Effects of Dietary Alpha-Ketoglutarate Supplementation on Diarrhea Incidence and Nutrient Digestibility in Weaned Piglets Fed Low-Protein Diets

Alpha-ketoglutarate (AKG) supplementation has been explored as a nutritional strategy to mitigate the negative effects of protein restriction. This study aims to evaluate the effects of supplementing a low-protein diet with AKG on growth performance, diarrhea incidence, and fecal nutrient digestibility in weaned piglets. A total of 60 weaned piglets (initial body weight: 7.53 kg; age: 28 days old) were randomly distributed into three dietary treatments with five replicates per group, for a 42-day experimental period. The treatments consisted of a control diet (CT), a low-protein diet (LP), and a low-protein diet supplemented with 1000 g/t AKG (AKG). Fecal samples were collected on days 40–42 to determine the apparent digestibility of nutrients. The results showed that the feed conversion rate (FCR) in LP-group piglets were significantly higher than that of the CT group (p = 0.028), while the crude protein (CP) digestibility was significantly lower in the LP group compared with the CT group (p = 0.038). However, supplementing the low-protein diet with 1000 g/t AKG effectively mitigated these negative effects. Pigs in the AKG group had reduced incidence of diarrhea between days 1 and 14 compared to CT group (p = 0.041). These findings suggest that incorporating 1000 g/t AKG into low-protein diets may reduce post-weaning diarrhea and improve growth performance of piglets.