Kohne H J, Jones J E
Poult Sci. 1976 Jan;55(1):277-85. doi: 10.3382/ps.0550277.
Turkey hens were exposed to stepwise increases in ambient temperature from 21degreesC. to 25degreesC. to 30degreesC. to 35degreesC. at two-week intervals. Dietary calcium levels of 1.54, 2.01 and 2.48% were fed. Production data and circulating levels of estrone, estradiol-17-beta, corticosterone, total calcium, bound calcium, and unbound calcium were studied. The dietary calcium levels had no significant influence on any of the results. The temperature increase caused a significant (P less than .05) decrease in plasma levels of calcium and estrone, egg production, shell thickness and egg weight. The temperature increase caused a significant (P less than .05) fluctuation in plasma corticosterone levels but had no apparent effect on the plasma estradiol levels. With the temperature increase, unbound plasma calcium levels and plasma corticosterone levels showed a significant (R greater than or equal to 0.50, P less than 0. less than .01) positive correlation to egg production.
将火鸡母鸡每隔两周暴露于环境温度从21摄氏度逐步升高到25摄氏度、再到30摄氏度、最后到35摄氏度的环境中。分别饲喂钙含量为1.54%、2.01%和2.48%的日粮。研究了生产数据以及雌酮、雌二醇-17-β、皮质酮、总钙、结合钙和非结合钙的循环水平。日粮钙水平对任何结果均无显著影响。温度升高导致血浆钙和雌酮水平、产蛋量、蛋壳厚度和蛋重显著（P<0.05）下降。温度升高导致血浆皮质酮水平出现显著（P<0.05）波动，但对血浆雌二醇水平无明显影响。随着温度升高，血浆非结合钙水平和血浆皮质酮水平与产蛋量呈显著（R≥0.50，P<0.01）正相关。
