Gene expression and embryo quality in superovulated goats supplemented with crude glycerin after mating

This study aimed to assess the effects of dietary supplementation with crude glycerin on embryo quality and expression profile of genes from superovulated goats. Twenty-four hours (1 day) and 72 h (3 days) after mating animals received an oral drench of 200 mL saline solution (Control group), 100 mL glycerol (100 mL group) or 200 mL glycerol (200 mL group). Both insulin and glucose levels were measured after glycerol drenching. The relative expression of genes (Glut-1, IGF-1, Hsp70, Sod and Bax) in grade I and II embryos from groups was analyzed by sensitive TaqMan qPCR. Administration of crude glycerin raised insulin and glucose (p < 0.05) plasma concentrations. Similar rates of superovulatory response (94.12%; 16/17) and recovery of transferable embryos (N embryo grades 1, 2 and 3/N ovulation), (44.69 ± 6.83%; 100/224) were obtained. The 200 mL group showed a greater proportion of transferable embryos compared to the degenerated embryos (8.83 ± 2.30 vs. 1.17 ± 0.83, p < 0.05), that achieved values 2-fold higher than control group (4.80 ± 2.30 vs. 0.20 ± 0.20, p < 0.05) and 100 mL group (3.83 ± 1.25 vs. 1.17 ± 0.48, p > 0.05). A higher relative abundance of IGF-1 transcripts was observed in 200 mL group. Also none differences were observed for transcripts of apoptotic (Bax) and stress (Hsp70) genes. In conclusion, enhancement of circulating glucose and insulin generated from drenching crude glycerin after mating was associated with higher IGF-I expression and increased proportion of transferable embryos.