SummaryThe effect of gamma-irradiation and the antimicrobial food additives on growth and aflatoxin B, production by A . fluuus NRRL 5520 in poultry diet was investigated. By increasing the irradiation doses the viable population as well as aflatoxin B, production decreased greatly. No growth and no detection of aflatoxin production occurred in poultry diet after treatment with 6 kGy. The addition of the antimicrobial food additives resulted in a significant decrease in aflatoxin B,. Growth and toxin production was completely inhibited by 0.64% sodium propionate, 0.134% potassium sorbate and 0.1 % sodium bisulfite. The combination treatments between gamma-irradiation (3 kGy) and sodium propionate (0.48%), potassium sorbate (0.022% and 0.044%) and sodium bisulfite (0.0334% and 0.0667%) inhibited, completely the fungal growth and aflatoxin B, production. At 5 kGy, no growth was recorded and aflatoxin B, production was completely inhibited at all tested levels of priopionate, sorbate and bisulfite. The combined effects between gamma-irradiation and the antimicrobial agents had a synergistic effect on the mould growth and aflatoxin production in poultry diet.

Saccharomyces Biocontrol Mycotoxins Feedstuff Egypt Aspergillus flavus a b s t r a c t A total of 435 samples from feedstuff (130 samples of commercial ration feed storage from 1e30 days, 77 samples of commercial ration stored higher than 30 days, 57 samples from each of, derris, grind mixture, Tibn and wheat bran) were collected from the feed store houses of private farms located at the desert regions of Ras Sudr at South Sinai and Elameria area at Alexandria Governorate, from December 2012 to May 2014. The collected samples were analyzed for fungal growth. The results revealed that, the main moulds observed in the ruminant feeds were Penicillium spp., Aspergillus (A) flavus, Cladosporium spp., Mucor spp., Trichoderma spp., A. niger, Alternaria spp., Rhizopus spp., Fusarium spp., A.fumigates and A. terreus. In addition, the winter season was of higher incidence for moulds isolation than summer season. The most toxigenic aflatoxins secreted by Aspergillus flavus include Aflatoxin B1, Aflatoxin B2, Aflatoxin G1 and Aflatoxin G2. The results of biological treatment of Aflatoxins using Saccharomyces (S) cerevisiae, showed that, the addition of Saccharomyces cerevisiae at a level of (1 Â 10 6 ) cfu.ml À1 and (1 Â 10 9 ) cfu.ml À1 decreased the level of concentration of aflatoxin B1, B2, G1 and G2 and the level of (1 Â 10 9 ) cfu.ml À1 was more efficient in reducing aflatoxins than the lower concentration.