Vol. 8, Issue 10, Part B (2024)

Vechur, an indigenous cattle breed from Kerala is well known for its adaptability to local environmental conditions, including notable heat tolerance. The present study was done to see the effect of heat stress on blood parameters in Vechur cattle of similar age groups (12-14 months of age) and physiological status. Blood samples were collected and analyzed based on the temperature-humidity index (THI). Blood samples were collected and analyzed for haemoglobin, volume of packed red cells, red blood cell count, white blood cell count and blood pH. A significant rise (p<0.01) in physiological parameters such as respiration rate and surface body temperature was observed. Biochemical parameters such as total protein, cholesterol, AST and ALT and hormonal parameters such as T₃, T₄ and cortisol showed significant differences (p<0.01) during heat stress. From the present study, it can be concluded that THI is a sensitive indicator of heat stress.