Detecção viral e capacidade de maturação in vitro de ovócitos de vacas naturalmente infectadas pelo Herpesvirus bovino 1

• Ano de defesa: 2012
• Autor(a) principal: Mendes, Vívian Rachel de Araújo
• Orientador(a): Costa, Eduardo Paulino da
• Banca de defesa: Luz, Marcelo Rezende
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Medicina Veterinária
• Departamento: Biotecnologia, diagnóstico e controle de doenças; Epidemiologia e controle de qualidade de prod. de
• País: BR
• Palavras-chave em Português: Ovócito bovino; BoHV1; Maturação "in vitro"
• Palavras-chave em Inglês: Bovine oocyte; BoHV1; "In vitro" maturation
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA::REPRODUCAO ANIMAL
• Link de acesso: http://locus.ufv.br/handle/123456789/5099

This study was carried out to verify the presence of DNA of the bovine herpesvirus 1 (BoHV1) in Cumulus Oophorus Complexes (COCs) and in blood, as well as to evaluate the development ability of the oocytes from the naturally infected cows. COCs were obtained from 15 donors through follicular aspiration guided by ultrasound (OPU). The DNA extraction was accomplished in a pool of COCs of all aspirations from a same donor and in the total blood, in order to accomplish the Nested-PCR reactions. The treatments were defined from the title of the antibodies detected by serum-neutralization in microplates, and four groups were established: negative animals (title lower than 2); low title (2 to 8); medium title (16 to 32) and high title (64 to 512). Only the COCs provided with compact layer of cumulus cells, an integral pellucid zone and homogenous cytoplasm were selected for in vitro culture. After 24 hours under culture, the oocytes were fixed and stained for evaluation of the nuclear maturation. The stage of the meiotic cellular cycle was evaluated through an optical microscope with increase of 1000X in immersion. The oocyte reaching the metaphasis stage II was considered as ripe. The DNA of BoHV1 was identified in the pool of COCs from three serum-positive donors, as being not detected in any serumpositive sample. However, the viral DNA was not found in sanguine samples, even in those from the serum-positive animals. No differences (P>0.05) occurred in the nucleus maturation rate of the negative control group (76.7%), when compared with that one observed in animals with low titration of antibodies against BoHV1 (62.2%). However, lower nucleus maturation rate (P <0.05) were verified in oocytes from the cows with average (48.4%) and high titration (50.9%), when compared with negative control. The obtained results allow to conclude that cows naturally infected by BoHV1 can present either viral DNA in ovarian structures and endangerment of the maturation rate of the oocyte nucleus.