Fertilidade do sêmen congelado de jumento (Equus asinus) da raça pêga em éguas inseminadas pré e pós-ovulação

• Main Author: Ker, Pedro Gama
• Publication Date: 2009
• Format: Master thesis
• Language: por
• Source: LOCUS Repositório Institucional da UFV
• Download full: http://locus.ufv.br/handle/123456789/5674
• topic: Inseminação artificial; Sêmen congelado; Jumento; Artificial insemination; Semen freeze; Donkey; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::PRODUCAO ANIMAL

The objective of this study was to evaluate the fertility of mares inseminated with Pêga donkey’s frozen semen, before and after ovulation. Thirteen semen collections were performed using artificial vagina, Hannover model. Evaluations were performed in fresh, cold and frozen semen in different cryopreservation stages by subjective evaluation of physical parameters and sperm morphology analysis. After collection and physical parameters evaluations, semen was diluted in the minimum contamination medium, centrifuged at 650 g/15 minutes, and resuspended in lactose-EDTA-egg yolk extender. The sperm concentration was 100 million cells/0.5 mL straw. Semen was cooled, stabilized and frozen. The sperm longevity was evaluated using the term resistance test (TRT). The spermatic motility and vigor were evaluated at 0, 30, 60 and 90 minutes after thawing. The SMI was measured using the probes of carboxyfluorescein diacetate and propidium iodide. Forty-eight mares were distributed into two treatments. T1 (n = 25): follicular control performed at six hours intervals and inseminations performed after ovulation. T2 (n = 23): 2000 IU of human chorionic gonadotropin (hCG) application when the follicles reached 35-40 mm in diameter. The follicular control was performed at 12 hours intervals and inseminations 24 hours after hCG application, repeated if ovulation did not occur for 48 hours after gonadotropin application. The inseminations were performed at the apex of the uterine horn ipsilateral of the ovulatory follicle, with a sperm dose of 300 million viable sperm. The motility and the average vigor of fresh semen were respectively 83.07 ± 3.83 and 3.61 ± 0.36; for thawed/frozen semen were 41.92% ± 8.3 and 2.73 ± 0.33. The motility and average vigor of thawed semen at 0, 30, 60 and 90 were 36.9% ± 6.5 and 2.6 ± 0.3, 35% ± 7.1 and 2.5 ± 0.3, 33.8% ± 5.2 and 2.5 ± 0.3, 30% ± 7.1 and 2.5 ± 0.3, respectively. The percentage of intact spermatozoa, semi-injured and injured were 24.9 ± 11.1, 9.9 ± 4.3 and 66.4 ± 8.5, respectively. The fertility was 40% and 26% for treatments 1 and 2, respectively (p> 0.05). For T1, the average time of last follicular control to insemination was 6:35 hours. In T2, the average time of the last insemination to ovulation was 20:16 hours. Its possible to infer that in this work that the average time of 20:16 hours between insemination and ovulation in T2 was longer for the donkey sperm.