ABSTRACT. The prevalence of footpad dermatitis (FPD) in broiler chickens in Japan was investigated. In the first examination at slaughterhouses, lesions were commonly observed on the footpads of a total of 8,985 broiler chickens from 45 flocks on 36 farms. In 3 flocks, all the birds examined had lesions. In the other 42 flocks, the incidence of FPD ranged from 31.9% (81/254) to 99.5% (1/222). The footpad lesions were classified into 4 categories according to the severity of dermatitis as follows; score 0, 1,181 birds (13.1%); score 1, 2,992 birds (33.3%); score 2, 3,000 birds (33.4%); and score 3, 1,812 birds (20.2%). The mean scores of the flocks varied widely from 0.31 to 2.69. Males had higher mean scores than females. No significant differences were found between the mean scores of birds reared in windowless houses and those in open-sided houses. On 4 farms, the investigation was carried out in different seasons, and 3 of them showed higher mean scores in winter than in summer. Next, observation of 2,255 birds from 15 flocks on 5 farms during a 4-week rearing period revealed that FPD was already produced at 7 days of age and worsened with age.KEY WORDS: animal welfare, broiler, footpad dermatitis, lesion score.J. Vet. Med. Sci. 73(3): 293-297, 2011 Footpad dermatitis (FPD) has been regarded as a type of contact dermatitis of the footpad in chickens because it occurs on the points of contact with the ground and has been found in floor broilers under wet litter conditions [14]. The chicken feet, including the footpads, are edible parts of the chicken that are in high demand, especially in Southeast Asia. Chicken feet are exported from Japan and other countries, but feet with severe FPD are unfit for human consumption. They are condemned, resulting in significant economic losses. On the other hand, FPD is considered to be an indicator of animal welfare, especially in Europe, because the disease likely affects the health of the birds and inflicts suffering [7,22,26].So far, the prevalence of FPD in broiler chickens in Japan has not been reported. In this report, the first report on FPD in broiler chickens in Japan, we have investigated the prevalence of FPD in broiler chickens at processing plants and on farms. farms were slaughtered at 3 processing plants in the Minami-Kyushu area, and the other birds, which were reared on 7 farms, were slaughtered at 2 processing plants in the Tohoku area. The ages of the slaughtered birds ranged from 41 to 60 days (mean age of 53.2 days). In regard to the breed of the birds, 487 were Cobb chickens, 425 were Ross and Cobb chickens (mixture) and 8,073 were Ross chickens. Thirty-two flocks (6,386 birds) were reared in open houses, and 13 flocks (2,599 birds) were in windowless houses. Birds reared on 4 farms in Minami-Kyushu were examined twice, in summer (September) and in winter (January).
MATERIALS AND METHODS
Examination at slaughterhouses:Examination on farms: During the rearing period, a total of 2,245 broiler chickens (Ross breed) from 15 flocks on 5 farms in the Minam...