Comparative efficacy of different supplements with drinking water used to alleviate body temperature of heat-stressed broiler chickens

الملخص EN

A total of 425 one day old, unsexed, Hubbard classic broiler chicks strain were reared on floor for 6 weeks (WK) to evaluate the efficacy of different supplements to reduce body temperature (Tb) of heat-stressed broiler chickens.

Birds were given water and diet ad libitum.

At 21 day of age, 375 birds were almost equal weights chosen, randomly divided into 5 groups, 3 replicates of 25 birds each.

Treatment groups were; without supplementation (T1,control), supplementation 400 (T2) and 550 (T3) mg betaine / liter drinking water (DK), mixture of KCl, NaHCO3,vitamin C and salicylic acid by 450, 450, 50 and 50 mg / liter DK respectively (T4) and 150 mg vitamin C / liter DK (T5).

Temperature and relative humidity were recorded in 600, 1400, 1800 and 2400 hours daily.

Birds were received 24 hours light a day, also all routine management and medications were applied.

Results revealed that in most treatment groups, Tb was significantly (P < 0.01) increased in hot period of the day (1400h and 1800h) in comparison with moderate period (600h and 2400h) and the difference was higher in control treatment1 group (T1) at 4, 5, 6 WK of age and their average.

A significant (P < 0.05) decrease was found in Tb of T5 in comparison with T1 during all times of the day, whereas occurred only during hot period (1400h and 1800h) in T2, T3 and T4 at 4, 5, 6 WK of age and their average.

The average of Tb of all treatment groups for 4, 5, and 2 WK of age illustrated a significant decrease in moderate (P < 0.05) and hot periods of the day (P < 0.01) in comparison with T1, in addition to temperature difference was greater in hot period than moderate period.

It can be concluded that all supplements used in this trial, expressed their efficacy in reducing Tb of heat-stressed birds, in particular during hot period of the day, however vitamin C was the most potent.