The Effect of Phytogenic Additive on Behavior During Mild - Moderate Heat Stress in Broilers

Abstract

The aim of this study was to evaluate the effect of phytogenic additive with anti-inflammatory and antioxidant properties on thermoregulatory behavior (lifting of the wings, high respiratory rate defined as open beaks) and water and feed intake in mild-moderate heat stressed Cobb 500 broiler chickens. From 28th day of chickens' age experimental group was supplemented with 0.1 % phytogenic additive based on Scutellaria baicalensis L. extract in the diet. At the age 30 days temperature was increased to 27 oC and kept the same till the end of experiment at 34 days of age. Ethological observation was performed 31st, 32nd and 33th days of experiment. Monitoring was performed in three observation periods at the start, in the middle and at the end of 18h day length, always for three consecutive hours. Changes in chickens' behavior among days and observation periods, as well as the influence of phytogenic additive were evaluated. Manifestations of thermoregulatory behavior were significantly higher (p < 0.001) in the middle and at the end of photoperiod. Significantly the highest number of chickens fed diets (p < 0.001) at the end of day-light, water intake was the lowest in the middle of the day (p < 0.001). Significantly the oftenest lifting of the wings (p < 0.001), high respiratory rate (p < 0.001) and feed intake (p = 0.017) were found in 33 days of chickens' age. Feeding of phytogenic additive did not affect water intake and feed intake, anyway significantly reduced (p < 0.001) thermoregulatory behavior.