The effect of glycerol or rumen-protected choline chloride on rumen fermentation and blood metabolome in pregnant ewes suffering from negative energy balance

Abstract The objective of this study was to investigate the counteracting effects of glycerol or rumen-protected choline chloride supplementation on rumen fermentation and the profile changes in blood metabolites in pregnant ewes suffering from negative energy balance. Eighteen pregnant Hu sheep with a gestation period of 100 days were used in the present study. Feed restriction was started from 100 days of gestation and lasted for 9 days. During the period of feed restriction, these sheep were randomly assigned to three groups: the control group (CON, n = 6), which received no supplementation, the glycerol group (GLY, n = 6), which received 40 mL of glycerol per day, and the rumen-protected choline chloride group (RPC, n = 6), which received 10 g of rumen-protected choline chloride per day lasted 9 days. All supplements were mixed with feed. The results showed that, compared to CON, glycerol supplementation decreased the proportion of acetate (P d -Glucose have a positive correlation with propionate (r = 0.48, P = 0.02), while have a negative correlation with BHBA (r = −0.77, P