Many factors contribute to the stress of transporting broilers from the farm to the processing plant. Using a motion simulation machine, a total of 144 male broilers were employed to determine the effect of motion, vibration, and feed withdrawal during transportation on serum biochemical parameters, postmortem muscle metabolism, and meat quality of broilers. The results indicated that transportation did not affect the activity of lactate dehydrogenase, γ-glutamyl transferase, aspartate aminotransferase, creatine kinase, and glucose in the serum, glutathione peroxidase in the breast and thigh muscle, nitric oxide synthase (NOS) in the breast, and heat stress protein 70 mRNA expression level in the liver (p > 0.05). Serum triiodothyronine, thyroxine, and insulin concentration declined with 2 h transportation (p < 0.05) and recovered with 4 h transportation (p < 0.05). NOS concentration in the thigh increased with 2 h transportation (p < 0.05) and recovered with 4 h transportation (p < 0.05). Two-hour and 4 h transportation increased the activity of superoxide dismutase in both muscles. Malondialdehyde, lactic acid, and drip loss24 h in both thigh and breast muscles increased, and glycogen in both muscles decreased with increasing transportation times (p < 0.05). Two-hour transportation did not influence pH45 min and pH24 h in the breast and thigh muscle, but these indexes decreased with 4 h transportation. This experiment supports and extends previous work that identified transportation as a major risk in relation to bird welfare and meat quality.
Effects of constant and cyclic heat stress on muscle metabolism and meat quality of broiler breast fillet and thigh meat
