Evaluation of Indian sheep breeds of arid zone under heat stress condition

•Heat stress effects significantly on hemato- physio-biochemical traits in sheep.•Significantly lower for Hb, PCV, Triglycerides, Cholestrol for all three breeds.•Significantly higher values for SGOT, RR, PR in afternoon hours.•Magra breed had highest overall adaptability followed by Marwari and Chokla.

The present study was conducted to assess the effect of the heat stress on the hematological and physio-biochemical parameters of sheep breeds thriving in hot and arid climatic conditions. Thirty animals (female) of about one and half year of age from each sheep breed (Chokla, Magra and Marwari) were used for the estimation of hematological and physio-biochemical parameters under normal (lower Temperature Humidity Index of 65) and heat stress condition (higher Temperature Humidity Index of 84). T test analysis revealed significantly higher values in the heat stressed condition for SGOT, respiratory rate and pulse rate in afternoon hours; and significantly lower values for Hb%, PCV%, Triglycerides and Cholestrol for all the three breeds. Magra breed of sheep had highest overall adaptability (83.29%) followed by Marwari (80.41%) and Chokla with the least adaptability (79.13). Higher overall adaptability in Magra sheep in this region might be due to the white and lustrous coat of Magra which reflects the sun light more as compared to other sheep breeds. However, the effect was found to be non-significant (P > 0.05). Therefore, it is concluded that these sheep breeds are equally adaptable to the hot and arid climatic conditions of this region.