Denis Faustino Alves

Desenvolvimento embrionário in vitro de oócitos bovinos mantidos em líquido folicular ou TCM-hepes

In order to evaluate the effect of a transport medium on the rate of in vitro embryonic development, 1381 Cumulus-oocyte Complexes (COC) were obtained by aspiration of 2-8mm diameter follicles witch were randomly divided in 4 treatment groups. The Control group was formed by oocytes matured in modified TCM-199 for 24h, incubated at 39°C and 5,00% CO2 with saturated humidity. The group 1 (WB24h), included oocytes matured in 1.0mL tubes containing TCM-HEPES (5.95mg/mL), in water bath (WB) at 39°C for 24h. The group 2 (FFb6C18h), included oocytes kept in bovine follicular fluid (FFb) for 6h at 30°C followed by a period of 18h maturation under the same conditions as the Control group and with the oocytes maintained in FFb followed by 18h IVM under the same conditions as the group 1, group 3 (FFb6WB18h). Fertilization was performed in FERT-TALP for 18h. Zygotes were cultured in SOFaaci under mineral oil within gasified bags. The cleavage rate differed (P<0.05) between the Control and FFb6BM18h groups. However, there was no difference on the D7 and D9 blastocyst rates and on the percentage of blastocyst ecloded. It was concluded that it is possible to maintain the oocytes in FFb for 6h at 30°C before 18h IVM, or to proote the transport and maturation of the oocytes for 24h, in TCM-HEPES and water-bath at 39°C, without compromising embryonic development. The simplification of MIV showed in this experiment through of tubes (1.0mL) replete with TCM-HEPES and holding in water bath at 39°C, could be a viable and practice for the bovine programs of OPU/PIV.

Desenvolvimento embrionário de oócitos bovinos mantidos em fluido folicular bovino de folículos de diferentes diâmetros

Bovine oocytes have been maintained in the follicular fluid to be transported and to increase their competence, before maturation. Eight hundred eighty-one (881) oocytes, aspirated from bovine slaughterhouse ovaries, were used to evaluate the effect of holding bovine oocytes in follicular fluid (FF) of bovine follicles of different diameters on the rate of embryo development. The oocytes were randomly distributed in four treatments with seven replicates each: The control group (n=217) was constituted by oocytes matured for 24h in modified TCM-199 with Estrus Mare Serum (EMS), pyruvate and rFSH-h in incubator with 5,00% CO2, 39°C and saturated humidity. In the FFsmall group (3 to 5mm follicles; n=216), the oocytes were held for 6h in follicular fluid at 30°C and matured for 18h in the same conditions of the Control-group. The oocytes of the FFmedium group (5,1-8mm follicles; n=226) and of the FFlarge group (>8,1mm follicles; n=222) were held in follicular fluid and matured like FFsmall. Fertilization was accomplished during 18h and, after this, the zygotes were cultured for 8 days in SOFaaci medium + 5,00% EMS in incubator at 39°C using plastic bags gasified with 5,00%CO2, 5,00%O2 and 90,00%N2. FFsmall oocytes produced a lower (P 0,05) between the groups. Follicular fluid of medium and large follicles could be used to hold for 6h at 30°C bovine oocytes before their maturation for 18h.