The dynamics of Salmonella occurrence in commercial laying hen flocks throughout a laying period

• Published in: Avian Pathology
• Language: English
• Published: Taylor & Francis 2012
• Subjects: Life Sciences; Faroe Islands
• Online Access: http://hdl.handle.net/2262/63833; https://doi.org/10.1080/03079457.2010.544290

Abstract Contaminated eggs and egg products have been recognised since many years as an important source of Salmonella infections in humans in the European Union and in the United States. Longitudinal studies can help to increase our knowledge about the dynamics of the occurrence of Salmonella in the course of a laying period. The total of 41 laying hen flocks, 18 in Belgium, 6 in Denmark and 17 in Germany were followed during an entire laying period. Samples taken from the empty cleaned and disinfected poultry houses were all negative for Salmonella. After hens arrived on the farms five pooled faecal samples, one pooled dust sample and 40 cloacal swabs (Belgium and Germany) or 40 swabs from fresh droppings (Denmark) were taken four times from 18 flocks, three times from 21 flocks and two times from 2 flocks in the course of the laying period. Ten flocks (two Belgian and eight German flocks) were tested up to three times positive for Salmonella. Forty three out of 50 positive samples contained Salmonella Enteritidis phage type 4 (29 isolates) or phage type 8 (14 isolates). The probability of subsequent Salmonella positive findings increased significantly in Salmonella positive flocks (p < 0.05, odds ratio = 6.4). However, the probability of finding Salmonella did not depend on the time of sampling in the laying period or the season. [e-mail] (Schulz, Jochen) [e-mail] (Van Hoorebeke, Sebastiaan) [e-mail] (Hald, Birthe) [e-mail] (Hartung, Jorg) [e-mail] (Van Immerseel, Filip) [e-mail] (Radtke, Ines) [e-mail] (Kabell, Susanne) [e-mail] (Dewulf, Jeroen) University of Veterinary Medicine Hannover, Foundation, Germany, Institute for Animal Hygiene, Animal Welfare and Farm Animal Behaviour - Bunteweg 17p--> - 30559 - Hannover - GERMANY (Schulz, Jochen) Ghent University, Obstetrics, Reproduction and Herd Health - Salisburylaan 133--> - 9820 - Merelbeke - BELGIUM (Van Hoorebeke, Sebastiaan) Technical University of Denmark, National Veterinary Institute, Department of poultry, fish and fur animals - ?rhus - DENMARK (Hald, Birthe) University of Veterinary Medicine Hannover, Foundation, Germany, Institute for Animal Hygiene, Animal Welfare and Farm Animal Behaviour - Hannover - GERMANY (Hartung, Jorg) Ghent University, Pathology, Bacteriology and Avian Diseases - Salisburylaan 133--> - 9820 - Merelbeke - BELGIUM (Van Immerseel, Filip) University of Veterinary Medicine Hannover, Foundation, Germany, Institute for Animal Hygiene, Animal Welfare and Farm Animal Behaviour - Hannover - GERMANY (Radtke, Ines) Food and Veterinary Agency, Dept. for Fish- and Animal Health - Faroe Islands - DENMARK (Kabell, Susanne) Ghent University, Obstetrics, Reproduction and Herd Health - Salisburylaan 133--> - 9820 - Merelbeke - BELGIUM (Dewulf, Jeroen) BELGIUM DENMARK GERMANY