KARACHI - A study, conducted by Karachi University (KU), reveals that weight and production of commercial layers' eggs can be increased if such chickens are provided feasible low temperature in their environmentally controlled houses. Environmental temperature effects on the feed intake, egg production and egg weight of commercial layers. The study was conducted by the poultry unit of the department of physiology at KU. Lecturer Zulfiqar Ahmed and Professor Farhat Zafar conducted the research under the supervision of Dr A A Qureshi in collaboration with K&N's Poultry Research Institute, Karachi. Talking to The Nation on Sunday, Zulfiqar Ahmed said that more than 90 per cent of chickens were kept in the scattered open houses with Asbestos, tin sheets and thatched roof, in spite of the fact that the climate was extremely hot or cold. Because of this reason, birds should be housed in such a place where environment will enable them to maintain their thermal balance and yield optimum production. The body temperature of the chickens rises as the ambient temperature rises but the environment helps the bird to loose body heat equal to the heat produced," he said. Karachi has nearly 300 commercial egg layers poultry farms with a capacity variation of 3,000 to 10,000 layers kept in cages under the thatched roof and concrete buildings, he said, adding that that a drop in egg production was a serious problem faced by most of the farmers who did not have any environmentally controlled houses except some having locally improved cooling systems. He said, "These systems are designed on the basis of evaporative cooling but Karachi being a sea port, has always a high humidity during summer. Consequently evaporative cooling systems do not provide any relief to the birds as excessive water vapors continue to cause distress to the birds. This study was carried out at a commercial farm having a flock of 3000 commercial layer under a roof with asbestos, automatic drinkers and manual feeders. The water was given at lib but feed was calculated on the basis of breed specified quantity once a day. Daily record was maintained of feed intake, egg production, egg weight and temperature since 21 5t week of age till 44th week. On the basis of statistical analysis it was concluded that the increase of house temperature significantly decreases the feed intake and egg production but increased house temperature showed non significant relationship with egg weight." To a query, he said that in winter the feed intakes of such birds have been increased that was why layers' eggs in the winter period were sold on the high prices.