Arginine metabolism and importante in swine nutrition

Abstract

The swine nutrition in recent years has been the focus of several experimental studies, especially in relation to protein and amino acid nutrition. In this context, arginine is one of the amino acid in increasing research, which metabolism is dynamic, participating in several metabolic pathways and generating numerous compounds. The arginine synthesis occurs primarily in the intestinal-renal axis, where lining cells from the small intestine produce citrulline and proximal tubule cells from kidney extract citrulline from the bloodstream, converting it into arginine, returning it to circulation. Arginine is chemically named 2-Amino-5-Guanidopentanoic Acid, and it is a conditionally nonessential amino acid for pigs, considering that is required primarily from 3 to 21 days age when the animal organism is capable of synthesizing about 60% of its requirements. Thus, arginine supplementation in diets for pregnant and lactating sows has been a tool to increase the performance of nursing piglets. However, there are evidences that high levels of arginine in the diet can cause an antagonism to the lysine, which is the first limiting amino acid for pigs, and it could adversely affect animal performance. Thus, this literature review aims to elucidate the arginine metabolism in swines, evidencing the importance of this amino acid in the nutrition of these animals.