Lin H, De Vos D, Decuypere E, Buyse J
Department of Animal Science, Shandong Agricultural University, Shandong 271018, PR China.
Comp Biochem Physiol C Toxicol Pharmacol. 2008 Jan;147(1):30-5. doi: 10.1016/j.cbpc.2007.07.005. Epub 2007 Aug 1.
In order to evaluate the metabolic responses of laying hens induced by high temperature at later laying stage, nine 60-wk-old laying hens (Gallus gallus domesticus) were employed in the present study. The hens were exposed to 32 degrees C for 21 d and blood samples were obtained before and at 1, 7, 14 and 21 d of heat exposure. The reactive oxygen species (ROS) formed in blood during heat exposure were estimated by the ex vivo spin-trapping method. Body temperature and plasma concentrations of glucose, urate, creatine kinase (CK), triiodothyronine (T(3)), thyroxine (T(4)), corticosterone (CORT), thiobarbituric acid reacting substances (TBARS), ferric/reducing antioxidant power (FRAP) and superoxide dismutase (SOD) activity were measured. Plasma levels of glucose, CK and CORT were not significantly influenced by heat exposure at any time point. The circulating concentrations of T(3) were decreased while plasma T(4) levels changed in the opposite way. The formation of ROS was significantly augmented by heat exposure in laying hens though the body temperature was not significantly altered. The enhanced enzymatic and non-enzymatic antioxidant systems acted in concert to alleviate the heat stress evoked oxidative damage.
为了评估高温对产蛋后期蛋鸡代谢反应的影响，本研究选用了9只60周龄的蛋鸡（家鸡）。将这些母鸡置于32℃环境下21天，并在热暴露前以及热暴露第1、7、14和21天采集血样。采用体外自旋捕获法估算热暴露期间血液中形成的活性氧（ROS）。测量体温以及血浆中葡萄糖、尿酸、肌酸激酶（CK）、三碘甲状腺原氨酸（T(3)）、甲状腺素（T(4)）、皮质酮（CORT）、硫代巴比妥酸反应物质（TBARS）、铁/还原抗氧化能力（FRAP）和超氧化物歧化酶（SOD）活性。在任何时间点，热暴露均未显著影响血浆中葡萄糖、CK和CORT的水平。循环中的T(3)浓度降低，而血浆T(4)水平变化趋势相反。尽管体温未显著改变，但热暴露显著增加了蛋鸡体内ROS的形成。增强的酶促和非酶促抗氧化系统协同作用，减轻了热应激引起的氧化损伤。
