Mycoflora of Poultry Feeds and Mycotoxins Producing Potential of Aspergillus Species

The aim of this study was to determine the mycoflora of poultry feeds and evaluate the aflatoxin and ochratoxins producing ability of isolated Aspergillus species. One hundred and nineteen samples of commercially prepared and farm mixed feeds were collected during 20052007. The samples were inoculated on potato dextrose agar, Czapek dox solution agar, Czapek yeast autolysate agar and yeast extract sucrose (YES) agar. Mycotoxins analysis of plate cultures was performed by a HPLC technique. Fungal contamination of commercially prepared and farm-mixed and total feeds was 69.66 and 83.33 and 73.10%. Aspergillus species were the most predominant followed by Penicillium, Fusarium and Alternaria. Among the Aspergillus isolates, A. niger aggregates (37.74%) was most frequently isolated species followed by A. flavus (22.64), A. ochraceous (16.98%), A. parasiticus (13.21%), A. carbonarius (3.77%), A. fumigatus (3.77%) and A. oryzae (1.89%). Proportion of toxigenic fungi among Aspergillus isolates was 73.58%. Aflatoxigenic isolates of A. flavus and A. parasiticus were 83.33% and 85.71% while ochratoxigenic isolates of A. carbonarius, A. niger aggregates and A. ochraceous were 50, 65 and 100%, respectively. On YES medium toxigenic Aspergillus isolates produced aflatoxins varying from 0.00095 to1.9807 μg/g whereas ochratoxin A production varied from 0.00136 to 16.7168 μg/g.