Oocytoe production and in vitro maturation in Canindé goats following hormonal ovarian stimulation
Avelar, S R GMoura, R RSousa, F CPereira, A FAlmeida, K CC H S meloTeles-Filho A C ABaril, GTeixeira, D I AFreitas, V J F
This study e valuated the effect of hormonal ovarian stimulation regimes on the quantity and quality of the cumulus - oocyte complexes (COCs) recovered by laparoscopy and their subsequent in vitro matur ation (IVM) . Eighteen cyclic Canindé goats received a vaginal sponge with 60 mg m edroxyprogesterone acetate for 11 days, together with a n injection of 50 μg d - cloprostenol on the 8 th day , along with additional treatment re g imens , as follows : i) five doses (5D), 120 mg of NIH - FSH - P1 in five injections at 12 h inter vals; ii) three doses (3D), 120 mg of NIH - FSH - P1 in three injections at 24 h i nterv als; iii) single dose (1D), 70 mg of NIH - FSH - P 1 and 200 IU of eCG at 36 h prior to sponge rem oval. Three sessions of hormonal treatment/oocyte recover y w ere performed and goats ( n = 6 / group) were allocated to different grou ps . The oocytes were collect ed by laparoscopy at the time of sponge removal and the IVM of the oocytes was monitored. A total of 14.8 ± 0.8 follicles were aspirated per animal with 11.1 ± 0.6 COCs being rec overed , resulting in a recovery rate of 74.7 % ( 577/772 ) . The mean number of CO Cs/goat did not differ (P > 0.05) between treatments (11.7 ± 1.1, 10.7 ± 0.9 and 10.8 ± 1.0 for the 5D, 3D and 1D groups, respectively). R ecovery rate was higher (P < 0.05) in the 5 D group ( 84.1 % ; 211/251 ) compared to the 3 D ( 68.2 % ; 182/267 ) and 1D group s (72.4% ; 184/254 ). T he lowest (P < 0.05) maturation rate was recorded in the 3D group (32.1% ; 27/84 ), while the rate for the 5D and 1D groups was 49.1% ( 53/108 ) and 46.2% ( 42/91 ) , respectively. Finally, taking into account the main performance results of th e three treatments, it i s advisable to use the 5D regime in future Canindé breed preservation programs based on laparoscopy technology as a means to recover oocytes .(AU)
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