Effects of Heat Stress on Some Blood Parameters in Broilers

Abstract

The purpose of the present study was to determine the effects of acute heat stress on the proportions of leucocyte components and hematocrit values in broiler chickens. Exposure of broiler chickens to 39±1 °C for 2 h at 44 d of age caused an increase in rectal temperatures, and in heterophil and basophil ratios. The H/L ratio also increased from 0.25 to 0.43. The exposure of the broilers to acute heat stress resulted in decreased monocyte and lymphocyte proportions whereas the proportion of eosinophil and the hematocrit values were not affected. It was concluded that a temperature high enough to cause increased body temperature also changes circulating leucocyte components in broilers.