Improving the breast meat quality and carcass characteristics of heat-stressed broilers by feeding chromium supplementation.

In this experiment 240 one-day-old male broilers (Ross 308) in heat stress condition (33±3°C) were allocated to four treatments in a completely randomized design. Treatments were supplemented with 0 (control), 500, 1000 or 1500 ppb chromium (Cr) in the form of Cr nicotinate. Twelve chicks from each treatment were slaughtered at 42 d, carcass and abdominal fat pad were removed, and weighed. Breast meat was skinless, deboned and some muscles from the breast were immediately stored at −20 °C for assessing intramuscular fat and crude protein content, and others were stored individually in plastic bags at 4 °C in refrigerator for 2 and 6 days to measure malonaldehyde and tyrosine value as the indicator of lipid peroxidation (oxidative stability) and proteolysis, respectively. At 12 h after slaughter the breast muscle pH was determined. Chromium supplementation increased carcass yield and protein content of meat (P<0.01). Moisture, intramuscular fat content pH and meat proteolysis were not affected by supplemental Cr. Storage time increased lipid peroxidation and proteolysis of breast meat (P<0.01). Supplemental Cr decreased abdominal fat content and lipid oxidation of breast muscle for 2 days of storage (P<0.05).