Effects of food restriction on serum concentration of glucose, triacylglycerol, beta-hydroxy butyrate, non-esterified fatty acids and urea in pregnant ewes

Food restriction is a potential unwanted risk for a developing fetus in pregnant ewe. The objective of this study was to study the effects of food restriction on serum concentration of glucose, triacylglycerol, non-esterified fatty acids, beta-hydroxybutyrate and urea in the last 8 weeks of pregnancy in Ghezel sheep (Azerbaijan native). We used Split-plot in time design and the overall sample was 14 Ghezel ewes. After a primary preparation period and using flashing diet, oesterus cycle was synchronized in an out of breeding season with sheep CIDR. Pregnancy induction was carried out through natural mating. Primary sampling (P0) was done 4 weeks after mating and then the ewes were divided and assigned to two groups: Control (T2) and food restriction group (T1). In different stages of pregnancy (P1 – P3) sampling was performed and the above mentioned parameters were measured. We used 16.5-27.5% food restriction. Our results surprisingly showed that food restriction had no statistically significant effect on serum glucose and triacylglycerol concentration, but it had a statistically significant effect on serum beta-hydroxy butyrate, non-esterified fatty acids and urea concentration (p<0.05). Food restriction resulted in mild to moderate ketosis in some individual animals. We conclude that food-restricted pregnant ewes following initial flashing diet at the beginning of pregnancy could maintain their glucose homeostasis and end her pregnancy period by using fat reserves and gluconeogenesis. Only one ewe aborted during food restriction in the end stage of pregnancy and others tolerated the situation.