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- Effects of phytase supplementation to reduced-nutrient diets on
performance, egg quality, and economic parameters in commercial layers
Authors: Fabricia A Roque; Priscila S Zorzetto, Brunna G S Leite, Carlos A Granghelli, Jane C Gonçalves, Nury A C R Garcia, Nick Wen, Ulisses R T Moraes, Cristiane S S Araújo, Lúcio F Araújo
Abstract: Background: Exogenous enzyme supplementation is an effective and cost-saving mechanism for increasing the availability of dietary nutrients by increasing digestion and reducing excretion. Objective: To evaluate the effects of phytase supplementation on performance, egg quality, and economic parameters in commercial laying hens fed reduced-nutrient diets from 70 weeks of age. Methods: Novogen White® commercial laying hens (n=256) were randomly allocated to four treatment groups, with eight replicates of eight hens in each group: PC (positive control): conventional diet not supplemented with phytase; diet with reduced levels (RN) of P (-0.12%), Ca (-0.10%), and ME (-14 kcal/kg), and supplemented with 300 phytase units (FTU/kg; RN300FTU); diet with reduced levels of P (-0.16%), Ca (-0.13%), ME (-18 kcal/kg), CP (-8%), synthetic amino acids (-0.01%), and supplemented with 600 FTU phytase/kg (RN600FTU); and diet with reduced levels of P (-0.18% P), Ca (-0.15%), ME (-20 kcal/kg), CP (-20%), synthetic amino acids (-0.01%), and supplemented with 900 FTU phytase/kg (RN900FTU). Results: The layers fed the RN300FTU diet had 2.68% higher egg production than those fed the PC diet. Egg mass produced by PC- and RN300FTU-fed hens was statistically similar. Eggshell thickness was increased in PC-fed hens. Feed cost for the RN900FTU diet was approximately 9% lower compared with that of the PC diet. Conclusion: The best performance and economic results were achieved when layers were fed a reduced-nutrient diet supplemented with 300 FTU phytase.
PubDate: Mon, 23 Jan 2023 00:00:00 -050
- Serum concentrations of corticosterone and sex hormones and their
relationship in farmed Morelet’s crocodile (Crocodylus moreletii)
Authors: Adrián Gutiérrez-Cervantes; Concepción Ahuja-Aguirre, Lorena López-DeBuen, Sergio Viveros-Peredo, Jorge E Morales-Mávil, Felipe Montiel-Palacios
Abstract: Background: Crocodile farming aims to produce high-quality skins from captive crocodilians. Captivity usually exposes the animals to stressful conditions, resulting in increased serum corticosterone (CORT) levels that correlate negatively with those of sex hormones and reproductive success. Objective: To evaluate serum concentrations of CORT and sex hormones and their relationship in farmed Morelet’s crocodiles (Crocodylus moreletii) during the non-breeding (NBS) and breeding (BS) seasons. Methods: The study included 59 adult crocodiles (29 females and 30 males). One blood sample was collected in NBS (n=31) and BS (n=28) from each crocodile to determine serum concentrations of CORT, estradiol (E2), progesterone (P4), and testosterone (T). Crocodiles were kept in mixed-sex groups and were fed once or twice a week throughout the study. Results: In females, CORT was higher in NBS (p<0.05) but had no correlation with E2 or P4 in any season (p>0.05). In males, CORT was similar in NBS and BS (p>0.05) and had no correlation with T (p>0.5). Conclusion: The CORT levels had no effect on sex hormones. This could be explained by low CORT levels resulting from farming conditions where the animals were not exposed to severe or chronic stress.
PubDate: Mon, 19 Dec 2022 00:00:00 -050
- Use of artificial insemination in dairy herds in Northwestern
Rio-grandense, Brazil
Authors: Heitor-José Cervo; Júlio-Otávio Jardim-Barcellos, Vanessa Peripolli, Concepta McManus
Abstract: Background: The use of artificial insemination (AI) in dairy cattle has a direct impact on productivity through genetic improvement and, indirectly, by other technologies that allow for better expression of the genetic potential. Objective: To determine the association between the use of AI and other factors on productive performance of dairy cows. Methods: The study assessed AI impact on 195 dairy farms through the application of structured questionnaires to farmers. Analysis of variance (GLM) was used to evaluate herd milk production and farm size. Multivariate analysis was performed to observe the degree of association between AI and production. Four clusters were formed according to production traits and farm size. Results: Clusters showed high discrimination (90%). Principal factors explained 70% of the variance between clusters. The variables that best explained the variation between clusters were Lactating cows per year, Monthly milk production, Farm area and Total cows. The correspondence analyzes showed that AI use is associated with higher production levels and investment in nutrition, management, genetics, and technology. Conclusion: The use of AI enhances production by increasing productivity and enables greater gains per liter of milk marketed.
PubDate: Tue, 29 Nov 2022 00:00:00 -050
- Effect of management and probiotic supplementation on growth performance
of Muscovy ducks
Authors: Luis Alejandro Arias-Sosa; Alex L Rojas, Isabel Chavarro-Tulcán, Nataly Poveda-Diaz, Jimmy Vargas-Puentes
Abstract: Background: Farming of Muscovy ducks (Cairina moschata) is an important part of the poultry industry in developed countries. However, the lack of research and improvement programs has led to poor productive outcomes in developing regions where this duck breed is important to procure adequate food security. Objective: To evaluate the effect of improved management conditions and the use of commercial probiotics on the growth performance of Muscovy ducks in a semi-intensive system farm in Colombia. Methods: We recorded the weight gain and feed conversion ratio (FCR) of ducks under three treatments: Backyard management, improved management, and improved management plus probiotic supplementation. Results: The backyard farming system led to poor weight gains (male=2,797 g; female=1,605 g) and less efficient FCR (4.06). Improvement of management conditions led to a better (p<0.05) FCR (3.1) and a greater (p<0.05) weight gain (male=2,888 g; female=1,637 g). The FCR under improved management is comparable to those reported in developed duck farming industries, but the final weight was notably lower than those obtained with selected lines. The use of commercial probiotics led to significant (p<0.05) improvement in weight gain (male=2,930 g; female=1,692 g); however, it also increased the FCR (3.5; p<0.05). Conclusions: The improvement of management conditions enhance the productivity of Muscovy ducks, but further genetic selection processes or use of selected lines is required in developing countries such as Colombia. Further studies are required to assess if probiotic supplementation can lead to improvement in Muscovy ducks farming due to the contrasting effect over the weight gain and FCR.
PubDate: Fri, 28 Oct 2022 00:00:00 -050
- Comparing the fibrosis inhibition effect of bevacizumab, 5-fluorouracil,
and mitomycin C in trabeculectomy in dogs with glaucoma: A series of six
cases
Authors: Sandra Patricia Acevedo; Nathalia María Correa Valencia
Abstract: Anamnesis: A descriptive series of six cases of dogs with glaucoma are presented comparing the fibrosis inhibition effect of three drugs used during trabeculectomy (TEC). Clinical findings: The patients were diagnosed with primary chronic closed-angle glaucoma refractory to topical medical treatment with no pupillary light reflex and negative eyeblink response to threat and ocular pain. Therapeutic approach: Two patients received an intraoperative application of bevacizumab; two received 5-fluorouracil; and two, mitomycin C. Intraocular pressure (IOP) and filtering ampoule were observed on days 1, 7, 30, 60, and 90 post-surgery. Results and conclusion: Bevacizumab regulated IOP under 25 mmHg, constituting the drug of choice for dogs with primary closed-angle glaucoma without previous positive response to topical therapy and subjected to TEC, when compared with 5-fluorouracil and MMC regarding the inhibitory effect of fibrosis.
PubDate: Wed, 28 Sep 2022 00:00:00 -050
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