Beak and oral lesions in broiler breeding fowl.

Beak, tongue and other oral lesions were observed in broiler breeding fowl reared under a regime of separate sex feeding. Seventy four per cent of the male birds examined at necropsy, at 60 weeks of age, had beak lesions. Severe beak lesions, in both male and female birds, resulted in pronounced beak deformities which made feeding difficult or impossible. Beak lesions occurred at a number of sites on maxillae and mandibles but the pathogenesis of all lesions, including those of the tongue and oral cavity, appeared to be similar. It is postulated that the primary event was either direct or indirect injury of the epidermis, followed by bacterial infection and tissue necrosis. Dermatitis may arise in a number of ways and certain husbandry systems may encourage beak trauma. Because pronounced beak deformities and concurrent osteomyelitis were the usual outcome of progressive lesions, special vigilance is required to identify and cull affected birds whose welfare is seen to be at risk.