Addition of the oviduct specific protein of porcine (pOSP) and melatonin in maturation media and their effect on the in vitro production of pig embryos

The present study used melatonin and recombinant oviduct specific protein (pOSP) in in vitro maturation medium (IVM). The expansion of the cumulus- oocyte complexes (COCs), the intracellular concentrations of reactive oxygen species (ROS) and embryo development of the different groups were evaluated (C = control; T1 = melatonin; T2 = melatonin and pOSP and T3 = pOSP). Regarding the COCs expansion, the groups T1, T2 and T3 showed satisfactory results compared with group C (P<0.05), but there was no difference between treatments (P>0.05). In the ROS dosage, there was no difference between the mean values obtained in group C (26.4 +/- 10.9) and group 1 (23.4 +/- 7.8). However, in group 2 (21.3 +/- 9.7), the average value was found to be satisfactory in relation group C. Despite that, the average value of treatment 3 (16.6 +/- 10.5) was the most satisfactory result found compared to the other groups (P<0.05). The production of embryos was evaluated by cleavage rate, there was no difference between the values obtained in group C and the values recorded in groups T1 (51.5 %), T2 (50 %), T3 (57.7 %), and among them. This study showed that the pOSP and the melatonin were effective in the improvement of the expansion of COCs cells. In addition, the cells that were treated with pOSP presented a lower amount of ROS, allowing the pOSP to be considered a proteic antioxidant.