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Don’t rely on disinfectant
Disinfectant use is essential but not a panacea for all ills or a magic cure on its own. Cleanness of surfaces to be disinfected and application methods employed rather than the actual chemical disinfectant used will usually determine whether a disease free house is achieved.
Dirt and organic matter such as dried and hardened faeces, mucous, feathers and spilt feed will inhibit disinfectant action because there must be direct contact between the biocide and the pathogen.
Modern disinfectants are put through stringent laboratory tests such as the Kelsey Sykes Test that simulates real working conditions in the poultry house. They assess biocidal activity in the face of repeated ‘challenge’ by organic matter and effect of hard water caused by high levels of calcium or magnesium salts.
Many chemicals including strong acids and bases, chlorine generators, phenols, aldehydes, quaternary ammonium compounds, iodophors and peroxygen compounds possess disinfectant action. Some such as iodine based compounds have a long history of use but limited action and a relatively narrow range of kill. Others like formaldehyde though widely used in the past are now largely avoided for reasons of safety to both birds and poultry workers.
Modern disinfectants are potent biocides with broad-spectrum activity and a long contact time to kill pathogenic microbes. For instance, peroxygen compounds that disrupt and destroy microbes through oxidation reactions will destroy most types of pathogenic microbe. These include bacteria (e.g. Salmonella typhimurium and Escherichia coli) viruses (e.g. avian influenza and infectious bronchitis) and fungi (e.g. Aspergillus fumigatus and Canida albicans). Contact time is increased by the addition of a surfactant. Surfactants are surface-active chemicals that lower the surface tension of the diluted disinfectant mixture to increase penetration and spreading power of water-based biocides.
