ADAPTIVITY OF BUFFALO CALVES TO DIFFER THERMAL CONDITIONS

Abstract

Eight buffalo male calves, aged 6 months and average range weighed 118.00±2.6 - 119.25±2.2 kg were used in this study. The calves were divided into 2 comparative groups (A and B) with 4 calves each. The calves were exposed to either artificial constant severe heat stress (Lab A, 40°C) or comfort (Lab B, 25°C) for one month. The calves in both groups were then exposed to15 days period of natural climatic outdoors conditions. Thereafter the animals returned back to the same artificial condition. The average body weight at the end of exposure to heat stress before slaughter was 106.8±2.3 for calves in group A and 167.0±3.2 in group B (at 9 months of age). The calves have fasted for 19 hours before slaughter. After slaughter, the skin was weighted. Then the skin samples were taken from the neck, abdomen, and back regions divided into 2 parts. One part was used to study the number of hairs by haircuts, weighed. And the counts relative to weight were determined. The development of acts in skin structure in response to the heat-regulating mechanism was also studied. The relationship between histological parameters (length, density, the efficiency of the tensor muscle of hair, the thickness of skin, number of sweat glands, and number of sebaceous glands), as well as the efficiency of buffalo under heat stress circumstances was also studied. The results indicated that the skin of an animal plays an important role in adapting the animal under various conditions. A high correlation (r= 0.93, P ≤ 0.01) was found between animal body weight and skin weight in group B. The correlation with hair in group A was medium and negative (r= -0.55, P ≤0.01). The buffalo can change both the morphology and histology of their skin to maintain biological processes within normal limits. Buffalo calves have the ability to modify their skin trout's to cope with a wide variety of thermal conditions. This modification includes changes in skin thickness, hair length, number of hair follicles, and hair color. The great adaptive potentiality of buffalo to heat stress condition makes the animals of choice to live successfully under the circumstances of the upcoming climatic change