Effect of intermittent light on leg abnormalities, breast blisters and mortality in broilers

An experiment was conducted to study the effect of intermittent light on leg abnormalities, breast blisters and mortality in broilers. Four hundred day old chicks of Vencobb strain were placed randomly in eight light controlled pens of tifty each (n= 4 x 50 each). Uniform lighting schedule was given upto 21 days of age and then onwards two lighting schedule as 23 hrs light and 1 hr dark (23 L i.e. CL) and 2 hrs light and 4 hrs dark (16 L i.e. IL) were given upto 49 days. The incidence of leg abnormalities, breast blisters and mortality were calculated at 49 days of age. There was signiticant difference for leg abnormalities and breast blisters at 49 days with IL, birds having less abnormalities, whereas there was no significant ditference for mortality.

Continuous light and one hour darkness at midnight is a common lighting regime for raising broilers. The logic behind the one hour of darkness which is usually provided between midnight to 00 hrs (i.e. 11 pm - 00 hrs) is to acclimatize the birds to darkness in the event of a power failure. Now-a-days the increasing evidence from several research laboratories indicates that the performance of broilers can be improved by adopting the intermittent lighting regime instead of the continuous lighting regime (Buckland et al., 1976; Buys et al., 1998). The purpose of this experiment was to study the etlect of intermittent light on leg abnormalities, breast blisters and mortality percentage.