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Laparoscopic oocyte recovery (LOR) is a valuable tool for obtaining oocytes for in vitroembryo production. When preceded by a treatment of ovarian stimulation, this technique produces an increase in the amount of oocytes recovered. However, a little information has been found to respect the effect of successive hormonal treatments on both oocyte quantity and quality. Therefore, the objectives of this study were to evaluate the ovarian response and quantitative and qualitative COC production. Five adult crossbred goats were hormonally treated with intravaginal sponges containing 60 mg of medroxyprogesterone acetate (MAP, Progespon, Syntex, Buenos Aires, Argentina) for 11 days. In the 8th day of progestagen treatment, 50 μg of prostaglandin F2α analogue (Ciosin, Coopers, São Paulo, Brazil) was administered by i.m. injection. At this time, ovarian stimulation was initiated by the administration of 120 mg pFSH (Folltropin-V, Vetrepharm, Canada) distributed in five decreasing doses (30/30, 20/20, 20 mg), at 12-h intervals. The animals were fasted for 24 h before the laparoscopic procedure, which was performed just after the sponge removal. A laparoscopic system connected to a 22-gauge needle (WTA, Watanabe, Brazil) and a vacuum pump (Biovacuum, Biocom, Brazil) providing 30 mm Hg was used. All follicles with a size larger than 2 mm present in both ovaries were counted and aspirated. The collection medium was TCM-199 supplemented with HEPES (10 mM), heparin (20 IU mL-1), and gentamicin (40 μg mL-1). The COCs were graded based on presence of cumulus cells and cytoplasm homogeneity (I to IV). The hormonal treatment and LOR procedures were repeated three times at 14-day intervals. Data were expressed in percentage or mean ± SEM. The differences were analyzed using ANOVA and Tukey''s or Fischer''s exact test when appropriate, with P 0.05) for the number of follicles obtained in each LOR session: 17.0 ± 3.91, 18.75 ± 2.59, and 18.0 ± 4.73, respectively. Repeated LOR procedures also did not affect (P> 0.05) the number of aspirated follicle (15.0 ± 3.92, 15.5 ± 2.33, and 16.0 ± 4.36), resulting from the three sessions, respectively. Average recovery rates were not statistically different (P> 0.05), resulting in 74.7%, 62.9%, and 64.6% between sessions. With respect to the percentage of viable COCs (GI and GII) were not observed statistical differences (P> 0.05), as verified the follow values at 1st to 3rd sessions: 76.79%, 84.62%, and 74.19%. In conclusion, three successive hormonal stimulation LOR procedures did not cause detrimental effects on quantitative and qualitative oocyte production, suggesting that this protocol can be used for programs of in vitrogoat embryo production. This study was supported the following Brazilian agencies: FINEP, CNPq, FUNCAP, and CAPES. [ABSTRACT FROM AUTHOR]

Oocyte IVM is a long process during which oocytes acquire their ability to support the stages of development in a stepwise manner, ultimately reaching activation of the embryonic genome. The overall success of this process can be affected by factors such as hormonal treatment for ovarian stimulation. Thus, the current study aims to evaluate the possible effects of the ovarian stimulatory protocols on the goat oocyte quality and IVM rate. Adult and cyclic Canindé goats were heat-synchronized by means of intravaginal sponges impregnated with 60 mg medroxyprogesterone acetate (MAP, Progespon, Syntex, Buenos Aires, Argentina) inserted for 11 days coupled with a luteolytic injection of 50 μg cloprostenol (Ciosin, Coopers, São Paulo, Brazil) in the 8th day of treatment. The ovarian stimulation was carried out using one of the following protocols: a) standard multi-doses (MD) with 120 mg pFSH (Folltropin-V, Vetrepharm, Canada) distributed in five injections (30/30; 20/20; 20 mg) at 12 h intervals (n= 18); b) three- doses (TD) with 120 mg pFSH administered in three injections (60; 40; 20 mg) at 24 h intervals (n= 17); c) one shot (OD) of 70 mg pFSH plus 200 IU of eCG (Novormon, Syntex) administered 36 h before sponge removal (n= 17). In MD andTD groups, the pFSH injections started in Day 8 of progestagen treatment. The follicles were aspirated just after the sponge removal using laparoscopic oocyte recovery (LOR). This procedure was performed with a 22-gauge needle and a vacuum pump at 30 mmHg. The collection medium was TCM-199 supplemented with HEPES (10 mM), heparin (20 IU mL-1), and gentamicin sulfate (40 μg mL-1). COCs were classified as grade I, II, III, or IV based on visual criteria (Baldassarre H et al.2003 Theriogenology 56, 831-839). Good quality oocytes (grade I and II) were incubated in TCM-199 supplemented with cysteamine (100 μM), EGF (10 ng mL-1) and gentamicin sulfate (40 μgm L-1) at 38.5°C in a humidified atmosphere with 5% CO2in air for 24 h. Oocyte maturation was assessed by the visualization of first polar body under inverted microscope. Data were expressed as percentages and analyzed using the Fischer''s exact test. No statistical differences among hormonal treatments (P> 0.05) were observed for the percentage of the good quality oocytes, with 70.4 ± 3.0% of COCs graded in I and II. The IVM rate inTD (31.4%) was statistically lower than MD (31.4% v.46.5%, P= 0.04) group. However, no significant differences (P= 0.89) were observed between OD (45.2%) and MD groups. Thus, current results indicate that oocyte production for IVM can be facilitated using ovarian stimulation with the one shot FSH/eCG regime without affecting meiotic competence. In summary, OD and MD treatments can be used for oocyte IVM in an embryo production programme in Canindé goats. This study was supported by the following Brazilian agencies: FINEP, CNPq, FUNCAP, and CAPES. [ABSTRACT FROM AUTHOR]