环境温度对鸡饲粮代谢能测值及血浆中甲状腺激素浓度的影响

SUBTLE EFFECT OF AMBIENT TEMPERATURE ON METABOLIZABLE ENERGY VALUES OF POULTRY'S DIETS

在5～35℃区间设6个温度条件,研究了环境温度对鸡饲粮干物质表观代谢率(ADMR)、干物质真代谢率(TDMR)、表观代谢能(AME)、真代谢能(TME)及血浆中甲状腺激素水平的影响,并探讨了干物质代谢率、内源性干物质(EDM)、内源性能量(EEL)排出量及代谢能等与血浆中甲状腺激素水平的关系。共用78只成年京白公鸡进行了测定。结果表明:环境温度显著影响ADMR、TDMR、EDM、EEL、AME、TME及血浆中三碘甲腺原氨酸(T_3)的水平。ADMR、AME、EDM、EEL、TDMR、TME、血浆中T_3浓度与环境温度的关系呈曲线型,其中EDM、EEL、TDMR用对数曲线模拟较好。本试验发现ADMR、AME、EDM、EEL、TDMR、TME与血浆中T_3浓度有极显著的相关关系,其进一步的生理机制有待深入研究。

A single factorial design with 78 adult roosters were used to study the effects of ambient temperature on apparent and true metabolizability of dry matter (ADMR, TDMR), apparent and true metabolizable energy (AME, TME) for chicken diet, excretory amounts of endogenous dry matter and energy (EMD, EEL), plasma thyroid hor-mones(T3, T4) concentration and the relationships between plasma thyroid hormones and ADMR, AME, EDM, EEL, TDMR, TME were established. Ranges of ambient temperature used for the treatment were 5~10℃, 10~15℃, 15~20℃, 20~25℃, 25~30℃, 30~ 35℃. Ambient temperature affected ADMR, AME, EDM, EEL, TDMR, TME, plasma T3 concentration significantly except plasma T4 concentration. The relationships between ambient temperature and ADMR, AME, EDM, EEL, TDMR, TME,plasma T3 concentration were curvilinear. Results also indicated that there were some relation between plasma T3 concentration and ADMR, AME, EDM, EEL, TDMR, TME. These effects need to be studied further.