This study examined the relationships among three traits often used in welfare assessment in five breeds of laying hens (all Spanish breeds). The birds were housed in group pens containing 75 hens and 15 roosters. Plumage was assessed at 72 wk of age, and 120 birds were selected that represented poor (60) and perfect (60) feather condition. These birds were then tested for their tonic immobility response, in which a higher value represents increased fearfulness. They were also blood sampled and the ratio of heterophils to lymphocyte ratio determined. This ratio is indicative of stress and increased in stressed birds. There were breed differences in all traits, but the relationships among the traits were similar in all breeds. Hens with poor feather condition showed shorter tonic immobility (less fearful), but higher heterophil/lymphocyte ratios (more stressed) than did well feathered animals.









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