IMPACT OF STOCKING DENSITY, BREED, AND FEATHERING ON THE PREVALENCE OF ABDOMINAL SKIN SCRATCHES IN BROILER-CHICKENS

Associations between abdominal skin scratches and stocking density, st rain of birds, and degree of feathering were investigated in a clinica l trial. Four hundred eighty 1-day-old male broiler chicks from two di fferent strains (A and B) were assigned to four groups: 1) high densit y (0.07 m(2)/bird) and strain A, 2) high density and strain B, 3) norm al density (0.14 m(2)/bird) and strain A, and 4) normal density and st rain B. Birds were examined for scratches and feathering at 28, 35, an d 42 days of age. Two outcomes were considered for scratches: presence (yes/no) and severity (severe [if a deep cut or at least three superf icial cues were present]/not severe). Only the examination at 35 days of age was blind. The outcome ''scratches'' was significantly associat e. with stocking density at all ages (P less than or equal to 0.0001), strain A at 28 days of age (P = 0.0480), and poor feathering at 35 da ys of age (P less than or equal to 0.0001). The out come ''severe scra tches'' was significantly associated with stocking density at 35 (P = 0.0003) and 42 days of age (P = 0.0021), strain A at 35 (P = 0.0089) a nd 42 days of age (P = 0.0306), and poor feathering ac 35 days of age (P = 0.0018). Stocking density, strain of birds, and degree of feather ing could be considered as potential risk factors for abdominal scratc hes in broiler chickens.