Effects of initial and second periods of fasting on heterophil/lymphocyte ratios and body weight.

Chickens that had never been without food or water were subjected to feed deprivation of 2 days duration on successive weeks. Both periods of feed deprivation resulted in similar reductions in body weight. The first period of feed deprivation resulted in a much more severe heterophil/lymphocyte ratio response to stress than the second period of feed deprivation. When the initial fast was followed 1 week later by 2 days of water deprivation, the heterophil/lymphocyte ratio response was similar to that of a similar flock of chickens that did not fast before the period of water deprivation.