Effects of Sodium Salicylate on Thyroid Function in Heat-Stressed Chickens

Abstract

BIRDS subjected to high environmental temperatures exhibit numerous adverse effects which include: a decrease in body weight (Huston et al., 1957), a decrease in feed consumption (Joiner and Huston, 1957), an increase in body temperature (Wilson, 1948), a decrease in egg production (Turner et al., 1946) and a decrease in both thyroid weight (Hoffman and Shaffner, 1950) and activity (Dempsey and Astwood, 1943). Of these adverse effects, it is probable that the increase in body temperature and decrease in thyroid activity are primary changes which are responsible in large part for the decrease in body weight, decrease in feed consumption and decrease in egg production. It has been shown in mammals (Dempsey and Astwood, 1943) and birds (Heninger et al., 1960) that a reciprocal relationship exists between environmental temperature (and to a lesser extent, body temperature) and thyorid activity. Although thyroid activity has been shown to decrease in birds at …