRH-R2.

      PubDate: 2014-01-07T00:25:00Z
  • Calcium extrusion regulatory molecules: differential expression during
           pregnancy in the porcine uterus
    • Abstract: Publication date: Available online 3 January 2014
      Source:Domestic Animal Endocrinology
      Author(s): Y. Choi , H. Seo , J. Shim , I. Yoo , H. Ka
      Calcium ions in the uterine endometrium are essential for the establishment and maintenance of pregnancy, but the cellular and molecular mechanisms of calcium ion regulation in the endometrium are not fully understood. Our previous study in pigs demonstrated that calcium regulatory molecules, transient receptor potential, vanilloid type 6 (TRPV6) and calbindin-D9K (S100G) are expressed in the uterine endometrium during the estrous cycle and pregnancy. However, we did not determine the expression of calcium extrusion regulatory molecules, plasma membrane calcium ATPases (ATP2Bs), sodium/calcium exchangers (SLC8As), or potassium-dependent sodium/calcium exchangers (SLC24As) in the uterine endometrium and conceptuses. Thus, in this study we determine whether ATP2Bs, SCL8As, and SLC24As are expressed in the uterine endometrium during the estrous cycle and pregnancy and in conceptuses during early pregnancy. Real-time RT-PCR analysis showed that ATP2Bs, SLC8As, and SLC24As were expressed in the uterine endometrium in a pregnancy status- and stage-specific manner. Conceptuses during early pregnancy also expressed these molecules. In situ hybridization analysis showed that ATP2B1, SLC8A1, and SLC24A4 were localized mainly to luminal and glandular epithelium and stromal cells in the endometrium during pregnancy. These results indicate that calcium extrusion regulatory molecules are expressed in the uterine endometrium during the estrous cycle and pregnancy and in conceptuses during early pregnancy, indicating that calcium extrusion regulatory molecules may play important roles in the establishment and maintenance of pregnancy by regulating calcium ion concentration in the uterine endometrium in pigs.

      PubDate: 2014-01-03T12:27:56Z
  • Lactation driven dynamics of adiponectin supply from different fat depots
           to circulation in cows
    • Abstract: Publication date: Available online 25 December 2013
      Source:Domestic Animal Endocrinology
      Author(s): S.P. Singh , S. Häussler , J.F.L. Heinz , S.H. Akter , B. Saremi , U. Müller , J. Rehage , S. Dänicke , M. Mielenz , H. Sauerwein
      Adipose tissue (AT) depots are heterogeneous in terms of morphology and adipocyte metabolism. Adiponectin, one of the most abundant adipokines, is known for its insulin sensitising effects and its role in glucose and lipid metabolism. Very little is known about the presence of adiponectin protein in visceral (vc) and subcutaneous (sc) AT depots. We assessed serum adiponectin and adiponectin protein concentrations and the molecular weight forms in vc (mesenterial, omental and retroperitoneal) and sc (sternum, tail-head and withers) AT of primiparous dairy cows during early lactation. Primiparous German Holstein cows (n = 25) were divided into a control (CON) and a conjugated linoleic acid (CLA) group. From day 1 of lactation until slaughter, CLA cows were fed 100 g of a CLA supplement/d (about 6% of cis-9, trans-11 and trans-10, cis-12 isomers each), whereas the CON cows received 100 g of a fatty acid mixture/d instead of CLA. Blood samples from all animals were collected from 3 wk before calving until slaughter on day 1 (n = 5, CON cows), 42 (n = 5 each of CON and CLA cows) and 105 (n = 5 each of CON and CLA cows) of lactation when samples from different AT depots were obtained. Adiponectin was measured in serum and tissue by ELISA. In all AT depots adiponectin concentrations were lowest on day 1 compared to day 42 and day 105, and circulating adiponectin reached a nadir around parturition. Retroperitoneal AT had the lowest adiponectin concentrations, however, when taking total depot mass into consideration, the portion of circulating adiponectin was higher in vc than sc AT. Serum adiponectin was positively correlated with adiponectin protein concentrations but not with the mRNA abundance in all fat depots. The CLA supplementation did not affect adiponectin concentrations in AT depots. Furthermore, inverse associations between circulating adiponectin and measures of body condition (empty body weight, back fat thickness and vc AT mass) were observed. In all AT depots at each time, adiponectin was present as high (about 300 kDa) and medium (about 150 kDa) molecular weight complexes similar to that of the blood serum. These data suggest differential contribution of AT depots to circulating adiponectin.

      PubDate: 2013-12-28T04:35:11Z
  • Effect of premilking stimulation and milking frequency on milking-induced
           prolactin release in lactating dairy cows
    • Abstract: Publication date: Available online 6 December 2013
      Source:Domestic Animal Endocrinology
      Author(s): P. Lacasse , S. Ollier
      Four experiments were conducted to investigate the factors controlling prolactin (PRL) release at milking. Each experiment used nine dairy cows in mid-lactation in a 3 × 3 Latin square design. Experiment 1 evaluated the effect of premilking stimulation. The milking unit was attached after 0, 20, or 120 s of manual stimulation. Blood samples were collected from 20 min prior to 60 min after milking-unit attachment. The peak value and total PRL release (area under the curve) were not affected by the treatments, but the 120s stimulation hastened PRL release. Stimulation (20 or 120 s) increased the βendorphin peak value (P = 0.02), but the magnitudes of PRL and βendorphin releases were not correlated. Experiment 2 evaluated the effect of milking frequency. Cows were milked twice, at 7:00 and 19:00; three times, at 7:00, 13:00, and 19:00; or seven times, at 7:00, 9:00, 11:00, 13:00, 15:00, 17:00, and 19:00. The amount of PRL released at the 19:00 milking decreased as the number of milkings increased (P < 0.01), and peak values were smaller with seven milkings than with two and three (P < 0.05). Beta-endorphin release was not affected by milking frequency and not correlated with the magnitude of PRL release. Experiment 3 evaluated the effect of manual stimulation between milkings on milking-induced PRL release. Cows received no stimulation; five stimulations (5 min each), at 9:00, 11:00, 13:00, 15:00, and 17:00; or one stimulation at 17:00. Manual stimulation reduced (P < 0.5) the amount of PRL released and the maximum PRL concentration at the 19:00 milking, but there was no difference between one and five stimulations. Manual stimulation did not affect the amount of cortisol released but did impair milk ejection. Experiment 4 evaluated the effect of milking frequency on the PRL release induced by manual stimulation. Cows were milked at 7:00 only; at 7:00, 9:00, 11:00, 13:00, 15:00, and 17:00; or at 7:00 and 17:00. All cows then received manual stimulation at 19:00. Milking every 2 h or once 2 h prior to manual stimulation reduced the amount of PRL released and the maximum PRL concentration but did not affect cortisol release. In conclusion, the length of premilking stimulation has no significant impact on milking-induced PRL release, but increasing milking frequency reduces the amount of PRL released at milking. This effect is due not to the number of milkings or the amount of milk harvested during the milking but to the interval since the preceding milking.

      PubDate: 2013-12-09T07:20:20Z
  • Obesity and sex influence insulin resistance and total and multimer
           adiponectin levels in adult neutered domestic shorthaired client-owned
    • Abstract: Publication date: Available online 5 December 2013
      Source:Domestic Animal Endocrinology
      Author(s): C.R. Bjornvad , J.S. Rand , H.Y. Tan , K.S. Jensen , F.J. Rose , P.J. Armstrong , J.P. Whitehead
      In this study, we estimated insulin sensitivity and determined plasma concentrations of total-, low-molecular weight (LMW) and high-molecular weight (HMW)-adiponectin and leptin in 72 domestic short-haired, neutered, client-owned cats. Glucose tolerance was assessed with an intravenous glucose tolerance test and body fat percentage (BF%) was measured using Dual-energy X-ray absorptiometry. Total adiponectin was measured using two different ELISA´s. Low-molecular weight and HMW adiponectin plasma concentrations were determined by Western blotting after sucrose-gradient velocity centrifugation and the adiponectin multimer ratio (SA=HMW/(HMW+LMW)) was calculated. Differences in glucose tolerance, leptin, total adiponectin and multimer ratio among lean (BF%<35, n=26) overweight (35<BF%<45, n=28) and obese cats (BF%>45, n=18) as well as between male (n=34) and female (n=38) neutered cats were evaluated by linear regression and two way ANOVA. Sex and age were included as covariates for analysis of BF% while BF%, fat mass and lean body mass were covariates for analysis of sex differences. Increased BF% was negatively correlated with multimer ratio (SA, r = -45; P < 0.002), while there were no differences in total adiponectin concentrations among BF% groups (P > 0.01). Male cats had indices of decreased insulin tolerance and significantly lower total adiponectin concentrations compared with female cats (mean ± SEM, 3.7 ± 0.4 vs 5.4 ± 0.5 μg/mL, P < 0.02). Altered adiponectin multimer ratios could contribute to an obesity-associated decreasing glucose tolerance in cats and low total adiponectin concentrations may relate to increased risk of diabetes mellitus in neutered male cats.

      PubDate: 2013-12-05T10:06:20Z
  • Differential expression of hypothalamic fear- and stress-related genes in
           broiler chickens showing short or long tonic immobility
    • Abstract: Publication date: Available online 27 November 2013
      Source:Domestic Animal Endocrinology
      Author(s): S. Wang , Y. Ni , F. Guo , Z. Sun , A. Ahmed , R. Zhao
      The serotonin system and the hypothalamic-pituitary-adrenal (HPA) axis play important roles in modulating fear and stress-coping characteristics. Tonic immobility (TI) is a fear-related phenotype and previously we have shown that broiler chickens showing short TI duration demonstrate better growth performance and higher adaptability to stress. Here we sought to further elucidate the central mechanisms underlying the phenotypic differences between chickens showing short and long TI duration (STI and LTI), by comparing the hypothalamic expression of genes in the serotonergic system and the HPA axis under basal and corticosterone (CORT)-exposed situations. The STI broilers demonstrated significantly lower (P < 0.01) hypothalamic expression of serotonin reuptake transporter and serotonin receptor 1A. Moreover, 11β-hydroxysteroid dehydrogenase type 2 (HSD2) was expressed significantly lower in STI chickens at the level of both mRNA (P < 0.01) and protein (P < 0.05). Hypothalamic expression of glucocorticoid receptor (GR) mRNA tended to be higher (P < 0.059) in LTI chickens, but the protein content was approximately 2 times higher (P < 0.01) in STI chickens. The uncoupled expression of GR mRNA and protein was associated with significantly lower (P < 0.05) expression of gga-miR-181a, gga-miR-211 and gga-miR-22, which are predicted to target GR, in STI chickens. Corticosterone administration reduced the mRNA expression of postsynaptic serotonin receptors, 5HT1B (P = 0.059) and 5HT7 (P < 0.05), yet significantly increased the protein content of HSD2 (P < 0.05). These results suggest that broilers of different TI phenotypes demonstrate distinct pattern of hypothalamic expression of fear- and stress-related genes.

      PubDate: 2013-11-28T02:12:06Z
  • Insulin infusion stimulates whole-body protein synthesis and activates the
           upstream and downstream effectors of mTOR signaling in the gluteus medius
           muscle of mature horses
    • Abstract: Publication date: Available online 20 November 2013
      Source:Domestic Animal Endocrinology
      Author(s): Kristine L. Urschel , Jeffery Escobar , L. Jill McCutcheon , Raymond J. Geor
      Little is known about the role insulin plays in regulating whole-body and muscle protein metabolism in horses. The objective of this study was to determine the effects of graded rates of insulin infusion on plasma amino acid concentrations and the activation of factors in the mTOR signaling pathway in the skeletal muscle of horses. Isoglycemic, hyperinsulinemic clamp procedures were conducted in 8 mature, Thoroughbred mares receiving four rates of insulin infusion: 0 mU/kg/min (CON), 1.2 mU/kg/min (LOWINS), 3 mU/kg/min (MEDINS) and 6 mU/kg/min (HIGHINS). Blood samples were taken throughout the clamp procedures to measure plasma amino acid concentrations, and a biopsy from the gluteus medius muscle was collected at the end of the 2 h clamp to measure phosphorylation of protein kinase B (Akt), eukaryotic initiation factor 4E-binding protein 1 (4E-BP1), and riboprotein S6 (rpS6). Plasma concentrations of most of the essential amino acids decreased (P < 0.05) after 120 min of insulin infusion in horses receiving the LOWINS, MEDINS and HIGHINS treatments, with the largest decreases occurring in horses receiving the MEDINS and HIGH INS treatments. Phosphorylation of Akt, 4E-BP1 and rpS6 increased with all three rates of insulin infusion (P > 0.05), relative to CON, with maximum phosphorylation achieved with MEDINS and HIGHINS treatments. These results indicate that insulin stimulates whole-body and muscle protein synthesis in mature horses.

      PubDate: 2013-11-23T16:31:48Z
  • Effects of the rate of insulin infusion during isoglycemic,
           hyperinsulinemic clamp procedures on measures of insulin action in
           healthy, mature Thoroughbred mares
    • Abstract: Publication date: Available online 20 November 2013
      Source:Domestic Animal Endocrinology
      Author(s): Kristine L. Urschel , Jeffery Escobar , L. Jill McCutcheon , Raymond J. Geor
      The objective of this study was to determine whether the rate of insulin infusion during isoglycemic hyperinsulinemic clamp procedures affected measures of insulin action, including glucose disposal and plasma NEFA, endothelin-1 (ET-1) and nitric oxide concentrations, in mature, healthy horses. Eight Thoroughbred mares were studied during a 2 h hyperinsulinemic clamp procedure, conducted at each of four rates of insulin infusion: 0 (CON), 1.2 (LOWINS), 3 (MEDINS) and 6 (HIGHINS) mU/kg/min. The infusion rate of a dextrose solution was adjusted throughout the clamp procedures to maintain blood glucose levels within 10% of baseline glucose concentrations. Plasma insulin concentrations (I) were measured throughout the clamp procedures, and used with the rate of glucose infusion (M) to calculate the M/I ratio, a measure of insulin action on glucose disposal. The rate of glucose infusion increased with rate of insulin infusion (P < 0.05). The M/I ratio was highest for the LOWINS treatment (P < 0.05), and decreased by 62% (P < 0.05) and 84% (P < 0.05) for the MEDINS and HIGHINS treatments, respectively. While plasma NEFA concentrations were lower than baseline by t = 30 min of the clamp procedures in the LOWINS, MEDINS and HIGHINS treatments (P < 0.05), the decline was similar for all three rates of insulin infusion. Jugular vein plasma nitric oxide and ET-1 concentrations were not affected by insulin infusion rate (P > 0.05). The data indicate that it is important to standardize insulin infusion rate if data are to be compared between hyperinsulinemic clamp studies.

      PubDate: 2013-11-23T16:31:48Z
  • Expression of angiogenesis-related genes in canine cortisol-secreting
           adrenocortical tumors
    • Abstract: Publication date: Available online 16 November 2013
      Source:Domestic Animal Endocrinology
      Author(s): M.M.J. Kool , S. Galac , H.S. Kooistra , J.A. Mol
      The aim of this study was to evaluate the expression of angiogenesis-related genes in canine cortisol-secreting adrenocortical tumors (ATs). Quantitative RT-PCR analysis revealed mRNA encoding for vascular endothelial growth factor (VEGF), VEGF-receptors 1 and 2, angiopoietin 1 and 2 (ANGPT1 and ANGPT2), the splice variant ANGPT2 443 , the ANGPT-receptor Tie2, and basic fibroblast growth factor (bFGF) in 38 canine cortisol-secreting ATs (26 carcinomas and 12 adenomas) and 15 normal adrenals. The relative expression of both ANGPT2 and ANGPT2 443 was higher in adenomas (P = 0.020 for ANGPT2 and P = 0.002 for ANGPT2443) and carcinomas (P = 0.003 for ANGPT2 and P < 0.001 for ANGPT2443) compared to normal adrenals, and this enhanced expression was also detected using Western blot. Immunohistochemistry demonstrated expression of ANGPT2 protein in AT cells and in vascular endothelial cells of carcinomas, while Tie2 was mainly present in the tumor vascular endothelial cells. The ANGPT2/ANGTPT1 ratio, a marker for a pro-angiogenic state, was higher in both adenomas (P = 0.020) and carcinomas (P = 0.043). Using the human H295R cortisol-producing adrenocortical carcinoma cell line, we were able to demonstrate that the ANGPT2 expression was stimulated by cAMP and progesterone, but not by cortisol. In conclusion, canine cortisol-secreting ATs have enhanced ANGPT2 expression with a concomitant shift towards a pro-angiogenic state. Based on this information, treatment modalities may be developed that interfere with ANGPT2 expression, including inhibition of the cAMP/PKA pathway, or of the effect of ANGPT2, by using specific ANGPT2 inhibitors.

      PubDate: 2013-11-19T23:09:35Z
  • Breed differences in insulin sensitivity and insulinaemic responses to
           oral glucose in horses and ponies of moderate body condition score
    • Abstract: Publication date: Available online 9 November 2013
      Source:Domestic Animal Endocrinology
      Author(s): N.J. Bamford , S.J. Potter , P.A. Harris , S.R. Bailey
      There may be breed-related differences in the innate insulin sensitivity (SI) of horses and ponies, an important factor believed to be associated with the risk of laminitis. The aim of this study was to measure the glucose and insulin responses of different breeds of horses and ponies in moderate body condition to a glucose-containing meal, and to compare these responses with the indices of SI as determined by a frequently-sampled intravenous glucose tolerance test (FSIGT). Eight Standardbred horses, eight mixed-breed ponies and seven Andalusian-cross horses with a mean (± SEM) body condition score 5.0 ± 0.3 out of 9 were used in this study. Each animal underwent an oral glucose tolerance test (OGTT) in which they were fed a fibre-based ration (2.0 g/kg BW) containing 1.5 g/kg BW added glucose, as well as a standard FSIGT with minimal model analysis. The glucose response variables from the OGTT were similar between groups; however, the peak insulin concentration was higher in ponies (94.1 ± 29.1 μIU/mL; P = 0.003) and Andalusians (85.3 ± 18.6; P = 0.004) when compared with Standardbreds (21.2 ± 3.5). The insulin area under the curve was also higher in ponies (13.5 ± 3.6 IU·min·L-1; P = 0.009) and Andalusians (15.0 ± 2.7; P = 0.004) when compared with Standardbreds (3.1 ± 0.6). Insulin sensitivity, as determined by the FSIGT, was lower in Andalusians (0.99 ± 0.18 x 10-4/[mIU·min]) compared with Standardbreds (5.43 ± 0.94; P < 0.001), and in ponies (2.12 ± 0.44; P = 0.003) compared with Standardbreds. Peak insulin concentrations from the OGTT were negatively correlated with SI (P < 0.001; rs = -0.75). These results indicate that there are clear breed-related differences in the insulin responses of horses and ponies to oral and intravenous glucose. All animals were in moderate body condition, indicating that breed-related differences in insulin dynamics occurred independent of obesity.

      PubDate: 2013-11-11T13:08:46Z
  • Identification and characterization of the free fatty acid receptor 2
           (FFA2) and a novel functional FFA2-like receptor (FFA2L) for short-chain
           fatty acids in pigs: evidence for the existence of a duplicated FFA2 gene
           (FFA2L) in some mammalian species
    • Abstract: Publication date: Available online 1 November 2013
      Source:Domestic Animal Endocrinology
      Author(s): J. Zhang , S. Cheng , Y. Wang , X. Yu , J. Li
      Free fatty acid receptor 2 (FFA2, also called GPR43) is reported to play a critical role in mediating the actions of short-chain fatty acids (SCFAs) in humans and mice. However, little is known about the structure, functionality, and tissue expression of FFA2 in other mammalian species including pigs. In present study, the full-length cDNAs of FFA2 (pFFA2) and a novel FFA2-like gene (named pFFA2L) were cloned from pig intestines by RT-PCR. Both cloned pFFA2 and pFFA2L are predicted to encode two receptors of remarkable structural similarity and share high amino acid sequence identities with FFA2 from other mammalian species. Interestingly, the novel FFA2L could also be identified in other 9 mammalian species, suggesting that FFA2L was likely duplicated from FFA2 in the last common ancestor of these species. Using a pGL4-SRE-luciferase reporter assay, we demonstrated that pFFA2 expressed in HEK293 cells could be activated by acetate, propionate, and butyrate equipotently, while pFFA2L could be activated only by acetate and propionate, indicating that both pFFA2 and pFFA2L are functional receptors for SCFAs with non-identical pharmacological properties. RT-PCR revealed that pFFA2 mRNA was widely expressed in nearly all tissues examined including adipose tissue and gastrointestinal (GI) tract, whereas pFFA2L expression was mainly restricted to GI tract. Taken together, our findings raise a novel concept that the actions of SCFAs are likely mediated by two FFA2 (FFA2 and FFA2L) in target tissues of some mammalian species, such as the GI tract of pigs.

      PubDate: 2013-11-03T18:01:09Z
  • Determination of anti-Müllerian hormone at estrus during a
           synchronized and a natural bovine estrous cycle
    • Abstract: Publication date: Available online 27 October 2013
      Source:Domestic Animal Endocrinology
      Author(s): K.E. Pfeiffer , L.J. Jury , J.E. Larson
      Anti-Müllerian hormone (AMH) has been correlated with phenotypic indicators of fertility. However, the effects of exogenous hormones used during estrus synchronization on AMH have not been evaluated. Therefore, the objective of this experiment was to determine whether concentrations of AMH at estrus are similar between a synchronized compared with a natural estrous cycle. Nulliparous dairy and beef heifers (n = 68) were synchronized with the Select Synch + controlled internal drug release (CIDR) protocol (GnRH + CIDR-7 d-CIDR removal + PG). Heifers were observed for expression of estrus every 6 h until 84 h after the injection of PG. Visual detection of the subsequent estrus, considered natural estrus, occurred every 6 h from day 16 to 24 after synchronized estrus. At the time of standing estrus, ovarian structures in heifers were evaluated by transrectal ultrasonography. Blood samples were collected at estrus for analysis of concentrations of AMH during the synchronized and natural estrous cycles. The GLM and CORR procedures of SAS were used to analyze data. Concentrations of AMH between natural and synchronized estrus were positively correlated (r = 0.67; P < 0.001). Mean concentration of AMH did not differ (P > 0.05) between the natural (0.0543 ± 0.0076 ng/mL) or synchronized (0.0428 ± 0.0076 ng/mL) estrous cycles. In conclusion, concentrations of AMH were similar between natural and synchronized estrous cycles. Concentrations of AMH in natural and synchronized estrous cycles were highly correlated within individual heifers and varied among heifers with beef heifers having increased (P < 0.05) concentrations of AMH compared with dairy heifers (0.0638 ± 0.01 and 0.0402 ± 0.01 ng/mL, respectively).

      PubDate: 2013-10-31T02:38:17Z
  • Editorial Board
    • Abstract: Publication date: November 2013
      Source:Domestic Animal Endocrinology, Volume 45, Issue 4

      PubDate: 2013-10-26T13:24:42Z
  • Contents
    • Abstract: Publication date: November 2013
      Source:Domestic Animal Endocrinology, Volume 45, Issue 4

      PubDate: 2013-10-26T13:24:42Z
  • Saliva collection by using filter paper for measuring cortisol levels in
    • Abstract: Publication date: Available online 11 October 2013
      Source:Domestic Animal Endocrinology
      Author(s): D. Oyama , M. Hyodo , H. Doi , T. Kurachi , M. Takata , S. Koyama , T. Satoh , G. Watanabe
      Four experiments were conducted to evaluate the accuracy and reliability of noninvasive evaluation of cortisol in saliva of dogs. In experiment 1, we measured the cortisol concentration in the filter paper on which 250-μL cortisol solutions had been quantitatively pipetted and in filter papers dipped in cortisol solution. In experiment 2, we collected the blood and saliva of dogs 3 times at 30-min intervals and compared the cortisol concentrations to examine whether the dynamics of cortisol in the blood and saliva are similar. The results of experiments 1 and 2 showed that the cortisol concentration can be quantitatively measured with this method and that the dynamics of cortisol concentration in the plasma and saliva collected by using filter paper are not different (P = 0.14 for experiment 1 and P = 0.51 for experiment 2). In experiment 3, to investigate the factors related to inducing stress in dogs by using the filter-paper method of collecting saliva, we compared the cortisol concentrations at 0 and 30 min after collecting the saliva of pet dogs. The dog owners completed a survey on their dogs, providing basic information and reporting the collection of their dog's saliva. We found that the cortisol concentrations increased significantly in dogs whose owners spent >2 min collecting saliva (P = 0.005), suggesting that prompt collection of saliva is necessary for accurate assessment of cortisol without induction of a stress response. In addition, the cortisol concentrations increased significantly in dogs whose teeth were not regularly brushed (P = 0.04), suggesting that regular teeth brushing mitigates the effect of the collection process on cortisol concentrations in the saliva, with minimal stress to the dogs. In experiment 4, we measured cortisol concentrations in pet dogs accustomed to having their teeth brushed by their owners, before and after interaction with their owners, to assess whether brushing induces stress in dogs. We detected that the cortisol concentrations significantly decreased after human–dog interaction (P = 0.008), suggesting that this method does not induce stress in dogs. Our study indicates that the method of saliva collection by using filter paper is effective in measuring the cortisol concentrations to evaluate stress, although certain steps are required to enhance accuracy.

      PubDate: 2013-10-15T11:20:03Z
  • Oral administration of melatonin counteracts several of the effects of
           chronic stress in rainbow trout
    • Abstract: Publication date: Available online 12 October 2013
      Source:Domestic Animal Endocrinology
      Author(s): M. Conde-Sieira , J.L.P. Muñoz , M.A. López-Patiño , M. Gesto , J.L. Soengas , J.M. Míguez
      To assess a possible anti-stress role of melatonin in fish, we orally administered melatonin to rainbow trout for 10 d, and then kept the fish under normal or high stocking density conditions during the last 4 d. Food intake, biochemical parameters in plasma (cortisol, glucose and lactate concentrations), liver (glucose and glycogen concentrations, and glycogen synthase activity), enzyme activities of amylase, lipase, and protease in foregut and midgut, and content of the hypothalamic neurotransmitters dopamine (DA) and serotonin (5HT), as well as their oxidized metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and 5-hydroxy-3-indoleacetic acid (5HIAA), were evaluated under those conditions. High stocking density conditions alone induced changes indicative of stress conditions in plasma cortisol concentrations, liver glycogenolytic potential, the activities of some digestive enzymes, and the DOPAC/DA and 5HIAA/5HT ratios in hypothalamus. Melatonin treatment in non-stressed fish induced an increase in liver glycogenolytic potential, increased the activity of some digestive enzymes, and enhanced serotoninergic and dopaminergic metabolism in hypothalamus. The presence of melatonin in stressed fish resulted in a significant interaction with cortisol concentrations in plasma, glycogen content and glycogen synthase activity in liver, and dopaminergic and serotoninergic metabolism in hypothalamus. In general, the presence of melatonin mitigated several of the effects induced by stress supporting an anti-stress role for melatonin in rainbow trout.

      PubDate: 2013-10-15T11:20:03Z
  • Circannual body reserve dynamics and metabolic profile changes in Romane
           ewes grazing on rangelands
    • Abstract: Publication date: Available online 14 October 2013
      Source:Domestic Animal Endocrinology
      Author(s): E. González-García , V. Gozzo de Figuereido , D. Foulquie , E. Jousserand , P. Autran , S. Camous , A. Tesniere , F. Bocquier , M. Jouven
      Throughout an entire year, forty-one Romane ewes reared in an extensive rangeland were used to investigate temporal changes in body reserves (BR) and profiles of related metabolites and metabolic hormones. Ewes were allocated to homogeneous groups according to BW and BCS, and distributed by parity [primiparous (PRIM), n = 21; multiparous (MULT), n = 20] and litter size (LSi) [lambing singletons (SING), n = 21 or TWINS, n = 20]. The feeding system was based on rotational grazing of rangeland paddocks and progressive supplementation with hay, silage and barley at late pregnancy during the winter. Individual BW, BCS, plasma NEFA, β-hydroxybutyrate (ß-OHB), glucose, insulin, leptin and triiodothyronine (T3) were monitored at -56, -12, 8, 49, 76, 107, 156, 195, 216, 246 and 301 days relative to lambing. The BR mobilization was observed from late pregnancy to the end of suckling and varied as a function of the ewe energy balance but also due to transitions from fertilized to ‘native’ rangeland paddocks and by supplementation. Contrarily, BR accretion occurred from weaning, during the dry-off and until the start of the next pregnancy. Lipolysis was well reflected by NEFA, ß-OHB and T3 kinetics. Mean BW (but not mean BCS) was affected by parity (MULT > PRIM), whereas both BW and BCS were influenced by LSi (SING > TWINS), but only for MULT. The most drastic BW loss was observed during the mid-suckling period (49 DIM) in all ewes. The lack of effects of LSi in PRIM but not in MULT was also evident in the majority of blood plasma kinetics, which were affected (P < 0.0001) by physiological stage in all ewes. A tendency to ketosis (β-OHB) was found in ewes nursing TWINS around lambing irrespective of parity. Glucose concentrations were greater during suckling and dry-off, and a peak (0.96 ± 0.05 g/L) was attained at 156 DIM in MULT nursing TWINS. The highest plasma leptin concentration was observed during the start and the middle of the next pregnancy in MULT (107-216 DIM; 9.6 ± 0.44 ng/mL). In all ewes the physiological stage affected T3, which was affected by LSi just in MULT (from late pregnancy, MULT×SING > MULT×TWINS; 99.91 vs. 85.52 ng/dL) and during suckling (111.7 ± 4.18 ng/dL). Lamb BW was affected at birth and weaning by parity (MULT > PRIM) and LSi (SING > TWINS). Overall, temporal changes in BR were directly affected by the transition of physiological states and feeding levels, while individual responses were predetermined by parity. In MULT, the reactivity and magnitude of response was influenced by LSi. The whole set of parameters allowed us to detect sensitive and critical periods throughout the entire annual cycle. We thus identified opportunities for improved nutritional management, for example during physiological states usually underestimated like early and mid-pregnancy. This work demonstrates the applicability of long-term studies about BR dynamics in ruminants as a potential component contributing to farm economic resilience.

      PubDate: 2013-10-15T11:20:03Z
  • Global proteomic characterisation of uterine histotroph recovered from
           beef heifers yielding good quality and degenerate Day 7 embryos
    • Abstract: Publication date: Available online 14 October 2013
      Source:Domestic Animal Endocrinology
      Author(s): M.E. Beltman , M.P. Mullen , G. Elia , M. Hilliard , M.G. Diskin , A.C.O. Evans , M.A. Crowe
      The objective was to analyse the proteomic composition of uterine flushes collected from beef heifers on Day 7 post-insemination. Oestrus was synchronised in cross-bred beef heifers using a Controlled Intravaginal Drug Releasing device (CIDR) protocol. Heifers detected in standing oestrus (within 24-48 h post CIDR removal) were inseminated (oestrus=Day 0) with frozen-thawed semen from a single ejaculate of a bull with proven fertility. Heifers from which an embryo was recovered (following slaughter on Day 7) were classified as either having a viable embryo (morula/blastocyst stage) or a degenerate embryo (arrested at the 2- to 16-cell stage). The overall recovery rate (viable and degenerate combined) was 64%. Global LC-MS/MS proteomic analysis of the histotroph collected identified 40 high confidence proteins present on Day 7; 26 proteins in the viable group, 10 in the degenerate group and four shared between both groups. Five proteins (Platelet-activating factor acetylhydrolase IB subunit gamma (PAFAH1B3), Tubulin alpha-1D chain, Tubulin beta-4A chain, Cytochrome C and Dihydropyrimidinase-related protein-2) were unique or more abundant in the histotroph collected from animals with a viable embryo and one protein (S100A4) was more abundant in the histotroph collected from animals with a degenerate embryo. Of interest, PAFAH1B3, detected only in histotroph from the group yielding viable embryos, belongs to the group of platelet activating factors that are known to be important for the development of the pre-implantation embryo in other species. To our knowledge this is the first report of PAFAH1B3 in relation to bovine early embryonic development.

      PubDate: 2013-10-15T11:20:03Z
  • Effects of leptin and adiponectin on the growth of porcine myoblasts are
           associated with changes in p44/42 MAPK signaling
    • Abstract: Publication date: Available online 10 October 2013
      Source:Domestic Animal Endocrinology
      Author(s): K. Will , J. Kuzinski , C. Kalbe , M.F. Palin , C. Rehfeldt
      We hypothesized that both adiponectin and leptin affect the growth of porcine skeletal muscle cells, with fatty acids acting as modifiers in adipokine action and that both adipokines influence the gene expression of their receptors. Therefore, the objective of this study was to investigate the effects of recombinant adiponectin and leptin on cell number (DNA) and DNA synthesis rate with and without oleic acid supplementation, on cell death, and on key intracellular signaling molecules of proliferating porcine myoblasts in vitro. Moreover, the mRNA expression of genes encoding for the leptin and adiponectin receptors (LEPR, ADIPOR1, ADIPOR2) as affected by leptin or adiponectin was examined. Recombinant porcine adiponectin (40 μg/mL) and leptin (20 ng/mL) increased DNA synthesis rate, measured as [3H]-thymidine incorporation (P < 0.01), reduced cell viability in terms of lactate dehydrogenase release (P < 0.05), or lowered DNA content after 24 h (P < 0.05). In adiponectin-treated cultures, oleic acid supplementation increased DNA synthesis rate and reduced cell number in a dose-dependent manner (P < 0.05). Both adiponectin (P = 0.07) and leptin (P < 0.05) induced a transient activation of p44/42 mitogen-activated protein kinase (p44/42 MAPK; ERK 1/2) after 15 min, followed by decreases after 60 and 180 min (P < 0.05). Adiponectin tended to increase c-fos activation (P = 0.08) and decreased p53 activation at 180 min (P = 0.03). Both adiponectin and leptin down-regulated the abundance of ADIPOR2 mRNA and, transiently, of LEPR mRNA (P < 0.05). In conclusion, adiponectin and leptin may adversely affect the growth of porcine myoblasts, which is related to p44/42 MAPK signaling and associated with changes in ligand receptor gene expression.

      PubDate: 2013-10-11T21:23:09Z
  • Enteral leptin administration affects intestinal autophagy in suckling
    • Abstract: Publication date: Available online 7 October 2013
      Source:Domestic Animal Endocrinology
      Author(s): M. Słupecka , J. Woliński , M. Gajewska , S.G. Pierzynowski
      Leptin has been shown to play an integral role in the endocrine regulation of metabolism. Moreover, a substantial amount of this peptide has been found in colostrum and milk. The aim of the study was to investigate the effects of exogenous leptin, administered intragastrically, on the process of autophagy and the changes in cell hyperplasia and hypertrophy in the small intestine mucosa. Three groups (n = 6) of neonatal piglets were used in the study. The pigs were fed either by their sows (sow-reared piglets) or with only milk formula, or with milk formula together with leptin administered via a stomach tube (10 μg/kg BW) every 8 h for 6 d. We have shown that pure milk formula feeding significantly elevates (P < 0.05) autophagy compared with that observed in sow-reared piglets. Compared with the control group, feeding milk formula supplemented with leptin resulted in a significant decrease (P < 0.05) in immunodetection of microtubule-associated protein 1 light chain 3, as well as significantly accelerated epithelial cell renewal (P < 0.05). We demonstrated that autophagy is involved in the remodeling of the small intestine mucosa and that leptin, when administered enterally, may be an important factor for its regulation.

      PubDate: 2013-10-08T06:18:13Z
  • Dietary selenium and nutritional plane alter specific aspects of maternal
           endocrine status during pregnancy and lactation
    • Abstract: Publication date: Available online 2 October 2013
      Source:Domestic Animal Endocrinology
      Author(s): C.O. Lemley , A.M. Meyer , T.L. Neville , D.M. Hallford , L.E. Camacho , K.R. Maddock-Carlin , T.A. Wilmoth , M.E. Wilson , G.A. Perry , D.A. Redmer , L.P. Reynolds , J.S. Caton , K.A. Vonnahme
      Objectives were to examine effects of selenium (Se) supply and maternal nutritional plane during gestation on placental size at term and maternal endocrine profiles throughout gestation and early lactation. Ewe lambs (n = 84) were allocated to treatments that included Se supply of adequate Se (ASe, 11.5 μg/kg BW) or high Se (HSe, 77 μg/kg BW) initiated at breeding and nutritional plane of 60% (RES), 100% (CON), or 140% (EXC) of requirements beginning on day 40 of gestation. At parturition, lambs were removed from their dams, and ewes were transitioned to a common diet that met requirements of lactation. Blood samples were taken from a subset of ewes (n = 42) throughout gestation, during parturition, and throughout lactation to determine hormone concentrations. Cotyledon number was reduced (P = 0.03) in RES and EXC compared with CON ewes. Placental delivery time tended (P = 0.08) to be shorter in HSe compared with ASe ewes, whereas placental delivery time was longer (P = 0.02) in RES compared with CON and EXC ewes. During gestation, maternal progesterone, estradiol-17β, and growth hormone were increased (P < 0.05) in RES and decreased (P < 0.05) in EXC compared with CON ewes. In contrast, maternal cortisol, IGF-I, prolactin, triiodothyronine, and thyroxine were decreased in RES and increased in EXC compared with CON ewes during gestation. Selenium supply did not alter maternal hormone profiles during gestation. During parturition and lactation, maternal hormone concentrations were influenced by both Se and maternal nutritional plane. During the parturient process, HSe ewes tended to have greater (P = 0.06) concentrations of estradiol-17β compared to ASe ewes. Three h after parturition there was a surge of growth hormone in ASe-RES ewes that was muted in HSe-RES, and not apparent in other ewes. Growth hormone area under the curve during the parturient process was increased (P < 0.05) in ASe-RES vs HSe-RES ewes. Ewes that were overfed during gestation had reduced (P < 0.05) estradiol-17β, but greater IGF-I, T3, and T4 (P < 0.05) compared to RES ewes. Even though ewes were transitioned to a common diet after parturition, endocrine status continued to be impacted into lactation. Moreover, it appears that gestational diet may partially impact lactational performance through altered endocrine status.

      PubDate: 2013-10-04T21:21:39Z
  • Possible role of IGF2 receptors in regulating selection of 2 dominant
           follicles in cattle selected for twin ovulations and births
    • Abstract: Publication date: Available online 4 October 2013
      Source:Domestic Animal Endocrinology
      Author(s): P.Y. Aad , S.E. Echternkamp , L.J. Spicer
      Abundance of IGF-2 receptor (IGF2R), FSH receptor (FSHR), and LH receptor (LHCGR) mRNA in granulosa cells (GCs) or theca cells (TCs) or both cells as well as estradiol (E2), progesterone (P4), and androstenedione concentrations in follicular fluid were compared in cows genetically selected (Twinner) or not selected (control) for multiple ovulations and twin births. Cows were slaughtered at day 3 to 4 (day 3) and day 5 to 6 (day 5) of an estrous cycle, and ovaries, follicular fluid, GCs, and TCs were collected. The two largest (F1 and F2) E2-active (EA) and E2-inactive (EI) follicles were selected according to their E2-to-P4 ratio and diameter. Androstenedione levels in EA F1 and F2 follicles were 5-fold greater (P < 0.05) in Twinner cows than in control cows on day 3 but did not differ on day 5. Twinner cows also had greater (P < 0.05) E2 and P4 concentrations, whereas steroid levels in EI follicles did not differ (P > 0.10) between genotypes. In EA F2 follicles, IGF2R levels in GCs were greater (P < 0.05) in control cows than in Twinner cows on day 3 and day 5, whereas IGF2R mRNA in TCs did not differ (P > 0.10). On day 3, FSHR mRNA levels were greater (P < 0.05) in GCs of EA F1 and EI F2 follicles of control cows than of Twinner cows. LH receptor mRNA expression was less in GCs and greater in TCs of EA F2 follicles in control cows than in Twinner cows (P < 0.05). We hypothesize that reduced GC IGF2R expression in F2 follicles of Twinner cows may play a role in the development of 2 or more dominant follicles.

      PubDate: 2013-10-04T21:21:39Z
  • Heat-tolerant versus heat-sensitive Bos taurus cattle: influence of air
           temperature and breed on the metabolic response to a provocative immune
    • Abstract: Publication date: Available online 19 September 2013
      Source:Domestic Animal Endocrinology
      Author(s): N.C. Burdick Sanchez , R. Chaffin , J.A. Carroll , C.C. Chase Jr. , S.W. Coleman , D.E. Spiers
      The response of the immune and stress systems have been assessed in response to a lipopolysaccharide (LPS) challenge, yet the role of metabolism in mediating energy requirements during the acute-phase response has not been sufficiently studied. This study tested heat-tolerant (Romosinuano [RO]) and heat-sensitive (Angus [ANG]) Bos taurus breeds at different ambient temperatures (Ta) to determine differential metabolic responses to LPS challenge. Twenty-one heifers (ANG: n = 11, 306 ± 26 kg BW; RO: n = 10, 313 ± 32 kg BW) were housed in stanchions in 4 temperature-controlled chambers. Initially, Ta in all 4 chambers was cycling at thermoneutrality (TN; 18.5°C–23.5°C) for a 1-wk adjustment period, followed by an increase in 2 chambers to cycling heat stress (HS; 24°C–38°C) for 2 wk. Five ANG and 5 RO heifers were housed at TN, whereas 6 ANG and 5 RO heifers were housed at HS. On day 19, heifers were fitted with jugular catheters. On day 20, heifers were challenged with LPS (0.5 μg/kg BW; 0 h), and blood samples were collected from −2 to 8 h and at 24 h relative to LPS challenge. Serum was analyzed for glucose, insulin, and NEFA concentrations. In addition, feed intake was measured 3 d before and on the day of the challenge. Feed intake decreased over time (P < 0.001) and was decreased in heifers housed at HS compared with heifers housed at TN (P = 0.013). Glucose concentrations before LPS challenge were greater in RO (P = 0.01) than in ANG heifers and greater in TN-housed heifers (P = 0.02) than in HS heifers. Glucose after LPS challenge initially increased before decreasing below baseline concentrations (P < 0.01) in all heifers. In addition, a breed by Ta interaction (P < 0.004) was found, such that HS decreased glucose concentrations in ANG heifers compared with ANG heifers housed at TN (P < 0.001), whereas HS did not affect glucose concentrations after LPS challenge in RO heifers (P = 0.941). Nonesterified fatty acid concentrations before LPS challenge were not affected by breed (P = 0.37) or Ta (P = 0.60). Although NEFA concentration after LPS challenge was unaffected by Ta (P = 0.78), there tended to be a breed by Ta interaction (P = 0.07) such that, when housed at HS, RO heifers had greater serum NEFA concentrations after LPS challenge than ANG heifers (P = 0.009). Insulin concentration before LPS challenge was greater in RO heifers than in ANG heifers (P < 0.01). Insulin after LPS challenge increased (P < 0.01), with RO heifers producing a greater insulin response than ANG heifers (P < 0.01). These data suggest that HS decreases the metabolic response of heat-sensitive ANG heifers in response to LPS challenge, thus providing physiological evidence that may explain differences observed in the acute-phase response between heat-sensitive ANG and heat-tolerant RO cattle breeds.

      PubDate: 2013-09-21T22:48:25Z
  • Expression of the cannabinoid receptor type 1 in the pituitary of rabbits
           and its role in the control of LH secretion
    • Abstract: Publication date: Available online 21 September 2013
      Source:Domestic Animal Endocrinology
      Author(s): C. Dall'Aglio , P. Millán , M. Maranesi , P.G. Rebollar , G. Brecchia , M. Zerani , A. Gobbetti , G. Gonzalez-Mariscal , C. Boiti
      The aim of this study was to elucidate the possible direct regulatory role of the endocannabinoids in the modulation of LH secretion in rabbits, a reflex ovulator species. The cannabinoid receptor type 1 (CB1) was characterized by RT-PCR techniques in the anterior pituitary of intact and ovariectomized does treated with GnRH and primed with estrogen and CB1 antagonist, rimonabant. cannabinoid receptor type 1 immune reaction was evidenced by immunohistochemistry in the cytoplasm of approximately 10% of the pituitary cells with a density of 8.5 ± 1.9 (per 0.01 mm2), both periodic acid–Schiff positive (30%) and negative (70%). All CB1-immunoreactive cells were also immune reactive for estrogen receptor type 1 (ESR1). Ovariectomy, either alone or combined with estrogen priming, did not modify the relative abundances of pituitary CB1 mRNA, but decreased (P < 0.01) the expression of estrogen receptor type 1 mRNA. Treatment with CB1 antagonist (rimonabant) inhibited (P < 0.01) LH secretory capacity by the pituitary after GnRH injection, and estrogen priming had no effect. The present findings indicate that the endocannabinoid system is a potential candidate for the regulation of the hypothalamic-pituitary-ovarian axis in reflex ovulatory species.

      PubDate: 2013-09-21T22:48:25Z
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