Risk and indicators of condemnation of male turkey broilers in western France, February-July 2006

Abstract

A field study was conducted to estimate the sanitary condemnation proportion in male turkey broiler flocks, to describe the reasons for condemnation and the related macroscopic lesions, and to investigate whether primary production information would predict the risk of condemnation. Male turkey standard broiler flocks (117) were randomly selected in the 13 slaughterhouses located in Western France, from February to July 2006. The flocks were monitored from their arrival at the slaughterhouse until the results of the post mortem sanitary inspection. Information about rearing conditions, health history, catching and loading conditions, transportation to the slaughterhouse and slaughtering was also collected. Sampling design was considered in the calculations and the condemnation proportion was modelled using a negative binomial regression, accounting for clustering within slaughterhouse. The within-flock weighted average condemnation proportion was 1.8% (95% confidence interval, 1.3-2.3%). Emaciation, arthritis-polyarthritis and congestion were the main reported official reasons for condemnation, representing 76% of the condemned carcases. Three variables were significantly associated with increased risk of condemnation: observed locomotor disorders on the farm, high cumulative mortality 2 weeks before slaughter, and clinical signs observed by the Veterinary Services during the ante mortem inspection at the slaughterhouse. The final model explained 35% of the total variation in condemnation risk. Half of this explained variation could be attributed to locomotor disorders observed during rearing. The sensitivity and specificity of the model to predict a high flock condemnation risk were 80% and 74%, respectively, when using an optimum threshold of 0.95% to define high risk. The results of this study suggested that the variables found to be associated with condemnation proportion were markers of increased risk and could be used as indicators. These risk indicators can easily be retrieved from the pre-existing regulatory document transmitted before flock arrival at the slaughterhouse and could be used to screen flocks before slaughter, according to their expected risk of condemnation.