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The effects of gamma irradiation on microbiological and chemical qualities of four kinds of poultry feeds were investigated. The viable counts of total bacteria in the samples were 10^5 to 10^6/g. They were reduced by 2 to 3 log cycles after 3 to 5 kGy irradiation, and were completely eliminated with irradiation of 7 kGy. Coliforms and enteric pathogens were contaminated in high levels in all samples, ranging from 1.2 ×10⁴ to 1.7 ×10^5/g and 4.0 ×10 to 2.6 ×10³/g, respectively, They were sterilized by 3 to 5 kGy irradiation. Fungi, ranging from 10² to 10⁴/g, mainly osmophiles were identified as Aspergillus and Penicillium. ´they were eliminated to a undetectable level by 5 to 10 kGy irradiation. Six kinds of species, including Aspergillus flavus, were potential mycotoxin producers. Chemical components, such as proximate compositions, and mineral contents were not affected by the gamma irradiation. However, TBA values and amino acid content seemed to be affected by gamma irradiation.
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