Nguyen Linh T N, Eltahan Hatem M, Pham Cuong V, Han Guofeng, Chowdhury Vishwajit S, Furuse Mitsuhiro
Laboratory of Regulation in Metabolism and Behavior, Graduate School of Bioresource and Bioenvironmental Science, Kyushu University, Fukuoka 819-0395, Japan.
Laboratory of Stress Physiology and Metabolism, Division for Experimental Natural Science, Faculty of Arts and Science, Kyushu University, Fukuoka 819-0395, Japan.
J Poult Sci. 2020 Jan 25;57(1):37-44. doi: 10.2141/jpsa.0190054.
Oral administration of l-citrulline (l-Cit) caused hypothermia, but l-Cit is not recommended in poultry diets in Japan. Watermelon is a natural source of l-Cit. The objective of this study is to examine the effect of watermelon waste, i.e., watermelon rind (WR) on the body temperature and plasma free amino acids of chicks. In Experiment 1, 14-day-old chicks were subjected to acute oral administration of WR extract (WRE) (2 m) under control thermoneutral temperature (CT). In Experiment 2, 15-day-old chicks were orally administered 1.6 m of either WRE, lowdose l-Cit (7.5 mmol/10 m), or high-dose l-Cit (15 mmol/10 m) under CT. In both experiments, rectal temperature (RT) and plasma free amino acids were analyzed. In Experiment 3, after dual oral administration of (1.6 m) WRE or l-Cit (15 mmol/10 m), 15-day-old chicks were exposed to high ambient temperature (HT; 35±1°C, 2 h) to monitor changes in RT. Acute oral administration of WRE significantly reduced RT under CT. The degree of RT reduction by WRE was similar to that by high l-Cit. Moreover, RT was significantly low at HT owing to the oral administration of WRE. However, the reduced RT was difficult to explain by the content of Cit in WRE alone. In conclusion, WRE could be used as a dietary ingredient to reduce body temperature for imparting thermotolerance in chicks.
口服L-瓜氨酸（L-Cit）会导致体温过低，但在日本的家禽日粮中不推荐使用L-Cit。西瓜是L-Cit的天然来源。本研究的目的是研究西瓜废弃物，即西瓜皮（WR）对雏鸡体温和血浆游离氨基酸的影响。在实验1中，14日龄雏鸡在控制的热中性温度（CT）下急性口服WR提取物（WRE）（2 m）。在实验2中，15日龄雏鸡在CT下口服1.6 m的WRE、低剂量L-Cit（7.5 mmol/10 m）或高剂量L-Cit（15 mmol/10 m）。在两个实验中，均分析直肠温度（RT）和血浆游离氨基酸。在实验3中，15日龄雏鸡在双重口服（1.6 m）WRE或L-Cit（15 mmol/10 m）后，暴露于高温环境（HT；35±1°C，2小时）以监测RT的变化。急性口服WRE在CT下显著降低了RT。WRE降低RT的程度与高剂量L-Cit相似。此外，由于口服WRE，HT时RT显著降低。然而，仅靠WRE中瓜氨酸的含量难以解释RT的降低。总之，WRE可作为一种日粮成分来降低体温，从而赋予雏鸡耐热性。
