<b>Effect of environmental temperature on tyroid hormones, body temperature and feathering of female broilers of different genotips</b> - DOI: 10.4025/actascianimsci.v27i3.1216

Abstract

Three hundred and sixty female broilers, Cobb – 500 and ISA – Label JA 57 were raised under cold, neutral and hot temperatures in a complete randomized design with 3 x 2 factorial scheme (3 temperatures and 2 strains), with 8 repetitions to evaluate plasmatic levels of Thyroxyne (T₄) and Triiodothyronine (T₃), body temperature and feathering birds. On hot temperature there was a decrease in T₃ levels at 21, 35 and 42 days old and an increase in T4 levels at 21 days old. There was a decrease in the total feathering, in chest, wings and abdomen and an increase in superficial and body temperature. Female broilers ISA Label had better feathering, however lowest superficial temperature, average superficial temperature and body temperature. Environmental temperature affects the feathering of fast growing female broilers, that have low hot tolerance shown through the biggest body temperature. Hormonal levels of T₃ and T₄ were affected by environmental temperature