The impact of traumatic limb injuries resulting from operations related to transport for slaughter on biochemical indices in end-of-lay hens

Abstract

The study focused on the welfare of end-of-lay hens during their transportation for slaughter from the viewpoint of the stress load on hens resulting from unsatisfactory treatment that leads to traumatic injury to the limbs of hens detected during the veterinary examination of hens at the slaughterhouse. Blood samples were taken during bleeding after slaughter at the slaughterhouse for the determination of corticosterone and other biochemical indices from 35 hens with traumatic limb injuries and 35 hens without traumatic limb injuries. The stress load during the transportation of hens for slaughter potentiated by traumatic injuries was found to increase (P < 0.01) the plasma corticosterone concentration as an indicator of stress in birds (6381 pg/ml vs. 3681 pg/ml) and affect the plasma concentration of some biochemical indices, in particular increasing (P < 0.05) the level of total protein and albumin and decreasing (P < 0.05) levels of triglycerides, calcium and alanine aminotransferase. These findings demonstrate that hens with traumatic limb injuries occurring during the course of transport (loading, transport, unloading) are burdened by a greater degree of stress than hens that have not suffered traumatic injuries. From the viewpoint of the protection and welfare of end-of-lay hens, this study unequivocally demonstrates the necessity of the corresponding careful handling of birds during their loading onto and unloading from means of transport during transportation to the slaughterhouse – the kind of handling that does not cause injuries and, thereby, an increased stress load on hens slaughtered at the slaughterhouse.