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

Dietary Artemisia Ordosica Polysaccharide Enhances Spleen and Intestinal Immune Response of Broiler Chickens

The spleen and small intestines are the primary immune organs that provide important immunity against various diseases. Artemisia ordosica polysaccharide (AOP) could be used as an immunologic enhancer to boost immunity in response to infection. This study was performed to explore the effects of the dietary supplementation of AOP on the growth performance and spleen and small intestine immune function in broilers. A total of 288 AA broilers (1 day old) were randomly assigned into six dietary groups. Each group included six replicates of eight broilers per cage. The broilers were fed with a basal diet supplemented with 0 mg/kg (CON), 50 mg/kg chlortetracycline (CTC), 250, 500, 750, and 1000 mg/kg AOP for 42 d. The results showed that dietary AOP supplementation affected broiler growth performance, with 750 and 1000 mg/kg of AOP being able to significantly improve broiler BWG, and 750 mg/kg of AOP was able to significantly reduce the FCR. The dietary AOP supplementation increased the levels of IgA, IgG, IgM, IL-1β, IL-2, and IL-4 in the spleen and small intestine in a dose-dependent manner (p < 0.05). Meanwhile, we found that AOP can promote the mRNA expression of TLR4/MAPK/NF-κB signaling-pathway-related factors (TLR4, MyD88, P38 MAPK, JNK, NF-κB p50, and IL-1β). In addition, the dietary supplementation of 750 mg/kg AOP provides better immunity in the tissue than the CON group but showed no significant difference from the CTC group. Therefore, AOP has an immunoregulatory action and can modulate the immune function of broilers via the TLR4/ NF-ΚB/MAPK signal pathway. In conclusion, dietary supplementation with 750 mg/kg AOP may be alternatives to antibiotics for enhancing broilers' health, immunity, and growth performance.

Increased arginine, lysine, and methionine levels can improve the performance, gut integrity and immune status of turkeys but the effect is interactive and depends on challenge conditions

Arginine (Arg), lysine (Lys), and methionine (Met) can be used to support the health status of turkeys. The present study investigated selected performance, gut integrity, and immunological parameters in turkeys reared in optimal or challenge conditions. The experiment lasted for 28 days, and it had a completely randomized 2 × 3 factorial design with two levels of dietary Arg, Lys and Met (high or low) and challenge with Clostridium perfringens (C. perfringens), Escherichia coli lipopolysaccharide (LPS) or no challenge (placebo). Increased dietary levels of Arg, Lys and Met had a beneficial effect on turkey performance and immunological parameters, and it improved selected indicators responsible for maintaining gut integrity in different challenge conditions. Under optimal conditions (with no challenge), high ArgLysMet diets did not compromise bird performance and they improved selected performance parameters in challenged birds. The immune system of turkeys was not excessively stimulated by high ArgLysMet diets, which did not disrupt the redox balance and had no negative effect on gut integrity. High ArgLysMet diets increased the expression levels of selected genes encoding nutrient transporters and tight junction proteins. However, the influence exerted by different dietary inclusion levels of Arg, Lys and Met on gut integrity was largely determined by the stressor (C. perfringens vs. LPS). Further studies are required to investigate the role of Arg, Lys and Met levels in the diet on the immune response, gut function and performance of turkeys in different challenge conditions.

Metabolic Regulation of Hepatitis B Virus Infection in HBV-Transgenic Mice

Hepatitis B virus (HBV) infection is a worldwide health burden. Metabolomics analysis has revealed HBV-induced metabolism dysregulation in liver tissues and hepatocytes. However, as an infectious disease, the tissue-specific landscape of metabolic profiles of HBV infection remains unclear. To fill this gap, we applied untargeted nuclear magnetic resonance (NMR) metabolomic analysis of the heart, liver, spleen, lung, kidney, pancreas, and intestine (duodenum, jejunum, ileum) in HBV-transgenic mice and their wild-type littermates. Strikingly, we found systemic metabolic alterations induced by HBV in liver and extrahepatic organs. Significant changes in metabolites have been observed in most tissues of HBV-transgenic mice, except for ileum. The metabolic changes may provide novel therapeutic targets for the treatment of HBV infection. Moreover, tissue-specific metabolic profiles could speed up the study of HBV induced systemic metabolic reprogramming, which could help follow the progression of HBV infection and explain the underlying pathogenesis.

The effect of the application of diets with varied proportions of arginine and lysine on biochemical and antioxidant status in turkeys

The aim of the study was to determine the effect of two proportions of arginine (95% and 105%) relative to lysine (Lys), where Lys content in the diet is in accordance with NRC (1994) recommendations or 10% higher, on the metabolism, antioxidant status, and growth performance of turkeys. The experiment had a 2x2 factorial design with two levels of Lys and Arg. The diets with a low level of Lys were according to the NRC (1994) requirements. In the diets with a high level of Lys, the content of Lys was increased by 10% relative to the low level Lys. The two Arg levels in the experimental diets were determined so as to provide 95% and 105% Arg relative to the content of dietary Lys. An increase in the amount of Lys in the diet of turkeys by 10% relative to NRC nutritional recommendations (1994) was not shown to improve growth performance, but had beneficial effects on the metabolism and antioxidant status of the birds, as evidenced by the improvement of hepatic indices (reduction of AST and ALT activity at 9th week of life) and renal indices (reduction of UREA at 9th week of life and reduction of TP and increase level of ALB levels at 16th week of life), as well as an increase in the level of glutathione with strong antioxidant properties at 16th week of life. In comparison to the lower level of Arg in the diet, an increase in the amount of this amino acid to 105% Lys did not improve growth performance, metabolism, or antioxidant status. An Arg level of 95% Lys can be used in a diet for turkeys containing 10% more Lys than the level recommended by the NRC (1994).

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

Arginine (Arg) and lysine (Lys) may be important for the overall health of turkeys. The aim of this study was to determine whether low (consistent with the guidelines) and high (10% higher than recommended) levels of dietary Arg and Lys can modulate performance and the functional status of the gut. Female turkeys were allocated to four dietary treatments (two levels of Lys (low or high) and two levels of Arg (low or high)) for a 16 wk feeding period. The treatments did not affect turkey performance determined separately for four feeding phases and for the entire 16 wk experiment (p > 0.05). They had no significant influence on carcass yield, meat characteristics or the associated traits either (p > 0.05). High-Lys diets contributed to a decrease in cecal pH, a significant increase in the concentrations of short-chain fatty acids (SCFA) and a decrease in the concentrations of putrefactive SCFA and ammonia in the cecum. High dietary levels of both amino acids significantly enhanced the activity of cecal microbiota evaluated based on extracellular enzyme activity. These findings indicate that the higher dietary level of Lys was more effective in modulating the physiological status of the gut in turkeys than Arg.