Growth-Associated Traits in Parental and F1 Populations of Chickens Under Different Feeding Programs

In two experiments, parental populations of chickens and their F1 crosses were fed ad libitum or on alternate days. Eating and drinking behaviors, ability to compensate for fasting, and surface and cloacal temperatures were measured. Genetic and environmental (due to fasting) differences in feeding and drinking behaviors were found. Chicks from lines selected for larger body weight were better able to compensate for a 24-hr fast than those selected for smaller weight. Crosses were similar to the parental line that was the better compensator. Correlations between surface temperatures and body weights were consistently positive.