22 May 1998

Reduce daylength

REDUCING daylight hours can help cut broiler mortality and gait abnormalities, and lift profits.

While many producers run broiler houses under a 23-hour daylight/one-hour darkness system, adopting an eight- or even 16-hour day would be better, according to ADASs Andrew Walker.

"Trials found that reducing daylength to eight hours, giving birds opportunity for a proper rest period, between five days old and sale reduced mortality by 50%. Flip-overs, where birds are found lying on their backs due to heart failure, were significantly reduced. Cutting day length also reduced culling due to gait abnormalities."

Although producers use 23-hour daylight to maximise growth, shorter day length improved margin of liveweight value less feed costs, as more birds survive to sale time.

"Feed conversion efficiency was not affected to 45 days, so it is still possible to produce a marketable bird within the current time cycle."