The aim of this work was to evaluate physical aspects of heat tolerance in cattle. Sixty-four animals from five naturalized breeds were used, including Curraleiro (15 animals), Mocho Nacional (7), Crioulo Lageano (17), Pantaneira (14) and Junqueira (11), as well as twenty-six animals from two commercial breeds: Nellore (15) and Holstein (11). Measurements on shoulder height, girth, body length, cannon bone circumference, skin and hair thickness were analysed as well as hair density and hair and skin pigmentation. Girth in Curraleiro was significantly smaller than in other breeds, especially Mocho Nacional. Crioulo Lageano and Pantaneira had the thickest hair and Mocho Nacional the thickest skin. Curraleiro and Junqueira were shown to be the most heat tolerant of the naturalized breeds.
adaptation; bioclimatology; body measurements; heat tolerance
