Mycotoxins Occurrence And Fungal Populations In Different Types Of Silages For Dairy Cows In Spain

In this study, samples of different kinds of silages (maize, grass, alfalfa, sugar beer pulp, immature corn and ryegrass) collected from farms located in four regions of Spain, were analysed to evaluate the occurrence of aflatoxins (AFs) and Fusarium mycotoxins. Their lactic acid bacteria and fungal populations as well as pH and water activity were also studied. Penicillium (4-26%), Geotrichum (2-21%) and Monascus (0.34-3%) were the main fungi identified in all the silages examined. Aspergillus was found in some maize, grass and alfalfa silage samples and Fusarium was only identified in 0.03% of grass silage samples. The incidence of AFs was low (10% of positive samples), being detected in maize, alfalfa and immature corn silage samples. Aflatoxin B1 (AFB1) was only found in maize silage samples (7% of the samples). Fusarium mycotoxins were detected in 40% of the silage samples analysed. These toxins were present in maize, grass, alfalfa, sugar beet pulp and immature corn silage samples, being fumonisins (FBs) the most commonly detected. Maize silage was the most heavily contaminated type of silage (30 positive samples out of 44): FBs were detected in 41% of the samples, 14% presented deoxynivalenol (DON), 23% 15-acetyldeoxynivalenol (15-ADON), and 16% zearalenone (ZEN). Levels of mycotoxins detected in positive samples did not exceed the EU guidance values. The lack of relationship between Fusarium counts and its mycotoxin concentrations suggested that mycotoxin production p...
Source: Fungal Biology - Category: Biology Source Type: research