Effect of seasonal temperatures and ascorbic acid supplementation on performance of broiler chickens maintained in closed and open-sided houses

The efficacy of ascorbic acid in drinking water on performance of broiler chickens under closed and open-sided houses during hot (ambient temperature 36°C) and cool (ambient temperature 23°C) seasons were studied. The temperatures inside the poultry houses were 26°C (closed), 29°C (open-sided), 32°C (closed) and 37°C (open-sided) for cool and hot seasons, respectively. One-day-old chicks (432 birds) were housed in each closed and open-sided environment for each season. Birds were maintained under 23 hrs light and 1 hr dark cycle and offered ad libitum access water and feed. Broilers in both houses were randomly subjected to four drinking water treatments (9 birds in each 6 replicates/treatment): 0, 100, 200 and 300 ppm ascorbic acid. Feed intake, body weight gain, feed conversion ratio and rectal temperatures were recorded weekly. Ascorbic acid supplementation at 200-300 ppm was associated with a reduction in rectal temperatures during the hot season. Open-sided house depressed body weight gain and feed conversion ratio (P < 0.05) during hot season. Compared to the control group, ascorbic acid improved feed intake, body weight gain and feed conversion ratio by 6%, 9% and 3% (cool season) and 8%, 11% and 5% (hot season). Birds supplemented with 200 ppm ascorbic acid had (P < 0.05) higher feed intake, body weight gain and feed conversion ratio than the control group during the cool season, while 300 ppm (P < 0.05) improved broiler performance including feed intake, body weight gain and feed conversion ratio during the hot season. Bird's rectal temperature was higher (P < 0.05) during hot season in open-sided house and (P < 0.05) reduced by supplementing 200-300 ppm ascorbic acid. This study demonstrated that seasonal temperatures had a significant effect on broiler performance in open-sided house. Supplementation of drinking water with 200-300 ppm ascorbic acid ameliorated broiler performance in open-sided housing at high ambient temperatures.