Influence of climatic conditions on in vitro production of bovine embryos

• Autor(a) principal: Pessoa,G.A
• Data de Publicação: 2010
• Outros Autores: Navarro,R.B, Rauber,L.P, Brass,K.E, Silva,C.A.M, Rubin,M.I.B
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Arquivo brasileiro de medicina veterinária e zootecnia (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352010000600013
• topic: cow; oocytes; embryo; climate; in vitro prodution

Temperature and rainfall were analyzed daily during six years to evaluate their influence on in vitro production of bovine embryos. Weekly replications (n=480) were performed on 14,778 ovaries collected at slaughterhouses. Cumulus oocyte complexes (n=19,180) were fertilized with a pool of Bos taurus taurus semen in one incubator with 5% CO2. Presumable zygotes were cultured in gasified plastic bags with 5% CO2, 5% O2, and 90% N2. In the first year, cleavage and embryo yield were 60.3% and 15.6%, respectively, being lower (P<0.05) than in the following years. Average cleavage rates were always lower in winter (P<0.0001), thus producing less embryos. Winter climatic conditions had a negative influence on in vitro production, when cleavage and embryo yield declined, possibly because of reduced availability and growth of native pasture.