Lysine nutrition in swine and the related monogastric animals: muscle protein biosynthesis and beyond

Abstract

Improving feed efficiency of pigs with dietary application of amino acids (AAs) is becoming increasingly important because this practice can not only secure the plasma AA supply for muscle growth but also protect the environment from nitrogen discharge with feces and urine. Lysine, the first limiting AA in typical swine diets, is a substrate for generating body proteins, peptides, and non-peptide molecules, while excess lysine is catabolized as an energy source. From a regulatory standpoint, lysine is at the top level in controlling AA metabolism, and lysine can also affect the metabolism of other nutrients. The effect of lysine on hormone production and activities is reflected by the change of plasma concentrations of insulin and insulin-like growth factor 1. Lysine residues in peptides are important sites for protein post-translational modification involved in epigenetic regulation of gene expression. An inborn error of a cationic AA transporter in humans can lead to a lysinuric protein intolerance condition. Dietary deficiency of lysine will impair animal immunity and elevate animal susceptibility to infectious diseases. Because lysine deficiency has negative impact on animal health and growth performance and it appears that dietary lysine is non-toxic even at a high dose of supplementation, nutritional emphasis should be put on lysine supplementation to avoid its deficiency rather than toxicity. Improvement of muscle growth of monogastric animals such as pigs via dietary lysine supply may be due to a greater increase in protein synthesis rather than a decrease in protein degradation. Nevertheless, the underlying metabolic and molecular mechanisms regarding lysine effect on muscle protein accretion merits further clarification. Future research undertaken to fully elucidate the metabolic and regulatory mechanisms of lysine nutrition could provide a sound scientific foundation necessary for developing novel nutritional strategies to enhance the muscle growth and development of meat animals.

Effect of Dietary Lysine Regimens on Growth Performance and Meat Composition in Aseel Chicken

“…The reason behind is because the fact that Lys integral component for protein synthesis, any deficiency of Lys can limits the immune related protein synthesis includes antibodies and cytokines. Chen et al (2003) reported that Lys deficiency negatively affects antibody response f and cell mediated immunity, also showing adverse effects on growth performance (Liao et al 2015). Similar to the current study, Mushtaq et al (2015) fed higher Lys level to the birds and observed reduced mortality, concluding that higher Lys levels in the diets improves livability.…”

“…Moreover, improved F:G in high and medium Lys groups may be attributed to the higher WG and lower FI in the same groups. On the other hand, decreased WG diet may be explained by the fact that inadequate Lys supply depresses the immune system of the birds (Geraert & Mercier2010) showing adverse effects on livability and growth performance (Liao et al 2015). Similarly, it was reported that depressed growth in Lys deficient diets may be due to decreased protein synthesis and accretion (Tesseraud et al 1996).…”

“…Chickens grow faster at a relatively high dietary Lys concentration in the diet compared with diet deficient in Lys (Li et al 2013). Deficiency of Lys in the diet results in decreased protein synthesis and accretion (Liao et al 2015). Keeping in view all above discussion, it was hypothesized that balanced diet supplemented with Lys may ameliorate the early poor growth rate of indigenous Aseel chicken.…”

An aquatic vertebrate can use amino acids from environmental water

“…The vital roles played by different amino acids may also influence the magnitude of the effect. For example, lysine can serve as a substrate for growth hormones [35], and tyrosine and phenylalanine are inducers of catecholamine, which forms the basic structure of neurotransmitters [36]. The ability of each amino acid to penetrate the surfaces of the gut, skin, and gills might also determine the effect magnitude; amino acids with a better penetrative ability could have better usability as a source of nutrients or growth-promoting factors.…”

Effects of Dietary Lysine Levels on the Plasma Concentrations of Growth‐Related Hormones in Late‐Stage Finishing Pigs

“…The biochemical process of protein turnover in the skeletal muscle of pigs is of great importance for the production of food protein for human consumption [1]. Some nutrients, such as glucose and fatty acids, play important roles not only as energetic substrates but also as cell signaling molecules to regulate the protein turnover in animal body [2][3][4].…”