Effect of different cryopreservation extenders added with antioxidants on semen quality and in vitro embryo production efficiency in cattle

Abstract

To evaluate the addition of antioxidants in extenders on post-thaw bovine semen quality and in vitro embryo production effi ciency. Six semen samples were collected from fi ve Holstein bulls. In the experiment I, the samples were diluted with AndroMed® and Bovimix® and added antioxidants glutathione (1.5 and 2.5 mM) and melatonin (0.5 and 1.0 mM). In the experiment II, the best treatments obtained in experiment I were used for in vitro fecundation. Glutathione did not improve sperm viability. Melatonin had a negative effect on semen characteristics. Andromed® showed better results in sperm kinetics parameters. Bovimix® was more effi cient in maintaining cell integrity parameters. Signifi cant correlation was found between sperm kinetics parameters and between cell integrity parameters. For in vitro embryo production, after oocyte selection, maturation, fertilization and cultivation were performed using the four treatments previously evaluated. Andromed® was more effi cient in the cleavage rate, no effect of the addition of glutathione. However, the addition of 2.5 mM glutathione in the Bovimix® improved the cleavage rate. There was a signifi cant moderate correlation between cleavage rate and sperm kinetic characteristics. Glutathione did not improve sperm viability. Melatonin reduced the maintenance of sperm characteristics. Andromed® was more effi cient in in vitro embryo production and no effect of glutathione was found in this extender. Addition of 2.5 mM glutathione in the Bovimix® extender provided a higher cleavage rate.