Electrolyte and ascorbic acid supplementation for heat exposed broilers in Thailand

Abstract

The objective of this study was to compare the effects of ascorbic acid and mixed electrolytes on growth performance, ammonia emission and serum antioxidant enzyme activity in broilers during summer period. Two hundred and ten male and female Arbor Acre broilers during grower-finisher period (22-42 days old) were allocated into 3 groups with different additives in drinking water: 1,000 ppm ascorbic acid (T1); 2,000 ppm mixed electrolytes containing only Na+, K+ and HCO3- (T2) and none (T3 serving as control group). The experiment was conducted in an open broiler house during the summer period between April and May. Results indicated that there were no significant differences in broiler performance among the treatments. The control group (T3) had slightly higher mortality rate compared to the others. There was no significant difference among the groups in ammonia concentration and litter moisture in all weeks. The broilers in T1 (ascorbic acid) had significantly higher glutathione peroxidase (GPx) enzyme and lower MDA levels (p<0.05) compared with the other groups. Osmolarity values of the broilers at 4 weeks were low in all groups and the broilers in T2 (mixed electrolytes) had increased serum osmolarity compared with the control (p<0.05) at 5 weeks of age. In conclusion, the high ambient temperature in this trial increased the mortality rate in the broilers and exacerbated FCR. The supplementation of both mixed electrolytes and ascorbic acid numerically reduced the mortality rate and slightly increased the weight gain. The electrolytes improved the serum osmolarity of the bird while the ascorbic acid supplement had the benefit of increasing serum GPx enzyme and decreasing serum MDA.