Effect of brooders on feather pecking and cannibalism in domestic fowl (Gallus gallus domesticus)

Several studies have shown that the tendency to feather peck is influenced by events early in life and preventive measures should therefore be introduced at hatching. Separating inactive chicks from active chicks by providing dark electrical brooders was predicted to reduce the risk of chicks developing pecking preferences for conspecifics. Twelve groups of 15 layer hen chicks (Lohmann Tradition) were reared in pens (2.55 m(2)); during the first 5 weeks after hatching six pens were provided with dark brooders and six pens with heating lamps. All pens were observed continuously for 30 min per pen once a week until the chickens were 23 weeks old, and each bout of severe feather pecks was recorded. The chickens were observed several times daily, and all injured individuals were removed from the experiment. Faecal samples were collected from the pens when the chicks were 16, 17 and 18 days old and analysed for corticosterone metabolites. At the end of the experiment, the plumage and skin damage were scored. Data were analysed using repeated measures ANOVA. The dark brooders completely prevented severe feather pecking in the dark brooder pens, whereas the frequency of severe feather pecking rose with age in the heating lamp pens (treatment x age: P < 0.0001). At the last observation (week 23), the frequency of severe feather pecking bouts in the dark brooder pens was 0.3 +/- 0.4 (mean S.E.) compared to 31.3 +/- 10.1 in the heating lamp pens. The frequency of gentle feather pecking was significantly higher in the heating lamp pens at all ages (P < 0.0001). Mortality followed the same pattern as severe feather pecking; it was almost nonexistent in the dark brooder pens, whereas from point of lay it continued to rise with age in the heating lamp pens (1 versus 24 casualties, treatment x age: P < 0.0001). The high level of severe feather pecking in the heating lamp pens was also reflected in the scores of plumage and skin damage as both were found to be significantly higher in the heating lamp pens (plumage: P = 0.0004; skin: P = 0.0273). There was no difference between treatments in concentrations of faecal corticosterone metabolites (P = 0.8146). The results suggest that the provision of dark brooders has a long-lasting reducing effect on the frequency of feather pecking and cannibalistic attacks, resulting in reduced mortality and an improved condition of both plumage and skin. (c) 2005 Elsevier B.V. All rights reserved.