Egg production response of laying chickens to feather clipping, cool water and aspirin during hot weather conditions.

An 8-week trial was conducted between March and May (hot-dry season) to determine effects of water temperature, feather clipping and aspirin on egg production of chickens. The treatments tested were hens given ordinary drinking water (control), cool water (100 g ice block per L) and aspirin (0.3 mg per L of ordinary water) and hens whose feathers were clipped (about two thirds of body feathers clipped). At 32 weeks of age, 120 Lohmann brown layer chickens of similar live weights were randomly divided into 12 groups of ten hens each and assigned to the treatments in triplicate using a completely randomized design. Feed and water were given ad libitum. Data included feed intake, water consumption, hen-day egg production and egg weight. Ambient house temperature, hen's cloacal temperature and water temperature were monitored daily during the experimental period. Mean daily ambient temperature increased from 28.4 to 35.0 °C during the study period with consequent increase in cloacal temperatures (40.31 to 41.18 °C) of hens, ordinary drinking water and cool water. None of the treatments had any significant (P > 0.05) effects on feed intake and water consumption of the birds. Hens given cool water produced more (P < 0.05) eggs and better (P < 0.05) feed efficiency than hens assigned to other treatments. Mean egg weight of each treatment was similar (P > 0.05). It is concluded that the provision of cool water in a hot-dry climate had a beneficial effect on egg laying performance of chickens.