Feeding from perches in an aviary system reduces aggression and mortality in laying hens

Some commercial aviary systems for laying hens allow birds to access feed by standing on perches instead of platforms. Despite reports that providing laying hens with perches relates to reduced aggression and cannibalism, and increased prevalence of keel bone damage, the impact of feeding from perches on behaviour, health, and production has not been investigated. The current work studied the effects of feeding either from perches (Perch Treatment) or platforms (Platform Treatment) on behaviour, health, and production. The experiment was conducted in a quasi-commercial bam divided into 20 identical pens with 196 hens per pen to compare treatment (Perch vs. Platform) and hybrid (Nick Chick vs. Brown Nick) in a 2 x 2 factorial design. We analysed behaviour (from video recordings taken at 30, 37, and 51 weeks of age), health (at 29 and 65 weeks of age), feather condition (at 21, 44, and 65 weeks of age) and productivity parameters (collected daily from 18 to 65 weeks of age). Hens of the Perch Treatment showed less aggression at the feeder (z-value = - 1.942, p = 0.05), less jostling followed by feeding (at 30 weeks of age: z-value = - 4.191, p < 0.001; and 37 weeks of age: z-value = - 3.059, p = 0.022; but not at 51 weeks of age: p = 0.823) and followed by a behaviour other than feeding (z-value = - 7.075, p < 0.001), as well as more body instability (balance movements and falls combined) behaviours (Brown Nick: z-value = 4.338, p < 0.001, Nick Chick: z-value = 7.550, p < 0.001) than hens from the Platform Treatment. There was no difference in keel bone fractures between the treatments (p = 0.555). In the Perch Treatment, we recorded a tendency for lower overall mortality (t-value = - 1.807, d.f.= 17, p = 0.089) and the Brown Nick hybrid had lower mortality resulting from cannibalism (t-value = - 2.955, d.f. = 8, p = 0.021), laid more eggs (z-value = - 2.853, p = 0.022), and had a greater feed conversion ratio (z-value = 3.947, p < 0.001) than in the Platform Treatment. Due to reduced aggression and jostling, as well as a tendency for lower overall mortality, we conclude that the Perch Treatment is a superior alternative with improved welfare to the Platform.