The objective of this experiment was evaluate the possibility of the use of zebu cattle females with raised genetic quality presenting problems of fertility, acquired after a program of conventional transference of embryos, as oocyte donors in a program of Ovum Pick Up and In Vitro embryo production. Sixteen females of Nelore breed (Bos taurus indicus) with average age of 11 years and 7 months, had been submitted to the same conditions of enviroment, feeding and management. These animals were removed of the program of embryo transfer due fertility problems (ovarian cysts, genital infections and some cases of repeat breedings). The animals had been divided in two groups in agreement the type of pathology: Group I (n=08) formed by animals that had presented ovarians patologies (cysts) and GROUP II (n=08) formed by animals with extra-ovarians patologies, both groups had been submitted to aspiration follicular (OPU) using two types of needles (21G ; 19G ) and pressures (55 e 70mmHg). The two groups were divided in four treatments (T1 =55/21G; T2 = 55/19G; T3 = 70/21G e T4 = 70/19G) and after oocites collection they were submitted to IVP. In this work, 149 aspirations were realised and 879 oocytes were collected (5,9 4,88) GRADE I = 16%; GRADE II = 43%; GRADE III = 21% e GRADE IV = 20%. The averages of oocytes collected in Group I were (T1 = 7,06 5,10; T2= 7,00 3,64; T3 = 10,60 6,51 and T4 = 2,78 2,59) and the second group (GROUP II) (T1 = 4,90 4,47; T2= 2,93 3,05; T3 = 6,11 4,11 and T4 = 2,70 2,00). For the averages of viable oocytes, the results had been the following ones (T1 = 4,35 3,01; T2 = 4,88 2,96; T3 = 6,87 3,91 and T4 = 1,89 1,90) for GROUP I and (T1 = 2,70 2,22; T2 = 1,92 1,98; T3 = 3,47 2,27 and T4 = 2,00 1,05) for GROUP II. In this experiment, 538 oocytes had been taken to the IVP, 161 (32,85%) of these oocytes had clived and 65 (13,26%) had resulted in Morula or Blastocysts. The statistcs analysis of the results did not demonstrate significant difference in the oocyte number of the diferent groups, caused for the suction pressure. It was observed that the type of needle is related of pressure of the vacuum bomb, the best results were finding with T3 treatment, moreover It can be observed through these findings that the best averages of oocytes collected had been gotten in the group of animals that had presented ovarians cysts (GROUP I), We concluded in this experiment that the use of OPU/IVF technique is an great option in the prolongation of the reproductive life in problems zebu cattle.
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