title: Effect of Organic Acids on Salmonella Shedding and Colonization in Pigs on a Farm with High Salmonella Prevalence.
abstract: This study builds on the results of a previous study in which six commercial feed products based on organic acids were evaluated with respect to Salmonella contamination of piglets in an artificially challenged seeder model. In the present study, the efficacy of three of these commercial products was assessed for Salmonella reduction in fattening pigs on one closed farm with a natural high Salmonella prevalence. In each of four fattening compartments, one of the following feed treatments was evaluated during two consecutive fattening rounds: (i) butyric acid (active ingredients at 1.3 kg/ton of feed; supplement A1), (ii) a combination of short-chain organic acids (mixture of free acids and salts) and natural extracts (2.92 kg/ton; supplement A4), (iii) a 1:1 blend of two commercial products consisting of medium-chain fatty acids, lactic acid, and oregano oil (3.71 kg/ton; supplement A5+A6), and (iv) a control feed. On the farm, the Salmonella status of the fattening pigs was evaluated by taking fecal samples twice during the fattening period. At the slaughterhouse, samples were collected from the cecal contents and the ileocecal lymph nodes. Salmonella isolates were serotyped and characterized by pulsed-field gel electrophoresis. This farm had a particularly high number of pigs shedding Salmonella with a wide variety of sero- and pulsotypes. Only the feed blend based on the medium-chain fatty acids was able to significantly reduce Salmonella prevalence both on the farm and at the slaughterhouse. With this combined supplement, the Salmonella reduction in the feces at slaughter age, in cecal contents at slaughter, and the lymph nodes was 50, 36, and 67%, respectively, compared with the control animals. This promising finding calls for further investigation including cost-efficiency of this combined feed product and its effect on the animals.
authors.affiliation: Technology and Food Science Unit, Institute for Agricultural and Fisheries Research, Brusselsesteenweg 370, 9090 Melle, Belgium. geertrui.rasschaert@ilvo.vlaanderen.be.
authors.forename: G
authors.initials: G
authors.lastname: Rasschaert
authors.affiliation: Department of Applied Biosciences, Faculty of Bioscience Engineering, Ghent University, Valentin Vaerwyckweg 1, 9000 Gent, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Michiels
authors.affiliation: Laboratory for Animal Nutrition and Animal Product Quality, Department of Animal Production, Faculty of Bioscience Engineering, Ghent University, Proefhoevestraat 10, 9090 Melle, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Tagliabue
authors.affiliation: Laboratory for Animal Nutrition and Animal Product Quality, Department of Animal Production, Faculty of Bioscience Engineering, Ghent University, Proefhoevestraat 10, 9090 Melle, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Missotten
authors.affiliation: Laboratory for Animal Nutrition and Animal Product Quality, Department of Animal Production, Faculty of Bioscience Engineering, Ghent University, Proefhoevestraat 10, 9090 Melle, Belgium.
authors.forename: S
authors.initials: S
authors.lastname: De Smet
authors.affiliation: Technology and Food Science Unit, Institute for Agricultural and Fisheries Research, Brusselsesteenweg 370, 9090 Melle, Belgium; Department of Pathology, Bacteriology, and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Heyndrickx
mesh_terms: D000003:Abattoirs; D000818:Animals; D002432:Cecum / Q000382:microbiology; D019587:Dietary Supplements / Q000032:analysis; D016521:Electrophoresis, Gel, Pulsed-Field; D005227:Fatty Acids / Q000378:metabolism*; D005243:Feces / Q000382:microbiology; D015995:Prevalence; D012475:Salmonella / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D012481:Salmonella Infections, Animal / Q000453:epidemiology / Q000378:metabolism / Q000382:microbiology*; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology / Q000378:metabolism / Q000382:microbiology*
chemical_list: D005227:Fatty Acids