The Effects of Fatty Acid Supplementation During Gestation on Growth and Glucose Metabolism in the Offspring in Sheep

Allison Sanders
Undergraduate (Animal Sciences – Nutrition)
Dr. Alejandro Relling
Animal Sciences

Studies have shown improvements in livestock performance as a result of polyunsaturated fatty acids (PUFA) and monounsaturated fatty acids (MUFA) supplementation, as well as an effect on fetal programming of offspring. In sheep, little is known about how maternal supplementation impacts glucose metabolism in lambs with different levels of intake. This research was conducted to evaluate the performance effects on glucose metabolism and growth rate in fetal programmed lambs fed on different energy intake programs. Fifty days before their expected lambing day, 100 pregnant ewes (n=50, 10 ewes/pen) were supplemented with either 1% of their dry matter intake with calcium salts of MUFA or PUFA. After weaning, the animals were adapted to a high grain diet; and depending on the dam supplementation, wethers were randomly assigned to one of four different treatments (2-3 lambs/pen; 6 pens/treatment). The treatments were: MUFA dam and lamb fed ad-libitum diet, MUFA dam and lamb offered an 85% feed restricted diet (FRD), PUFA dam and lamb fed ad-libitum diet, and PUFA dam and lamb offered an 85% FRD. On day 43 of their diets, 24 lambs were randomly selected to conduct a glucose tolerance test. Lamb performance, plasma glucose and insulin concentrations were analyzed as a randomized complete block design with a repeated measurement procedure (SAS 9.4) considering a 2x2 factorial (dam supplementation and feed intake level). Ewe supplementation in late gestation with fatty acids did not have an impact on lamb performance, nor plasma glucose or insulin concentrations (P >0.61). There was an interaction (P < 0.05) between feed intake group (restricted vs ad libitum) and time on plasma insulin concentration. In conclusion, dam supplementation did not affect offspring's growth or energy metabolism. However, these results may have been impacted by COVID-19 restrictions, which resulted in supplementation ending before the ewes' due dates.