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To evaluate the effect of oxytocin as a cervical dilator, a study was carried out on nulliparous goats inseminated transcervically at the beginning of the breeding season. One hundred sixteen nulliparous goats with a mean live weight of 33.4 ± 0.68 kg and an age of 13.7 ± 0.37 months were used. The goats were exposed to active bucks of proven fertility for a period of 14 d in order to induce oestrus. One week later, the Ovsynch protocol was applied, which consisted of the application of 20 mg of gonadorelin (Day Zero), 0.075 mg of cloprostenol (Day 7) and of a second dose of 20 mg of gonadorelin applied on Day 9. Artificial insemination (AI) was performed 16 hr later. Three treatments were evaluated: T1 = 50 IU saline, T2 = 25 IU oxytocin; T3 = 50 IU of oxytocin, intravenously applied 10-15 min before AI. The time required to inseminate each treated goat from groups T2 and T3 was 49.56 and 56.25 s, respectively, versus 85.78 s needed for the goats from group T1 (p < .0001). In the T1 group of goats, the insemination catheter was inserted 2.1 cm into the cervical canal and in goats from groups T2 and T3 it reached 3.41 and 3.77 cm into the cervical canal, respectively (p = .02). Pregnancy rates and prolificacy (kids/doe) were higher (p = .02) for groups T2 (82.93%; 1.16) and T3 (76.92%; 1.21) respectively than for control goats (61.11%; 0.69). In conclusion, the intravenous administration of oxytocin led to greater dilation and depth of cervical penetration, obtaining higher pregnancy rates and prolificacy., (© 2022 Wiley-VCH GmbH.)

The aim of this study was to investigate the effects of exogenous melatonin on libido and semen quality parameters in bucks during the non-breeding season. Twelve bucks of the French alpine breed from 1.5 to 4 years of age were assigned into melatonin (MG) and control (CG) groups, with 6 bucks in each group. The experimental period was 3 months (March-May), divided into six periods of 15 days each. The bucks in the MG group received four melatonin implants at the end of March. Two semen samples were taken from the bucks by artificial vagina once per week and their libido estimated. Volume and spermatozoa concentration, their mass motility and motility, proportion of live and total abnormal and forms with abnormal head and tail were determined in the obtained ejaculate samples. The total number of spermatozoa and functional spermatozoa fraction in the ejaculate was also calculated. The MG bucks had significantly higher mass motility and motility of spermatozoa in the first half of April, and a higher proportion of live spermatozoa in the first and second half of April (p < .05). Differences in libido intensity were not significant. The results indicated that the application of melatonin significantly improved the qualitative parameters of semen in bucks, as seen in increased mass motility, motility of spermatozoa and proportion of live spermatozoa shortly following melatonin insertion. Therefore, the results of the current study are novel regarding the use of melatonin treatment during the non-breeding season to improve the qualitative parameters of ejaculates in bucks., (© 2017 Blackwell Verlag GmbH.)

The metabolism of proteins in the blood serum in Boer and Saanen goats was investigated during puerperium. Twenty Boer goats (10 primiparous and 10 pluriparous) and 10 Saanen goats (five primiparous and five pluriparous) between 2 and 5 years of age were used in this research. Blood for analysis was taken every fourth day from day 3 until day 40 post-partum. Blood samples were collected by jugular puncture. In the obtained blood serum, the concentration of total proteins (PT) and albumin (ALB), and the activity of enzymes aspartate aminotransferase (AST) [the Enzyme Commission number (EC number) 2. 6. 1. 1.], gamma-glutamyltransferase (GGT) (EC 2. 3. 2. 2.), creatine kinase (CK) (EC 2. 7. 3. 2.) and alkaline phosphatase (AP) (EC 3. 1. 3. 1.) were determined by spectrophotometry. These parameters were in physiological ranges in Boer goats and in Saanen goats, without significant differences according to number of kids per doe. According to the research results of the blood serum in goats during puerperium, there were no significant differences in the concentration of ALB. Boer goats had significant higher (p < 0.05) concentration of PT and enzyme activity of AP, CK and GGT. Saanen goats had only enzyme activity of AST significantly higher (p < 0.05). Enzyme activity of alkaline phosphatase was significant higher (p < 0.05) in pluriparous goats in both breeds than in primiparous. The obtained results may represent a contribution to a better understanding of protein metabolism during puerperium in dairy and meat goats and for diagnostic purposes., (© 2010 Blackwell Verlag GmbH.)