Effects of different levels of arginine and methionine in a high-lysine diet on the immune status, performance, and carcass traits of turkeys

Abstract

We postulated that the use of appropriate levels and proportions of arginine ( Arg ) and methionine ( Met ) in compound feed with high lysine content ( Lys ) would make it possible to fully exploit the growth potential of modern fattening turkey crossbreds, without compromising their immune system. The aim of this study was to determine the effect of different ratios of Arg and Met in diets with high Lys content on the performance and immune status of turkeys. The turkeys were assigned to 6 groups with 8 replicates per group and 18 birds per replicate. Six feeding programs, with 3 dietary Arg levels (90, 100, and 110%) and 2 dietary Met levels (30 and 45%) relative to dietary Lys content, were compared. During each of 4 feeding phases (weeks 0–4, 5–8, 9–12, and 13–16), birds were fed ad libitum isocaloric diets containing high level of Lys, approximately 1.83, 1.67, 1.49, and 1.20%, respectively. The dietary treatments had no effect on daily feed intake or body weight at any stage of the study. The protein content of the breast meat was higher in the treatments with the highest Arg level (110%) compared with the lowest Arg level (90%). Similarly, protein content was higher in the treatments with the higher Met level compared with the lower Met level. Higher plasma levels of tumor necrosis factor, interleukin 6 ( IL-6 ), and immunoglobulin Y were found in turkeys fed diets with the lowest Arg content. An increase in Met content resulted in a decrease in plasma content of IL-6. In growing turkeys fed diets high in Lys, an Arg level of 90% relative to Lys can be used without negatively affecting production results and immune system. Regardless of dietary Arg levels, an increase in Met content does not stimulate the immune defense system and shows no effect on growth performance of turkeys in current trial.

The immune status, oxidative and epigenetic changes in tissues of turkeys fed diets with different ratios of arginine and lysine

“…According to Yin et al 42 , dietary Lys deficiency impairs amino acid metabolism and leads to cell apoptosis, thus increasing Casp 3 levels. In one of our previous experiments, neither a decrease in Arg content from 100 to 90% Lys nor its increase to 110% Lys in high-Lys diets 2 affected Casp 3 or Casp 8 levels in turkeys 17 . In another study of turkeys fed low-Lys diets 1 , an increase in Arg content to 110% Lys increased Casp 3 levels 14 .…”

“…Our previous findings indicate that different dietary proportions of Arg relative to Lys (90%, 100% and 110% Lys) in diets with high Lys content, close to the recommendations of breeding companies 2 , have no influence on the growth rate of turkeys 14 . In another experiment, different concentrations of Arg (90%, 100% and 110% Lys) in low-Lys diets 1 had no effect on the final BW of turkeys, except in the youngest birds (aged 1-8 weeks) where the lowest Arg level (90% Lys) decreased BW 17 . In the present study, where turkeys received diets with Lys content consistent with NRC recommendations 1 or 10% higher, the dietary proportions of Arg relative to Lys (95% and 105% Lys) had no influence on the FCR or final BW.…”

“…These studies show that the immune system of vaccinated turkeys can be additionally stimulated by the increased level of the amino acid. Literature data show that apart from Met, also Arg 6,14,20 and Lys 14,17 can stimulate the immune system. The present results do not corroborate the findings of Kubińska et al 26 , because the higher dietary inclusion levels of Lys and Arg, relative to NRC recommendations 1 , had no influence on vaccine-induced antibody titres in turkeys vaccinated against ORT.…”

“…In another experiment conducted by our research team, where turkeys were fed diets with high Lys content (close to the recommendations of breeding companies 2 ), an increase in the inclusion rate of Arg to 110% Lys increased the protein content of breast muscles, but did not improve the growth performance or the immune status of birds. A decrease in dietary Arg content to 90% Lys did not compromise performance only when the inclusion level of Met was increased to 45% Lys 17 . Since our studies of turkeys fed high-Lys diets revealed that low Arg concentration (90% Lys) stimulated the immune system, the question arose as to whether such an Arg:Lys ratio would be sufficient to effectively mobilize the immune system of birds in response to infection.…”

Increased Dietary Inclusion Levels of Lysine Are More Effective than Arginine in Supporting the Functional Status of the Gut in Growing Turkeys

“…It was found that diets with increased levels of Met (45% relative to the content of dietary Lys) and Arg (110% relative to the content of dietary Lys), as compared with the nutrient requirements of turkeys (NRC recommendations) [ 9 ], led to an increase in plasma albumin concentration and in the blood concentrations of caspase-3 and caspase-8. In another study [ 13 ], different dietary Arg:Met ratios affected the performance and immune status of growing turkeys. A higher Arg level in the diet (110% vs. 90% relative to Lys content, close to the BUT recommendations [ 8 ]) decreased the blood concentrations of proinflammatory cytokines (including tumor necrosis factor alpha and interleukin 6), and immunoglobulin Y.…”