Características físicas e fecundidade do sêmen de jumentos coletado de forma fracionada e preservado resfriado a 5ºC

• Ano de defesa: 2011
• Autor(a) principal: Laura Enes de Carvalho
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: coleta fracionada; fertilidade; jumento; sêmen resfriado; Reprodução animal; Veterinária; Semen Analise; Fecundidade; Asinino Reprodução
• Link de acesso: http://hdl.handle.net/1843/BUOS-8PLHYU

The present study was conducted from September 2010 to February 2011, in Lagoa Dourada, Minas Gerais, in the southest region of Brazil. The objectives of this study were to evaluate: a) the jets of the sperm rich fraction ejaculated by jackasses (Experiment I EI); b) two diluters: skim milk-glucose - SMG or egg yolk-lactose EYL (Experiment II EII) and two different sperm concentrations (400 or 800 x 106/AI dose; Experiment III EIII ) on semen preservation and on mares conception rate inseminated with fractionated jackass semen cooled at 5oC; c) the viability of fractional collection of semen carried out by the split-ejaculate method and d) the semen quality and fertility of 5 different Pêga jackasses. In EI the three first jets of the sperm-rich fraction were evaluated to compare differents characteristic among jets and jackasses. The sperm rich fraction semen was diluted (EII), cooled to 5oC and stored for up to 48 hours, using 22 mL as a total dose with different concentrations (EIII). The semen were evaluated as fresh, pre-diluted, pre-artificial insemination and at 24 and 48 hours of storage. Fertility were evaluated using 44 (EII) and 59 (EIII) mares inseminated with stored semen for 12 to 24 hours. The inseminations were done on Monday, Wednesday and Friday, since the mares had one follicle of 30 mm of diameter until ovulation. The pregnancy was detected using rectal ultra-sonography at least 12 days from ovulation. In EI the jets volume were different (p<0.05) between jackasses but similar (p>0.05) between jets. Sperm motility was similar (p>0.05) between jets and jackasses. Sperm vigor didnt differ (p>0.05) between jets of the same animal but the first jet was different (p<0.05) between jackasses. The sperm-rich fraction was composed by three jets with decreasing (p<0.05) concentrations 955.56±64.15, 725.56±64.15 and 280.56±64.15 x 106 sperm/mL. In EII, the semen extended in SMG showed the higher sperm motility than the semen extended in EYL, from the pre-insemination time, when two of the donkeys presented higher results (p<0.05). At 48 hours of storage, the doses of all donkeys, extended in SMG, presented motility values between 45% to 53%, while only one donkey presented motility higher than 30% when EYL was used. The conception/cycle rate using SMG doses was higher (56.52%; p<0.05) than the one got from the use of EYL (4.76%). In EIII semen motility and vigor were similar (p>0.05) between different concentrations, using SMG extender, but different (p<0.05) between jackasses. Stored sperm cells for until 48 hours at 5oC had motility higher than 40% and vigor approximately 3, except for one jackass that had vigor less than 3. The conception/cycle rates were 41.46% and 47.37% (p>0.05) using 400 or 800 x 106/sperm AI dose, respectively. The donkeys were different (p<0.05) from each other when the sperm characteristics were compared, although it didnt influence (p>0.05) the conception rate of inseminated mares