Antibacterial activity of formic and propionic acids in the diet of hens on Salmonellas in the crop

Br Poult Sci. 1997 Mar;38(1):59-65. doi: 10.1080/00071669708417941.


1. The inclusion of formic and propionic acids in the form of Bio-Add to the food of hens made no difference to the pH of the intestinal tract, but resulted in higher concentrations of these acids in the contents of the crop and gizzard. 2. Organic acids in the crop contents were bactericidal for Salmonella serotype Enteritidis PT4 in vitro, and also caused sub-lethal damage because fewer cells were recovered on selective salmonella media (brilliant green phenol red agar) than on non-selective media (nutrient agar). 3. Inclusion of Bio-Add in the food at 12g/kg may reduce the number of lactic acid-producing bacteria in the crop, and hence the amount of naturally produced organic acids.

MeSH terms

  • Animal Feed*
  • Animals
  • Anti-Bacterial Agents*
  • Chickens
  • Female
  • Formates / administration & dosage
  • Formates / pharmacology
  • Formates / therapeutic use*
  • Gastrointestinal Contents / chemistry*
  • Hydrogen-Ion Concentration
  • Microbial Sensitivity Tests
  • Poultry Diseases*
  • Propionates / administration & dosage
  • Propionates / pharmacology
  • Propionates / therapeutic use*
  • Salmonella Infections, Animal / prevention & control*
  • Salmonella enteritidis / drug effects


  • Anti-Bacterial Agents
  • Formates
  • Propionates
  • formic acid
  • propionic acid