Saito Shin, Tachibana Tetsuya, Choi Yang-Ho, Denbow D Michael, Furuse Mitsuhiro
Laboratory of Advanced Animal and Marine Bioresources, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan.
Comp Biochem Physiol A Mol Integr Physiol. 2005 Jul;141(3):305-9. doi: 10.1016/j.cbpb.2005.05.054.
The present study compared the plasma corticosterone concentrations between meat- and layer-type neonatal chicks (Gallus gallus) (1) exposed to isolation-induced stress or (2) injected intracerebroventricularly (ICV) with corticotropin-releasing factor (CRF). Both types of neonatal chicks housed in groups were individually introduced to an open field arena and locomotion and distress-induced vocalizations were monitored for 10 min. The responses of the two strains were remarkably different, with meat-type chicks being less active than layer-type chicks. Distress-induced vocalizations were drastically decreased over time in meat-type chicks while they remained high in layer-type chicks throughout the test. Plasma corticosterone concentrations measured at the end of the test were significantly higher in layer-type chicks than in meat-type ones. Plasma corticosterone concentrations measured 10 min after the ICV injection of CRF were significantly higher in layer- than meat-type chicks. These results indicate that meat-type chicks have either a greater capability to acclimatize to novel environments, or a blunted HPA axis compared with layer-type chicks.
本研究比较了肉用型和蛋用型新生雏鸡（原鸡）在以下两种情况下的血浆皮质酮浓度：（1）暴露于隔离诱导的应激中；（2）脑室内注射促肾上腺皮质激素释放因子（CRF）。将两组饲养的两种新生雏鸡分别放入旷场实验场地，监测其运动情况和应激诱导的鸣叫，持续10分钟。两种品系的反应显著不同，肉用型雏鸡比蛋用型雏鸡活跃度低。肉用型雏鸡因应激诱导的鸣叫随时间急剧减少，而在整个测试过程中，蛋用型雏鸡的鸣叫一直保持在较高水平。测试结束时测得的蛋用型雏鸡血浆皮质酮浓度显著高于肉用型雏鸡。脑室内注射CRF 10分钟后测得的血浆皮质酮浓度，蛋用型雏鸡显著高于肉用型雏鸡。这些结果表明，与蛋用型雏鸡相比，肉用型雏鸡要么具有更强的适应新环境的能力，要么其下丘脑-垂体-肾上腺（HPA）轴反应迟钝。
