Adaptive evaluation of different coat colour of Morada Nova sheep in an equatorial semiarid region

Present paper is aimed to show thermoregulatory responses of locally adapted sheep with different coat colors, in an equatorial semiarid region. There were used four groups according to the coat color: (1) dark red animals, (2) intermediate red, (3) light red, and (4) white coated animals. Animals were measured for rectal temperature (RT), skin surface temperature (ST), respiratory rate (RR), heat loss by respiratory evaporation (RE), heat exchange by convection (HC) and radiation (HR), from 1100 to 1400 hour, after the animals had stayed in a pen exposed to the sun. Results showed that all groups maintained homeothermy. The RR was higher in the animals of groups 1 to 3, which also showed higher values for ST when compared to the white coated animals. Sensible heat exchange mechanisms were not important for heat loss and HR was a significant source of heat gain by animals from the environment. Groups 1, 2 and 3 used RR in a more intense way compared to group 4. It was concluded that Morada Nova sheep has good adaptability to the semiarid environment, regardless of the coat color.