title: Assessment of the anti-Salmonella activity of commercial formulations of organic acid products.
abstract: Organic acid products are widely used in the UK poultry industry as feed or water additives. Claims for Salmonella control are made for some of these products, but there are few studies comparing the anti-Salmonella effect of the various products in tests that reflect field application. The present studies examined the effects of 13 commercial blends (four water products and nine feed products) on Salmonella Enteritidis and Typhimurium strains. Initial screening, in nutrient broth, of all products with all strains revealed little variation between strains in respect of maximum inhibitory and bactericidal dilutions of each product. However, between the products there was wide and significant variation in the maximum inhibitory and bactericidal dilutions, spanning a 700-fold range in the case of bactericidal dilutions for feed-associated products. Further tests were performed, examining reductions in inoculated Salmonella numbers in various matrices (water, feed, soiled litter, crop and caecal contents) following the addition of the products at recommended inclusion rates. One product, incorporating formaldehyde in addition to organic acid, was consistently most active in all matrices, exceeding reductions associated with other products by 1 to 3 log units at most time points. Many products showed only modest anti-Salmonella activity, amounting to 0 or 1 log unit above negative controls at many time points, and the most active products were not the same in all matrices. Tap water appeared to enhance the ability of products to reduce Salmonella, in comparison with bottled mineral or river water.
authors.affiliation: Department of Bacteriology and Food Safety, Animal Health and Veterinary Laboratories Agency, Addlestone, Surrey, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Wales
authors.forename: Ian
authors.initials: I
authors.lastname: McLaren
authors.forename: André
authors.initials: A
authors.lastname: Rabie
authors.forename: Rebecca J
authors.initials: RJ
authors.lastname: Gosling
authors.forename: Francesca
authors.initials: F
authors.lastname: Martelli
authors.forename: Robin
authors.initials: R
authors.lastname: Sayers
authors.forename: Robert
authors.initials: R
authors.lastname: Davies
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002264:Carboxylic Acids / Q000494:pharmacology*; D005557:Formaldehyde / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D011200:Poultry; D011201:Poultry Diseases / Q000382:microbiology* / Q000517:prevention & control*; D012481:Salmonella Infections, Animal / Q000517:prevention & control*; D012477:Salmonella enteritidis / Q000187:drug effects*; D012486:Salmonella typhimurium / Q000187:drug effects*; D013045:Species Specificity; D014867:Water / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D002264:Carboxylic Acids; D014867:Water; D005557:Formaldehyde