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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) na taxa de maturação nuclear ovocitária do grupo controle negativo (76,7%), quando comparada com a observada em animais com baixa titulação de anticorpos contra o BoHV1 (62,2%). Entretanto, verificou-se menor taxa de maturação nuclear (P

The aim of this study was test the effect of Cordicepim (CY), an inhibitor of mRNA translation, associate with growth factor (IGF-I), in the presence or absence of Roscovitina (Ros), a mitogen promoting factor blocker. Twelve hours in culture media with CY plus 18 or 24 hours of maturation resulted in an average of 80% of oocytes reaching metaphase II. The blastocyst yield after 12 hours culture media with CY plus 18 hours of maturation without inhibition (32.3%) was similar (P>0.05) to the control group (39.6%). A negative effect of Ros on blastocyst yield was observed when not associated to CY, (16.7% in Ros vs 49% in control group). When the concentration of Ros associated with CY was reduced, the blastocyst yield was lower (8.3%) compared with the control group (36.4%). Transmission electron microscopy evaluation showed characteristics like a mature oocyte but also some characteristics of immature oocyte after 12 hours of inhibition. In conclusion, the temporary exposure of bovine oocytes to CY associated with IGF-I during in vitro maturation allowed an increase in culture time with no effect on cytoplasm ultra-structure and blastocyst yield, associated or not with Roscovitina O objetivo desse trabalho foi testar o efeito do Cordicepim (CY), um bloqueador da tradução do RNAm, na maturação citoplasmática do oócito bovino juntamente a um fator de crescimento (IGF-I), associado ou não ao Roscovitina (Ros), um bloqueador do fator promotor da mitose. Doze horas em cultivo com CY seguidos de 18 ou 24 horas de maturação foi suficente para que 80% dos oócitos, em média, atingissem metáfase II. A produção de blastocisto após 12 horas de cultivo em meio com CY seguido de 18 horas (32,3%) de cultivo livre de inibição não apresentou diferença significativa em relação ao grupo controle (39,6%; P>0,05). Um efeito negativo do Ros na produção de blastocistos foi observado quando não associado ao CY (16,7% e 49% de blastocistos, respectivamente). A diminuição na concentração de CY e Ros, quando associados, causou uma queda na produção de blastocisto (8,3% e 36,4% de blastocistos, respectivamente). Utilizando técnica de microscopia eletrônica de transmissão foi possível observar que o cultivo por 12 horas em CY manteve o oócito com algumas características de imaturo, porém com acúmulo e atividades de algumas organelas característico de oócito maturo. Em conclusão, a exposição temporária de oócitos bovinos ao CY associado ao IGF-I, durante a maturação in vitro, permite um aumento no tempo de cultivo, sem afetar a ultra-estrutura citoplasmática do oócito e sem afetar os índices de desenvolvimento embrionário, associado ao Roscovitina ou não