Serine Supplementation in the Diets of Late Gestating and Lactating Sows Improves Selenium Nutritional Status in Sows and Their Offspring

Serine can regulate selenoprotein expression, and dietary serine is correlated with the contents of plasma selenoprotein P (Sepp1) and milk selenium (Se) in lactating mothers. Based on this, we investigated the effects of serine supplementation in the diets of late gestating and lactating sows on Sepp1 and Se contents in sows and their offspring. A total of 72 sows were assigned to four groups. During the experiment, sows were fed either a basal diet or basal diets supplemented with three different levels of serine. The results showed that maternal dietary serine had no effect on the Se content in the serum of sows and their offspring, whereas it significantly increased the Se content in the liver of piglets at the age of 21 days. Maternal dietary serine significantly increased Sepp1 content, either in the serum of sows or that in their offspring at the ages of 3 days, 7 days, and 21 days. Additionally, maternal dietary serine significantly increased litter weight and the average body weight of piglets at the age of 11 days. Notably, a positive correlation was found between the average body weight of piglets at the age of 11 days and serum Sepp1 content in piglets, at the age of either 3 days or 7 days. In conclusion, maternal dietary serine supplementation could improve Se nutritional status in sows and their offspring. These beneficial changes may contribute to the higher body weight of the offspring.