Heat stress is one of the main factors which adversely affecting the animal welfare and thus the economic benefits of the
farms. Goat husbandry in Egypt tends to breed throughout the year. However, a high ambient temperature is the major
restriction on the animal productivity. This effect is provoked when heat stress is accompanied by high ambient humidity.
This study was aimed to study the effect of heat stress on the physiological, some hematological and biochemical
parameters. Twenty-five goats were exposed to the daytime (30 days) after an initial 7 day shading period, while another
10 goats were exposed to the shading regimen throughout the entire 30 days as a control group. Heat stressed goats
showed the decrease of the feed intake, body weight and growth rate. Physiologically, the rectal temperature, respiration
and heart rates were observed to be significantly higher. Moreover, the red blood cells count (RBCs), hemoglobin
concentration (Hb), and packed cell volume (PCV) were significantly increased, whereas an insignificant change in white
blood cells count (WBCs). Also, the serum total proteins, albumin, glucose, urea and creatinine levels were significantly
decreased. On the other hand, cortisol level were significantly increased in heat stressed goats. Our results indicated that
heat stress produced a significant alteration in the physiological, some hematological and biochemical parameters