Abstract:
The present study was planned to study the performance and potential profitability of four commercial
broiler strains in two different temperature zones i.e., thermoneutral zone (TN) and high ambient
temperature zone (HAT) group. Day-old broiler chicks (n=242) of four different commercial strains (Ross,
Hubbard, Cobb and Arber Acer) were placed in brooding room for the first two weeks and then chicks were
divided into two groups: TN and HAT. Chicks in TN group were housed at constant room temperature
(25ºC ± 2ºC and RH 65 ±5%) while chicks in HAT group were kept at high ambient temperature. In the
TN zone, significantly (P< 0.05) higher feed intake and weight gain were recorded on day 21, 28, 35 and
42. Feed intake in TN zone was 3.02, 9.79, 9.74 and 12.14 % higher than feed intake recorded on the
corresponding days in HAT while weight gain in thermoneutral zone was 9.28, 15.25, 17.48, and 15.62 %
higher than weight gain recorded on the corresponding days in HAT. On day 21, 28, 35 and 42 significantly
(P<0.05) lower (good) FCR was recorded in TN zone as compared to HAT zone. Higher mortality was
recorded in HAT zone as compared to thermoneutral zone. Significantly (P< 0.05) higher net return per
chick was recorded in TN zone as compared to HAT zone. Ross and Arber Acer performed better in
terms of feed intake, weight gain, FCR and are more economical to be reared in hot summer season
in tropical climates of Pakistan, while Cobb and Hubbard strains performed better in TN environment.