title: The effect of level of straw bale provision on the behaviour and leg health of commercial broiler chickens.
abstract: This study aimed to assess the effect of the number of straw bales (SBs) provided on the behaviour and leg health of commercial broiler chickens. Houses containing ~23 000 broiler chickens were assigned to one of two treatments: (1) access to 30 SBs per house, '30SB' or (2) access to 45 SB per house, '45SB'. This equated to bale densities of 1 bale/44 m2 and 1 bale/29 m2 of floor space within houses, respectively. Treatments were applied in one of two houses on a commercial farm, and were replicated over six production cycles. Both houses had windows and were also artificially lit. Behaviour was observed in weeks 3 to5 of the cycle. This involved observations of general behaviour and activity, gait scores (0: perfect to 5: unable to walk) and latency to lie (measured in seconds from when a bird had been encouraged to stand). Production performance and environmental parameters were also measured. SB density had no significant effect on activity levels (P>0.05) or walking ability (P>0.05). However, the average latency to lie was greater in 30SB birds compared with 45SB birds (P<0.05). The incidence of hock burn and podo dermatitis, average BW at slaughter and levels of mortality and culling were unaffected by SB density (P>0.05). The results from this study suggest that increasing SB levels from 1 bale/44 m2 to 1 bale/29 m2 floor space does not lead to significant improvements in the welfare of commercial broiler chickens in windowed houses.
authors.affiliation: Institute for Global Food Security,School of Biological Sciences,Queens University Belfast,Belfast BT9 7BL,UK.
authors.forename: C L
authors.initials: CL
authors.lastname: Bailie
authors.affiliation: Institute for Global Food Security,School of Biological Sciences,Queens University Belfast,Belfast BT9 7BL,UK.
authors.forename: N E
authors.initials: NE
authors.lastname: O'Connell
mesh_terms: D000822:Animal Husbandry / Q000379:methods*; D000827:Animal Welfare; D000818:Animals; D001522:Behavior, Animal; D002645:Chickens / Q000502:physiology*; D004779:Environment Design; D005121:Extremities / Q000502:physiology; D005260:Female; D008297:Male; D016138:Walking / Q000502:physiology*