Contamination of cattle feed with molds and mycotoxins

Abstract

The total number of potentially toxigenic molds (fungi), total aflatoxins, zearalenone (ZON), and deoxynivalenol (DON), as well as the joint appearance of ZON and DON have been investigated in 67 samples of cattle feed (concentrate (n=21), silage of whole maize plant (n=18), beet pulp (n=4), brewer's malt (n=2), alfalfa and grass (n=1), alfalfa hay (n=12), meadow hay (n=7), pea and oat hay (n=1), and red clover hay (n=1) originating from private farms from 10 districts of the Republic of Serbia. The total number of fungi per 1 g feed ranged from 0 (silage of brewer’s malt) to 12 x 104 (concentrate). Eight fungi genus species have been identified: Acremonium, Alternaria, Aspergillus, Fusarium, Mucor, Penicillum, Rhizopus and Trichoderma. The presence of ZON (100%) was established in all the examined cattle feed samples, while 98.5% samples were contaminated with total aflatoxins and 92.5% samples were DON positive. The joint appearance of ZON and DON was established in 92.5% samples. ZON was present in the highest average concentration in the sample of alfalfa and grass silage (2477.5 μg kg-1) and in the lowest in beet pulp silage samples (64.9 μg kg-1). Total aflatoxins were established in the highest average concentration in the pea and oat hay silage sample (7.9 μg kg-1) and in the lowest average concentration in beet pulp silage samples (1.6 μg kg-1). DON was detected in the highest average concentration in concentrate samples (694.2 μg kg-1) and in the lowest average concentration in the red clover hay sample (11.0 μg kg-1), while DON was not detected in brewer's malt silage samples (0.0 μg kg-1). In all the examined cattle feed samples, between moisture content (up to 20%) and the concentration of examined mycotoxins, a negative correlation was established (r=-0.26) with total aflatoxins and a positive correlation with ZON (r=0,36) and DON (r=0,60). Furthermore, a positive correlation (r=0.22) was established between ZON and DON concentrations. [Projekat Ministarstva nauke Republike Srbije, br. TR-31023 i br. TR-31053