The Effect of Perch Cooling and Perch Height on Some Bone Strength Parameters in Broilers Reared in Summer

Abstract

This study was carried out to investigate the effects of perch cooling and two different perch heights on physical (the weight, length, diameter, strength index, and weight-length index) and strength (strength, stiffness, elastic modulus, ultimate force) properties of tibiotarsus of broilers reared in summer conditions. A total of 450 one-d-old Ross-308 broiler chicks were used as the material. Chicks were allocated into 10 pens which has 15 chicks in each as to a 3x2x2 experimental design with three replication. Perch temperature was set to 10 o C for cooled perches while perches were attached 7.5 and 15 cm off the floor. The position of both cooled and non-cooled perches were set to make animals pass over the perch for feeding and drinking. Results revealed that tibia weights in both 7.5 (19.39 g) and 15 cm (19.01 g) perch height groups were higher than the no-perch (17.24 g) group (P<0.001). Bones from the cooled perch group were found heavier (19.58 g-109.48 mm) and longer than the no-cooled (18.29 g-105.55 mm) group (P<0.001). As to ultimate force (Fmax), the greatest force (264.2 N) was required for bones in a group with 7.5 cm perch height (P<0.05). There were also similar significant differences in perch cooling and sex parameters while both perch application and perch cooling do not affect bone strength and elastic modulus.