We examined the effects of oral administration of L-citrulline (L-Cit) on plasma metabolic hormones and biochemical profile in broilers. Food intake, water intake, and body temperature were also analyzed. After dual oral administration (20 mmol/head/administration) of L-Cit, broilers were exposed to a high ambient temperature (HT; 30 ± 1°C) chamber for 120 min. Oral administration of L-Cit reduced (p < .001) rectal temperature in broilers. Food intake was increased (p < .05) by heat stress, but it was reduced (p < .05) by L-Cit. Plasma levels of 3,5,3′-triiodothyronine, which initially increased (p < .0001) due to heat stress, were reduced (p < .01) by oral administration of L-Cit. Plasma insulin levels were increased by heat exposure (p < .01) and oral L-Cit (p < .05). Heat stress caused a decline (p < .05) in plasma thyroxine. Plasma lactic acid (p < .05) and non-esterified fatty acids (p < .01) were increased in L-Cit-treated heat-exposed broilers. In conclusion, our results suggest that oral L-Cit can modulate plasma concentrations of major metabolic hormones and reduces food intake in broilers.

中文翻译：

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口服 L-瓜氨酸可改变热暴露肉鸡的血浆激素浓度和生化特征

我们研究了口服 L-瓜氨酸 (L-Cit) 对肉鸡血浆代谢激素和生化特征的影响。还分析了食物摄入量、水摄入量和体温。在 L-Cit 双重口服给药（20 毫摩尔/头/给药）后，将肉鸡暴露在高环境温度（HT；30 ± 1°C）室中 120 分钟。口服 L-Cit 可降低 ( p  < .001) 肉鸡的直肠温度。食物摄入量因热应激而增加 ( p < .05)，但因 L-Cit 而 减少 ( p < .05)。3,5,3'-三碘甲腺原氨酸的血浆水平最初 因热应激而升高 ( p < .0001)，但随后降低 ( p < .01) 口服 L-Cit。热暴露 ( p  < .01) 和口服 L-Cit ( p  < .05) 会增加血浆胰岛素水平。 热应激导致血浆甲状腺素下降 ( p < .05)。L-Cit 处理的热暴露肉鸡的血浆乳酸 ( p  < .05) 和非酯化脂肪酸 ( p  < .01) 增加。总之，我们的结果表明口服 L-Cit 可以调节主要代谢激素的血浆浓度并减少肉鸡的食物摄入量。