Abstract
This study was carried out on Poultry field department of animal resources-college of Agriculture and Forestry-University of Mosul for the period from 2/8/2013 to 19/9/2013 in order to study the effect of acclimation and type of added fat to alleviate the heat stress of broiler chickens reared under high temperature. Seven hundred of one day old unsexed broiler chickens (Ross 308). were division to two division, the first division reared on ordinary condition and called not acclimated and other division also reared on ordinary condition yet exposed to (37 ±2)°C temperature for six hours daily at age (5, 9, 13 and 17) day to acclimate to high temperature and called acclimated. At (22) days old birds divided into eight treatments as follows T1 reared on standard ration and acclimated, T2 reared on ration contain (4)% fat and acclimated, T3 reared on ration contain (4)% oil and acclimated, T4 reared on ration contain (2)% fat and (2)% oil and acclimated, T5 reared on standard ration and un acclimated, T6 reared on ration contain (4)% fat and un acclimated, T7 reared on ration contain (4)% oil and un acclimated, T8 reared on ration contain (2)% fat and (2)% oil and un acclimated. The house temperature have risen to rotatory temperature (25-35-25)°C and still age of marketing (49) day. Statistical Analysis of data showed Significantly increase in live body weight for T3 and T5. Significantly decrease in mortality rate for T3 and T5, rectal temperature for treatment of using oil, fat and mixed, packed call volume, glucose concentrate cholesterol concentrate, H/L cell for treating of using oil and mixture. No Significantly differences in weight gain, feed consumption, feed conversion ratio, dressing percentage, relative weight of breast, total protean, albumin, globulin concentrate in blood serum, also the histological study revealed the absence of any passive effect on the histological picture of intestine.
