TY - JOUR
T1 - L-Leucine increases the daily body temperature and affords thermotolerance in broiler chicks
AU - Han, Guofeng
AU - Yang, Hui
AU - Wang, Yunhao
AU - Haraguchi, Shogo
AU - Miyazaki, Takuro
AU - Bungo, Takashi
AU - Tashiro, Kosuke
AU - Furuse, Mitsuhiro
AU - Chowdhury, Vishwajit S.
N1 - Funding Information:
This study was supported by JSPS KAKENHI Grant Numbers JP15K07694 and JP18K19271 to VSC and JP17KT0077 to TB.
Publisher Copyright:
© 2019 by Asian-Australasian Journal of Animal Sciences.
PY - 2019/6
Y1 - 2019/6
N2 - Objective: Heat stress poses an increasing threat for poultry production. Some amino acids have been found to play critical roles in affording thermotolerance. Recently, it was found that in ovo administration of L-leucine (L-Leu) altered amino acid metabolism and afforded thermotolerance in heat-exposed broiler chicks. Methods: In this study, two doses (35 and 70 μmol/egg) of L-Leu were administered in ovo on embryonic day 7 to determine their effect on rectal temperature (RT), body weight (BW) and thyroid hormones at hatching. Changes in RT, BW, and thermotolerance in post-hatched chicks were also analyzed. Results: It was found that in ovo administration of L-Leu dose-dependently reduced RT and plasma thyroxine (T4) level just after hatching. In post-hatched neonatal broiler chicks, however, the higher dose of L-Leu administered in ovo significantly increased RT without affecting BW gain. In chicks that had been exposed to heat stress, the RT was significantly lowered by in ovo administration of L-Leu (high dose) in comparison with the control chicks under the same high ambient temperature (HT: 35°C±1°C, 120 min). Conclusion: In ovo administration of L-Leu in a high dose contributed to an increased daily body temperature and afforded thermotolerance under HT in neonatal broiler chicks.
AB - Objective: Heat stress poses an increasing threat for poultry production. Some amino acids have been found to play critical roles in affording thermotolerance. Recently, it was found that in ovo administration of L-leucine (L-Leu) altered amino acid metabolism and afforded thermotolerance in heat-exposed broiler chicks. Methods: In this study, two doses (35 and 70 μmol/egg) of L-Leu were administered in ovo on embryonic day 7 to determine their effect on rectal temperature (RT), body weight (BW) and thyroid hormones at hatching. Changes in RT, BW, and thermotolerance in post-hatched chicks were also analyzed. Results: It was found that in ovo administration of L-Leu dose-dependently reduced RT and plasma thyroxine (T4) level just after hatching. In post-hatched neonatal broiler chicks, however, the higher dose of L-Leu administered in ovo significantly increased RT without affecting BW gain. In chicks that had been exposed to heat stress, the RT was significantly lowered by in ovo administration of L-Leu (high dose) in comparison with the control chicks under the same high ambient temperature (HT: 35°C±1°C, 120 min). Conclusion: In ovo administration of L-Leu in a high dose contributed to an increased daily body temperature and afforded thermotolerance under HT in neonatal broiler chicks.
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U2 - 10.5713/ajas.18.0677
DO - 10.5713/ajas.18.0677
M3 - Article
AN - SCOPUS:85070576914
VL - 32
SP - 842
EP - 848
JO - Asian-Australasian Journal of Animal Sciences
JF - Asian-Australasian Journal of Animal Sciences
SN - 1011-2367
IS - 6
ER -