Impact of heat stress on growth and egg quality of poultry birds

Abstract

Poultry farming is fast growing business in India with quick and regular return. These birds are very sensitive to environmental changes which directly or indirectly affect the production and reproduction performance of the birds. Heat stress is one of the most important environmental stressors challenging poultry production worldwide. Heat stress affects directly and indirectly metabolic and physiological acclimation which may reduce the growth and egg quality of commercial laying hens. This study was conducted to evaluate the drastic effects of swear heat conditions. In this experiment total 54 chicks of breeds i.e. Rhode Island Red, Punjab Red and Kadaknath were housed in cages in each of 3 environmental chambers. This study includes three treatments along with twice replicates and each replicate consists of 18 birds. The treatments consists of control (average temperature (22.5 oC) and relative humidity (50%), cyclic (daily cyclic temperature (22.5-37 oC) and humidity (50-15%) and heat stress (constant heat (37 oC) and humidity (50%) for 5 wk. Standard feeding and management practices were followed during the experimental period. Different growth and egg quality parameters were measured. Body weight and feed consumption were significantly reduced in all three breeds in the heat stress group. Egg production, egg weight, shell weight and shell thickness were significantly inhibited among birds in the heat stress group. These results indicate that heat stress not only adversely affects production performance but also inhibits egg quality.