Dietary supplementation with glutamine and γ ‐aminobutyric acid improves growth performance and serum parameters in 22‐ to 35‐day‐old broilers exposed to hot environment

作者：Hong Hu, Xi Bai, Assar Ali Shah, A. Y. Wen, J.L. Hua, C. Y. Che, Shaojun He, Jinpeng Jiang, Zuonan Cai, Sifa Dai · 发表于：Journal of Animal Physiology and Animal Nutrition · 年份：2015 · DOI：10.1111/jpn.12346 · 被引用次数：42 · 研究领域：Animal Nutrition and Physiology、GABA and Rice Research、Biochemical effects in animals

This study was designed using 360 21-day-old chicks to determine the influences of diet supplementation with glutamine (5 g/kg), γ-aminobutyric acid (GABA, 100 mg/kg) or their combinations on performance and serum parameters exposed to cycling high temperatures. From 22 to 35 days, the experimental groups (2 × 2) were subjected to circular heat stress by exposing them to 30-34 °C cycling, while the positive control group was exposed to 23 °C constant. The blood of broilers was collected to detect serum parameters on days 28 and 35. Compared with the positive control group, the cycling high temperature decreased (p < 0.05) the feed consumption, weight gain and serum total protein (TP), glucose, thyroxine (T4), insulin, alkaline phosphatase (ALP), glutamine, GABA and glutamate levels, while increased (p < 0.05) the serum triglyceride (TG), corticosterone (CS), glucagon (GN), creatine kinase (CK), glutamic oxaloacetic transaminase (GOT), nitric oxide synthase (NOS), glutamate pyruvate transaminase (GPT) and lactate dehydrogenase (LDH) levels during 22-35 days. However, dietary glutamine (5 g/kg) increased (p < 0.05) the feed consumption, weight gain and serum levels of glutamine, TP, insulin and ALP, but decreased (p < 0.05) the serum TG, CK, GOT, NOS and GPT levels. Diet supplemented with GABA also increased (p < 0.05) weight gain and the serum levels of TP, T4, ALP, GABA and glutamine. In addition, the significant interactions (p < 0.05) between glutamine and GABA were found i...