Impacts of dietary energy level and terracotta drinker on the performance of heat-stressed broiler chickens

The present study was conducted with the objective of evaluating the effects of a terracotta drinker and dietary energy level on the physiological response and growth performance of broiler chickens reared in a hot environment. A total of 200-day-old Cobb 500 broiler chicks (39.6 ± 3.4 g) were divided into four distinct treatment groups in a 2 x 2 factorial arrangement of drinker type (plastic or terracotta) and diet energy density (3300-3300-3250 kcal/kg or 3300-3250-3100 kcal/kg for starter-grower-finisher, respectively). Each group consisted of five replicate pens. The water intake, feed intake and feed conversion ratio exhibited a significant decrease (p < 0.01) in the terracotta group as compared to the plastic group. A significant increase in body weight was observed in the terracotta drinker group in comparison to the plastic drinker group (p < 0.01). However, this increase was more pronounced in individuals with lower energy levels. The mortality rate, the rectal temperature and the respiration rate of broilers receiving water from the terracotta drinker and fed on a low-energy diet were significantly lower (p < 0.01). In the case of broilers that received water from the terracotta drinker, higher values were observed for both villus length and the villus height/crypt depth ratio (p < 0.05). It can be concluded that the terracotta drinker can be more efficient in reducing the behavioral response to heat stress and can improve liveability and growth performance. However, the optimal outcomes were observed in conjunction with a low diet energy density.