changes in body temperature, respiration, heart rate and certain serum biochemical parameters of sheep during summer heat stress in jiroft

background: sheep are a form of investment and a quickly liquidatable resource, particularly in traditional and low income production systems. tropical and long warm-season regions always affect sheep production negatively. methods: in this experiment 15 female and 7 male sheep were chosen and their body temperature, heart rate, respiration rate measurements and blood sample for biochemical parameters analysis were taken during may 5 to september 5. results: heart rate and respiration rate in male sheep were a little higher compared with female sheep but there was no significant difference between them respiration (56 vs. 55) and beat (120 vs. 118 per min). rectal temperature wasn’t significant between two sexes (40.6-40.09 c˚). also skin temperature wasn’t significantly different between two sexes (36.02- 36.08 c˚). the only difference was related to month effect (p0.05). blood sodium concentration was significantly different between two sexes so that male sheep had the highest minimum average (p0.05). conclusions: these results indicated that sheep of this region had been well adapted to summer heat stress and they showed usual changes of blood metabolites in response to heat stress.