Molecular characterization of pathogenic mould and yeast isolated from poultry farms with detection of mycotoxins residues

Abstract

In the present study, a total of 50 samples of poultry rations and drinking water in front of the birds (25 for each) were collected from various private broiler farms at Giza governorate. The collected samples were subjected to isolation and identification of contaminant fungi, screening of poultry feeds for aflatoxin B 1 residues, assessment of isolated A. flavus strains for aflatoxin production as well as molecular detection of the aflR gene in isolated A. flavus strains by polymerase chain reaction and molecular detection of the pathogenic Candida lusitaniae. The results showed 100 rations samples were highly contaminated with moulds, but were free from yeasts. The prevalence of mould and yeast from drinking water samples were 48% and 88%, respectively. The total mould count (log 10 CFU/g) obtained from poultry feed samples collected from poultry houses was higher than that of drinking water samples. Total mould count (log 10 CFU/g) in poultry feed samples ranged from 1.8 to 4.4 (log 10 cfu/g) while in drinking water samples ranged from 1 to 1.8 (log 10 cfu/ml). On the other side, it was found that the total yeast count of the examined drinking water ranged from 1.8 and 4. 2 (log 10 cfu/ml). Altogether, one hundred and three isolates representing 9 genera were recovered during this study. The most frequent fungi were from the genus Aspergillus, were A. flavus (17.9 %) appeared to be the most prevalent. The predominant candida species isolated from drinking water samples were C .lusitaniae (21.6 %), C. tropicals (16..2 %), C. pelliculosa (13.5 %), C .famata (10.8 %) and C. krusei (8.2%). Where Torulopsis spp. and Rhodotorula spp were also isolated with a prevalence of 4 (10.8%) and 7 (18.9 %).The aflatoxin B 1 residues were detected in 7 (28%) rations samples with a mean value of 43 µg/ kg. Gamma radiation cause complete inhibited germination of A. flavus spores at 9 kGy.