title: Associations among gait score, production data, abattoir registrations, and postmortem tibia measurements in broiler chickens.
abstract: Lameness and impaired walking ability in rapidly growing meat-type broiler chickens are major welfare issues that cause economic losses. This study analyzed the prevalence of impaired walking and its associations with production data, abattoir registrations, and postmortem tibia measurements in Norwegian broiler chickens. Gait score (GS) was used to assess walking ability in 59 different commercial broiler flocks (Ross 308) close to the slaughter d, 5,900 broilers in total, in 3 different geographical regions. In each flock, 100 arbitrary broilers were gait scored and 10 random broilers were culled to harvest tibias. Abattoir registrations on flock level were collected after slaughter. A total of 24.6% of the broilers had moderate to severe gait impairment. The broilers were sampled in 2 stages, first slaughterhouse/region, and then owner/flock. The final models showed that impaired gait is associated with first-week mortality (P < 0.05), region (P < 0.001), height of tibias mid-shaft (P < 0.05), and calcium content in the tibia ash (P < 0.05), and negatively associated with DOA (P < 0.05). The prevalence of impaired gait indicates that this is a common problem in the broiler industry in Norway, although the mean slaughter age is only 31 d and the maximum allowed animal density is relatively low. Impaired walking ability could not be predicted by the welfare indicators footpad lesion score, total on-farm mortality, and decreasing DOA prevalence. Further studies are needed to explore the relationship between first-week mortality and gait score.
authors.affiliation: Animalia, Norwegian Meat and Poultry Research Centre, NO-0513 Oslo, Norway.
authors.forename: K E
authors.initials: KE
authors.lastname: Kittelsen
authors.affiliation: Norwegian Veterinary Institute, Veterinary Public Health Section, NO-0454 Oslo, Norway.
authors.forename: B
authors.initials: B
authors.lastname: David
authors.affiliation: Norwegian University of Life Sciences, Faculty of Veterinary Medicine and Biosciences, NO-0033 Oslo, Norway.
authors.forename: R O
authors.initials: RO
authors.lastname: Moe
authors.affiliation: Department of Animal Sciences, University of Aarhus, Blichers Allé 20, DK-8830 Tjele, Denmark.
authors.forename: H D
authors.initials: HD
authors.lastname: Poulsen
authors.affiliation: Department of Food Science, University of Aarhus, Blichers Allé 20, DK-8830 Tjele, Denmark.
authors.forename: J F
authors.initials: JF
authors.lastname: Young
authors.affiliation: Norwegian University of Life Sciences, Faculty of Veterinary Medicine and Biosciences, NO-0033 Oslo, Norway.
authors.forename: E G
authors.initials: EG
authors.lastname: Granquist
mesh_terms: D000003:Abattoirs / Q000706:statistics & numerical data*; D000822:Animal Husbandry / Q000706:statistics & numerical data; D000827:Animal Welfare / Q000706:statistics & numerical data; D000818:Animals; D015519:Bone Density; D002118:Calcium / Q000032:analysis; D002645:Chickens; D003430:Cross-Sectional Studies; D005684:Gait; D009026:Mortality; D009664:Norway / Q000453:epidemiology; D011201:Poultry Diseases / Q000453:epidemiology*; D013977:Tibia / Q000033:anatomy & histology* / Q000737:chemistry; D016138:Walking
chemical_list: D002118:Calcium
keywords: animal welfare; broiler; gait score; lameness; welfare indicator