title: Broiler chickens dead on arrival: associated risk factors and welfare indicators.
abstract: The pre-slaughter phase of the production process has potentially important animal welfare implications, including mortality (recorded as "Dead on Arrivals"; DOA: ). To reduce DOA%, specific risk factors need to be identified. DOA% can also be used as a first and quick screening of pre-slaughter broiler welfare under commercial conditions. The aim of the present study was to identify risk factors for DOA% in commercial broiler flocks and to find associations between DOA% and animal-based indicators of broiler welfare during the pre-slaughter phase. Eighty-one transported flocks to five slaughter plants were assessed. Farmers provided information on the flock and observers gathered data on pre-slaughter factors. DOA% was recorded by slaughter plant personnel. The association between risk factors and DOA% was tested using linear mixed models, with slaughter plant as the random effect. Mean (± SE) DOA% was 0.30 ± 0.05% and median was 0.19% (range 0.04 to 3.34%). Two risk factors for DOA% were identified, both related to flock health status during the production phase. Higher DOA% was found when farmers did not check chick quality upon arrival (P = 0.011), although one extreme DOA% caused this significant effect. In addition, on-farm mortality during production (including selective culling) was negatively associated with DOA% (P = 0.011), potentially due to the selective culling on farm. Further research is needed on the impact of on-farm health status on welfare during the pre-slaughter phase, as the current study provided some evidence that on-farm factors are linked to mortality during the pre-slaughter phase. No specific characteristics of the pre-slaughter phase could be identified as risk factor for increased mortality. DOA% was positively associated with five welfare indicators, including indicators of thermal stress, which indicates the potential to use DOA% as a quick, cost-efficient screening tool for those welfare aspects.
authors.affiliation: Animal Sciences Unit, Institute for Agricultural and Fisheries Research (ILVO), Scheldeweg 68, 9090 Melle, Belgium.|Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
authors.forename: Leonie
authors.initials: L
authors.lastname: Jacobs
authors.affiliation: Animal Sciences Unit, Institute for Agricultural and Fisheries Research (ILVO), Scheldeweg 68, 9090 Melle, Belgium.
authors.forename: Evelyne
authors.initials: E
authors.lastname: Delezie
authors.affiliation: Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
authors.forename: Luc
authors.initials: L
authors.lastname: Duchateau
authors.affiliation: Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
authors.forename: Klara
authors.initials: K
authors.lastname: Goethals
authors.affiliation: Animal Sciences Unit, Institute for Agricultural and Fisheries Research (ILVO), Scheldeweg 68, 9090 Melle, Belgium frank.tuyttens@ilvo.vlaanderen.be.|Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
authors.forename: Frank A M
authors.initials: FA
authors.lastname: Tuyttens
mesh_terms: D000003:Abattoirs; D000822:Animal Husbandry / Q000706:statistics & numerical data*; D000827:Animal Welfare; D000818:Animals; D001530:Belgium; D002645:Chickens / Q000502:physiology*; D016014:Linear Models; D009026:Mortality; D012307:Risk Factors; D014186:Transportation
keywords: DOA; broiler welfare; mortality; pre-slaughter phase; risk factor