Response of Heat-Stressed Commercial Broilers To Dietary Supplementation of Organic Chromium

Abstract

The responses of broilers to organic chromium (Cr) fed under heat stress were investigated. About 256 day old Cobb 500 broilers were divided into four dietary groups and fed iso-caloric and iso-nitrogenous diets containing 0, 0.005, 0.010 and 0.015% organic Cr (yeast fermented) up to 35 days. Feed intake, body weight gain and feed conversion ratio (FCR) were measured. Blood samples were collected at 22 and 34 days of age to determine serum parameters. On 35 days, 2 broilers from each replicate were slaughtered to determine carcass traits. Body weight and weight gain of broilers fed Cr were significantly increased at 21 and 35 days (P<0.01). Feed intake was not affected up to 21 days but increased in Cr groups (P<0.05) from 22 to 35 days. The lowest FCR was recorded for 0.010% Cr (P<0.01). A significant decrease (P<0.01) in abdominal fat were observed in Cr group. Antibody titer against Newcastle virus was increased (P<0.01) in both 0.005 and 0.010% Cr at 22 days. Heterophyl to lymphocyte ratio was decreased (P<0.01) in 0.010 and 0.015% Cr. It was therefore concluded that 0.010% dietary organic Cr supplementation may be used to improve productive performance and immune status with a reduction in abdominal fat content of broilers under heat stress condition.