The study involved 600 7-day-old commercial
broiler chickens. The experiment was conducted
in 12 deep litter pens, each measuring 1.83 m x
3.05 m, giving a floor space of5.582 m2• Each pen
was used as a brooder during the first 2 weeks of
the study, and heat was supplied by means of
three 100-watt incandescent bulbs per pen.
Brooding temperatures ranged from a minimum of
27 to a maximum of 39°C. Temperature in the
poultry house after the brooding period depended
on the temperature of the outside air. The maximum
and minimum ambient temperatures recorded
during the experimental period were 37 and 23°C,
respectively. Relative humidity recorded daily
ranged from aminimum of60 to a maximum of75
per cent.