The Effect of Different Photoperiod and Stocking Density on Colour, pH and TBARS Values in Broilers Meat

Present research was conducted to determine the effects of various lighting programmes and stocking density on colour, pH and TBARS parameters of meat in broilers. A total of 320 male chicks (Ross 308), one day old, were used in the study. Chicks were kept in different rooms where two lighting programs [Constant Lighting (CL): 16 h light, 8 h dark; Intermittent Lighting (IL): 4 h light, 2 h dark] were applied. Experimental design was consisted of two lighting programs and each lighting group had two stocking density subgroups [Normal density (ND): 12 broilers/m^2; High density (HD): 20 broilers/ m2], five replicates each. The experiment lasted for 42 d. Effect of stocking density on breast meat pH was found to be significant (P 0.05). Colour parameters such as L*, a* and b* determined in breast meat were not affected either by lighting programme or stocking density. Lighting programmes significantly (P 0.05) effected the a* colour criteria, determined in thigh meat. TBARS values were affected by stocking density (P 0.05). In conclusion, the stocking density had a significant effect on pH and TBARS and the lighting programme affected the a* value in thigh meat, while the interaction between lighting programme x stocking density had also a significant effect on the L* and b* values of breast meat.