Fox T W
Poult Sci. 1980 Nov;59(11):2391-6. doi: 10.3382/ps.0592391.
Adult White Plymouth Rock hens were submitted to a heat shock of 42.2 C. It was demonstrated that .1% thiouracil fed for 4 weeks prior to heat stress significantly increased survival time. Administration of DL-thyroxine administered at the rate of 4 micrograms/100 g body weight injected on day of testing did not alter survival time. However, survival under heat shock was significantly reduced if DL-thyroxine was administered daily for 3 days prior to testing. White Rocks exhibited significantly longer survival time under heat shock than Single Comb White Leghorns, and females of both breeds exhibited significantly longer survival time their male counterparts. Treatment with DL-thyroxine greatly reduced the survival time differences between breeds and sex. The implications of these findings for applied breeding programs are discussed.
成年白色普利茅斯洛克母鸡接受了42.2摄氏度的热休克处理。结果表明，在热应激前4周喂食0.1%的硫脲可显著延长存活时间。在测试当天以4微克/100克体重的剂量注射DL-甲状腺素，并未改变存活时间。然而，如果在测试前3天每天给予DL-甲状腺素，热休克下的存活率会显著降低。白色洛克鸡在热休克下的存活时间明显长于单冠白来航鸡，两个品种的雌性比雄性的存活时间都明显更长。用DL-甲状腺素处理大大减少了品种和性别之间的存活时间差异。讨论了这些发现对应用育种计划的意义。
