Genotype-Sex Interaction in Relation to Heat Tolerance Attributes of Pure and Crossbred Chicken Progenies

The study was carried out to evaluate the genotype-sex interaction in relation to heat toleranceattribute of pure and crossbred chicken progenies in a 12-week study. A total of twohundred and seventy two chickens were used for this study. These consisted of 150purebred chickens consisting of Isa Brown, Fulani Ecotype,Naked Neck, Normal Feather and Frizzled Feather; and 122 crossbred comprising, NN x IB, FF x IB, IB x NF and IB x FE progenies. Under natural heat stress environment genotype were significantly (P<0.05) affected by rectal temperature, pulse rate and respiratory rate. The Isa Brown had the highest value of rectal temperature (41.74oC), respiratory rate (56.76 breath/min), pulse rate (56.83beat/min) while normal feather obtained the lowest values of these traits. Crossbred of FF x IB had the highest value of rectal temperature, respiratory and pulse rates of 41.75oC,58.67 breath/min and 54.49beat/min respectively. Significant (P<0.05) effect was obtained among the sexes of pure and crossbred chicken progenies in response to heat tolerance trait, with female chickens of pure and crossbred progenies had higher responsesto heat tolerance attributes than their female counterparts. It can be concluded that Isa brown chickens were more stress among the pure and FF x IB among the crossbred with female chickens due to their physiological activities. Keywords: Heat tolerance, Genotype, sex, local chickens, exotic birds, crossbred progenie