Mating-Related Traumatic Lesions in Slow-Growing Broiler Breeder Hens: Morphological and Physiological Correlates

In broiler breeder flocks, mating may cause traumatic skin lesions in hens, yet their biological significance remains insufficiently understood. This study aimed to investigate associations between mating-related lesions and physical and physiological status in broiler breeder hens, focusing on lesion severity and anatomical location. At 40 weeks, 39 hens were examined, including 29 with mating-related lesions and 10 lesion-free controls. Birds underwent clinical examination, body weight and plumage assessment, serum corticosterone measurement, and ultrasonographic evaluation of ovarian activity. Affected hens had lower body weight than controls, and 58.6% showed ovarian inactivity. Within affected hens, body weight was positively associated with plumage score and ovarian activity. Gross lesion severity was not consistently associated with body weight, plumage condition, or ovarian activity, whereas lesion location provided additional information on these indicators. Hens with cephalic lesions had lower body weight, poorer plumage condition, and lower ovarian activity than hens with trunk lesions, despite less severe lesions macroscopically. Serum corticosterone concentrations did not differ between groups or vary with lesion severity or location. These findings suggest that mating-related lesions may reflect more than superficial injury and that lesion location, particularly cephalic involvement, may provide useful information on the biological status of affected hens.