Inclusion of cocoa bran in the diet of lambs and its effect on reproductive parameters.

The objective of the study was to evaluate the effect of the inclusion of cocoa bran in the diet of lambs and its effect on reproductive parameters. For this, 40 lambs were randomly assigned to four treatments, and including 0, 10, 20 and 30% levels of cocoa bran in the concentrate. Blood was collected to measure cholesterol and testosterone and semen for physical and morphological evaluation; testicular biometry and morphometry were also evaluated. There was significant difference (P < 0.05) in body weight and tubulosomatic index between the lambs in the control treatment and those in the 30% cocoa bran treatment. There was no difference in testicular biometry, physical and morphological parameters of fresh semen, testicular morphometry, and volumetric ratio between lambs in all the treatments (P < 0.05). In addition, there was no difference in plasma cholesterol or testosterone concentration (P > 0.05). Thus, it is possible to include up to 30% of cocoa bran in diet without affecting the reproductive parameters of lambs.

Docosahexaenoic acid in diluent for goat semen cryopreservation.

The effects of docosahexaenoic acid (DHA) in the diluent for cryopreservation of goat semen on seminal quality and the optimal levels to be used were evaluated. After collection, semen was pooled and physically evaluated, then divided into four aliquots with different DHA levels in the diluent: 0, 10, 20, and 30 ng mL-1. The semen was cryopreserved in a TK 3000® freezing machine and then thawed for assessment at 37 °C. Sperm motility and vigor, membrane integrity, acrosomal integrity, mitochondrial activity, and sperm chromatin compaction were evaluated after thawing. A completely randomized design was used. For normally distributed variables, ANOVA and regression analysis were used to test for differences between treatments, and for non-parametric data, the Kruskal Wallis test was used at the 5% significance level. There were no differences among groups in terms of membrane integrity, acrosomal integrity, or chromatin compaction. There was a decrease in class I mitochondrial activity with increasing DHA level (P<0.05), but no differences in classes II, III, and IV (P>0.05). The inclusion of 10 to 30 ng mL-1 of DHA in the diluent did not result in improvements in seminal quality parameters after thawing, with some impairment observed in the mitochondrial activity of the sperm cells.

Immunocastration of goats using anti-gonadotrophin releasing hormone vaccine.

The aim of this study was to evaluate the immuno-sterilizing action of anti-gonadotrophin-releasing hormone (anti-GnRH) vaccine in goats. Eighteen male goats were randomly distributed to receive three treatments: T1 (control) - whole animals, and T2 and T3 - application of 0.5 and 1.0 mL of anti-GnRH vaccine, respectively, with six replicates and one goat per experimental unit. Vaccine was administered at 8 months of age and 30 days after the first immunization. Testicular biometry was evaluated monthly, along with seminal collections, for the physical and morphological evaluation of semen. At the time of slaughter, the testicle were collected, and fragments were measured and removed for histological evaluation. The data were evaluated for normality by the Shapiro-Wilk test, followed by appropriate statistical tests for each variable. A reduction in width and length of the right and left testicles was observed and, consequently, the scrotal circumference of the immunized animals reduced after the second vaccine application (P < 0.05). Thirty-days after the first vaccine application, there was a negative effect on seminal production and quality; and 60 days after the second application, a pronounced reduction was observed in all seminal parameters in the vaccinated animals, including azoospermia (83.33% of animals; P < 0.05). Vaccine application reduced testicular weight, seminiferous tubule diameter, and gonadosomatic and tubulosomatic index (P < 0.05), but did not influence the proportion of testicular parenchyma components (P > 0.05). Two applications of the anti-GnRH conjugate are effective for the immunological castration of goats, and the 0.5 mL dose is recommended for use in crossbred goats.