Goat incubator: can bovine oocytes be matured in the uterine horn of a goat?

• Autor(a) principal: FONSECA, J. F. da
• Data de Publicação: 2019
• Outros Autores: BATISTA, R. I. T. P., TREVIZAN, J. T., SOUZA-FABJAN, J. M. G., BRANDÃO, F. Z., CAMARGO, L. S. de A.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da EMBRAPA (Repository Open Access to Scientific Information from EMBRAPA - Alice)
• Texto Completo: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1118709
• topic: Nonsurgical embryo transfer technique; Ex-situ maturation; In vitro maturation; Bovine oocytes; COCs; Goats

Abstract We used a goat as a live incubator, along with associated nonsurgical embryo transfer techniques, to perform ex situ (in vivo) maturation of bovine oocytes. Immature bovine cumulus-oocyte complexes (COCs) aspirated from 3-8 mm follicles from slaughterhouse ovaries were randomly split into two groups for in vitro (IVM; n = 38) and ex situ maturation (ESM; n = 40). IVM was performed for a period of 24 h at 38.5 ºC and with 5% CO2 in the air of maximum humidity. For ESM, a presynchronized nulliparous goat (12 months old) received 40 immature COCs in the uterine horn apiece, via the transcervical route. After 24 h the structures were retrieved through uterine flushing. Analyses of nuclear maturation and lipid quantification were performed on oocytes from both groups. Fluorescent intensity was compared using the Student?s t-test. Forty-seven percent of the structures were recovered after uterine flushing (19/40). The nuclear maturation rate was 94.5% (18/19) and 81.6% (31/38) for the ESM and IVM groups, respectively. In vitro-matured COCs contained more lipid droplets, expressed as a higher amount (p < 0.05) of emitted fluorescent light than ex situ-matured COCs (858 ± 73 vs. 550 ± 64 arbitrary fluorescence units, respectively). This is the first report to associate nonsurgical embryo transfer techniques and a goat as a live incubator for the maturation of bovine oocytes. We conclude that bovine oocytes can progress meiotically in the uterus horn of a goat and that transcervical transfer of bovine oocytes to a goat?s uterus could present an alternative to nuclear maturation.