Influence of environmental temperatures on some Physiological and Biochemical Parameters of New-Zealand Rabbit Males

Abstract

The physiological performance and biochemical parameters of sixteen adult New-Zealand White rabbit males of 6 months old and 2.5 ± 0.14 kg live body weight was investigated during spring and summer seasons in natural conditions. The maximum and minimum ambient temperatures were 27.1 ºC and 18.9 ºC in spring versus 32.2 ºC and 26.5 ºC in summer, while the average relative humidity was 86.1 % in spring versus 89.5 % in summer. Results showed a decrease in body weight (BW) during summer, which was accompanied with decreases in food intake and increase in water intake. Hematological values, including hemoglobin (Hb), packed cell volume (PCV) and red blood cell (RBC) counts were decreased, while white blood cell (WBC) counts were increased during summer compared with spring. Plasma total protein (TP), globulins (G), total lipids (TL) and cholesterol were increased during the summer season. Activity of some plasma enzymes indicated that there were significant decreases in alanineaminotransaminase (ALT) and alkaline phosphatase (ALP), and increases in lactate dehydrogenase (LDH) during summer compared with spring. Results suggest that exposure of New-Zealand rabbits to hot environmental conditions adversely affects physiological functions as reflected by the hematological and biochemical parameters.