PERFORMANCE EVALUATION OF HEAT-STRESSED BROILERS REARED IN CAGES, FED ON HIGH ENERGY AND PROTEIN DIETS SUPPLEMENTED WITH VITAMIN C AND ELECTROLYTES.
GHULAM HUSSAIN JAFFAR, JAN BLÁHA
Abstract
One day old broiler chicks were kept under acute and
constant heat stress. The chicks were divided into 4 groups. Gl was kept as
control under normal required temperature (20-35°C) whereas, G2, G3 and G4 were
reared at high ambient temperature ranging from 35 -45°C. The control group
received standard diet in both starter and finisher phases. G2 received the
same diet as that of the control under acute heat stress. G3 and G4 were fed
on high energy and protein diets supplemented with vitamin C and electrolytes
+ vitamins respectively were reared under acute heat stress conditions. Constant
high environmental temperature decreased weight gain in all the experimental
groups of birds as compared to broilers in the control group. Weight gain was
41.6%, 34.2% and 31.46% less in G2 than Gl , G3 and G4 respectively. 30% more
birds died in G2 than in the control. The mortality was 20% and 15% heigher
in G3 and G4 respectively than in the control birds. Vitamin C with high nutrient
diet showed 10% less mortality whereas, electrolyte + vitamins with same nutrients
decreased mortality by 15% with 11.12 and 14.71% more weight gain than G2 receiving
normal standard unsupplemented diet under acute constant heat stress.
Key words:
Acute heat stress, high energy and protein diets,
feed consumption, feed efficiency, weight gain, mortality, cages