Enumeration and identification of Aspergillus group and Penicillium species in poultry feeds from Argentina

A total of 180 samples of poultry feeds were collected during 1996 and 1997 from different factories in the south of the province of Cordoba-Argentina . They were examined fur the occurrence of Penicillium spp. and Aspergillus group species. Likewise, the capacity to produce aflatoxins by the Aspergi llus section flavi group was determined. The predominant species of Aspergi llus were A. flavus and A. parasiticus. For Penicillium spp., P. brevicompa ctum, P. purpurogenum and P. oxalicum were identified. Less frequently isol ated were A. candidus, A. fumigatus, A. niger; A. orizae, A. parvulus, A. t amarii, A. terreus, and P. expansum, P. funiculosum, P. minioluteum, P. pin ophylum, Fl restrictum, P. variabile and others. The mean value counts rang ed from 1 x 10(3) to 9.5 x 10(4) CFU/g for the Aspergillus spp. and from 1. 2 x 10(3) to 2.5 x 10(5) CFU/g for the Penicillium spp. When cultured on au toclaved rice kernels for 1 week in the dark at 25 degrees C, mycotoxin pro duction by strains of A. flavus was as follows: 21 of the 45 assayed strain s (47%) produced aflatoxins. From them, 24% of the isolates produced AFB(1) and AFB(2) with levels from 181 to 14 545 and 6 to 3640 mu g/kg respective ly. Only 10 strains produced AFB(1) with levels from 10 to 920 mu g/kg. Fif ty percent of the A. parasiticus strain was toxicogenic; six aflatoxicogeni c profiles were identified. Only 10% of the strains produced all of the afl atoxins. These results showed that a potential exists for the production of mycotoxins by the Aspergillus section flavi and the Penicillium spp. They also suggested an association of mycotoxicosis with poultry feeds in Argent ina.