Evaluation of the simulated physiological oocyte maturation (SPOM) system on F1 Gyr × Holstein oocytes and embryos
The present study aimed to evaluate the effect of the simulated physiological oocyte maturation (SPOM) system on F1 Gyr × Holstein oocytes and embryos by evaluating the meiotic arrest, embryo production rates, total number of cells and lipid score. Three experiments were conducted and the following three experimental groups were formed according to in vitro maturation (IVM) treatments: CONTROL 1 (TCM 199 medium without FBS), CONTROL 2 (commercial medium) and SPOM (TCM 199 medium with forskolin and 3-isobutyl-1-methylxanthine (IBMX) in pre-IVM and extended IVM with cilostamide). In the first experiment (ovum pick-up), a significant (P < 0.05) reduction in the percentage of matured oocytes in SPOM group was observed. In the second (slaughterhouse ovaries) and third (ovum pickup) experiments, the cleavage and blastocyst rates were reduced (P < 0.05) in the SPOM group. There was no significant (P > 0.05) difference in total number of cells among the groups. No difference (P > 0.05) was found on lipid score among the groups at Day 7 of development, in both Experiments 2 and 3. At Day 9 (Experiment 2), only the CONTROL 2 showed a significant increase (P > 0.05) compared with the other treatments. It was concluded that under our conditions, the SPOM system was efficient in prolonging meiotic arrest on Gyr × Holstein oocytes, offering the oocytes in vitro conditions more similar to those found in vivo; however, it adversely affected embryo production rates and promoted no beneficial effect on the total number of cells and the lipid score.