title: Risk factors for Listeria monocytogenes contamination in French laying hens and broiler flocks.
abstract: The objective of this study was to identify potential risk factors for Listeria monocytogenes contamination in French poultry production. Eighty-four flocks of layer hens kept in cages and 142 broiler flocks were included in this study. For each production type, a questionnaire was submitted to farmers and fecal samples were taken to assess the L. monocytogenes status of the flocks during a single visit to the farm. Two logistic regression models (specific to each production) were used to assess the association between management practices and the risk of L. monocytogenes contamination of the flock. The prevalence of L. monocytogenes-positive flocks was 30.9% (95% CI: 21.0; 40.9) and 31.7% (95% CI: 24.0; 39.4) for cage-layers and broiler flocks, respectively. For layer flocks, the risk of L. monocytogenes contamination was increased when pets were present on the production site. When droppings were evacuated by conveyor belt with deep pit storage, the risk of L. monocytogenes contamination decreased significantly. Feed meal was found to be associated with a higher risk of L. monocytogenes contamination than feed crumb. For broiler flocks, the risk of L. monocytogenes contamination was increased when farmers did not respect the principle of two areas (clean and dirty) at the poultry house entrance. A first disinfection by thermal fogging and the absence of pest control of the poultry house before the arrival of the next flock was found to increase the risk of contamination. When litter was not protected during storage and when farm staff also took care of other broiler chicken houses, the risk of L. monocytogenes contamination increased significantly. In the case of the watering system, nipples with cups were found to decrease the risk of contamination.
authors.affiliation: Unité Hygiène et Qualité des Produits Avicoles et Porcins, Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (Anses) - site de Ploufragan-Plouzané, BP 53, 22 440 Ploufragan, France.
authors.forename: Kristell
authors.initials: K
authors.lastname: Aury
authors.forename: Sophie
authors.initials: S
authors.lastname: Le Bouquin
authors.forename: Marie-Thérèse
authors.initials: MT
authors.lastname: Toquin
authors.forename: Adeline
authors.initials: A
authors.lastname: Huneau-Salaün
authors.forename: Yolène
authors.initials: Y
authors.lastname: Le Nôtre
authors.forename: Virginie
authors.initials: V
authors.lastname: Allain
authors.forename: Isabelle
authors.initials: I
authors.lastname: Petetin
authors.forename: Philippe
authors.initials: P
authors.lastname: Fravalo
authors.forename: Marianne
authors.initials: M
authors.lastname: Chemaly
mesh_terms: D000822:Animal Husbandry / Q000379:methods*; D000818:Animals; D002645:Chickens; D004197:Disease Reservoirs / Q000662:veterinary; D005260:Female; D005506:Food Contamination / Q000517:prevention & control; D005602:France / Q000453:epidemiology; D008089:Listeria monocytogenes; D008088:Listeriosis / Q000453:epidemiology / Q000662:veterinary*; D008297:Male; D011201:Poultry Diseases / Q000453:epidemiology* / Q000382:microbiology; D015995:Prevalence; D012307:Risk Factors