el-Gendy E, Washburn K W
Department of Poultry Science, University of Georgia, Athens 30602-2772, USA.
Poult Sci. 1995 Feb;74(2):225-30. doi: 10.3382/ps.0740225.
Genetic variation in body temperature of broilers and its response to short-term acute (43.5 C for 45 min) heat stress was studied. Body temperatures before (T0) and after (T45) heat exposure were recorded and the changes in body temperature (T delta) were calculated for 5-wk-old chicks from 32 broiler sire families. The T0 data were utilized to rank the families as to their relative body temperature and used to conduct a one-generation divergent family selection program for high basal body temperature (H-BT) and low basal body temperature (L-BT). A control (C) line was established by random selection from the nonselected birds. There was little genetic variation in the base broiler population for body temperature, and one generation of selection for divergence in T0 did not result in differences. There were also no differences among lines in T45. Low realized heritability estimates of .09 and .17 were obtained for T0 in the L-BT and H-BT lines. Phenotypic correlations between body temperature and body weight were very low for all groups. Highly significant negative correlations were observed between T0 and T delta after heat exposure. The T0 fluctuated during the course of each day and between days. The adjustment of the data to eliminate this variation did not result in increased heritability estimates.
研究了肉鸡体温的遗传变异及其对短期急性（43.5℃，持续45分钟）热应激的反应。记录了32个肉鸡父系家系5周龄雏鸡热暴露前（T0）和热暴露后（T45）的体温，并计算了体温变化（Tδ）。利用T0数据对家系按相对体温进行排名，并用于开展一代高基础体温（H-BT）和低基础体温（L-BT）的差异家系选择程序。通过从未被选择的鸡中随机选择建立了一个对照（C）系。基础肉鸡群体中体温的遗传变异很小，对T0进行一代差异选择并未产生差异。T45在各品系间也没有差异。L-BT系和H-BT系中T0的狭义遗传力估计值较低，分别为0.09和0.17。所有组体温与体重之间的表型相关性都很低。热暴露后T0与Tδ之间观察到高度显著的负相关。T0在每天的过程中以及不同天数之间都有波动。对数据进行调整以消除这种变异并没有提高遗传力估计值。
