Effects of maternal and dietary selenium (Se-enriched yeast) on oxidative status in testis and apoptosis of germ cells during spermatogenesis of their offspring in goats

To investigate the effect of maternal and dietary selenium on antioxidant status in testis and apoptosis of germ cells during spermatogenesis of their offspring, selected Taihang Black Goats (n = 119) were randomly allotted to four treatment groups. They were fed the experimental diet with different Se levels (from Se-enriched yeast) for 174d from 60d prior to lactation to weaning of kids. The treatments were: (1) Group 1 (control), basal diet without Se supplementation, (2) Group 2, the same basal diet supplemented 0.5 mg Se/kg DM, (3) Group 3, the same basal diet supplemented 2 mg Se/kg DM and (4) Group 4, the same basal diet supplemented 4 mg Se/kg DM. Thirty days after weaning, testis samples of the young male goats were collected for mRNA expression and analyzing the antioxidant status and Se concentration, as well as the population of apoptotic germ cells by TUNEL assay. The results show that mRNA expression of apoptosis genes (Bcl-2, Bax and Caspase 8) were significantly higher in Groups 1 and 4 than that in Groups 2 and 3. The same trend was observed in the population of apoptotic cells analyzed by TUNEL assay. GSH-Px activity and Se concentration in testis of offspring was progressively increased with the increasing Se level in diet of dams. However, there was no significant difference in GSH-Px activity between Groups 3 and 4. The lowest MDA content was obtained in Group 2 and a significant decrease was observed in Groups 1, 3 and 4. These data suggest that doe maternal and dietary Se could influence antioxidant status in the testis of their offspring and the oxidative stress related to Se from the dam could modulate mRNA expression of apoptosis genes and apoptosis of germ cells during spermatogenesis. It is possible that Se supplementation of the damʹs diet during gestation and lactation could be a way to supply the Se necessary for normal development of reproductive function of their offspring.