Due to the microbial actions in rumen, ruminants can transform non-quality protein into quality protein like urea, and acquire adequate amino acids for growth. This changes the amino acids profile in diets and affects the optimal amino acid absorption.

Given the significance and complex of amino acid metabolism, extensive efforts have been taken to explore the amino acids (AAs) sensing and transporting in monogastric animal but rarely in ruminants.

Scientists form the Institute of Subtropical Agriculture (ISA) of the Chinese Academy of Sciences found that the first and second limiting AAs of growing goats on a basis of maize stover diet are methionine and lysine.

Recently, an experiment conducted by ZHU Xiaoli, a doctoral student in ISA, illustrated the effects of dietary methionine and lysine supplementation on nutrients digestion, and serum parameters in growing goats.

Dr. ZHU used twenty growing goats and assigned randomly to 4 kinds of diets with different levels of methionine and lysine. MRNA expressions of related amino acid sensing and transporting genes were also analyzed in this research.

Scientists found that although the treatments didn’t affect the nutrients digestion, the dietary methionine and lysine supplementation changed serum amino acids profiles.

Furthermore, the mRNA expression of some amino acid transporters in certain part of intestine was different, and protein synthesis tended to be influenced. Their findings provided valuable information for improving animal production through amino acid nutrition regulation.

This study was supported by the National Natural Science Foundation of China, CAS Visiting Professorship for Senior & Young International Scientists, and Hunan Provincial Creation Development Project.

The research entitled "Effects of dietary methionine and lysine supplementation on nutrients digestion, serum parameters and mRNA expression of related amino acid sensing and transporting genes in growing goats" was published in Small Ruminant Research.