Results of mycotoxicological monitoring of cattle feed harvested in the Vologda Region

There has been carried a mycotoxicological research of various feed for cattle to find the most contaminated types of feed and the most common mycotoxins. During the long-term monitoring of feed samples similar in species composition, harvesting and storage conditions to determine the dynamics of the number of mycotoxins over 260 plant samples from a number of the Vologda Region farms were studied, among them 61 samples were examined for the simultaneous content of 4 mycotoxins and 22 samples for the simultaneous content of 5 mycotoxins. The content of the main groups of mycotoxins in harvested feeds using the method of EIA analysis was investigated. A total of 509 analyses were conducted for the period of 2022–2024, including 155 analyses for aflatoxin sum, 132 for ochratoxin-A, 105 for zearalenone, 89 for dioxynivalenol (DON), and 28 for T-2 toxin. The research results revealed that 99 % of the studied samples were contaminated with mycotoxins to some extent: all analyzed samples were infected with aflatoxins and zearalenone, 97 % of the samples were damaged by ochratoxin–A and less than a third of the samples were infected with DON. Moreover, a significant part of the samples was contaminated with two or more mycotoxins. Samples of grain, green mass and haylage contained mycotoxins below the maximum allowable concentration (MAC) level, in hay samples the predominant contaminant was T-2 toxin, the content of which was 9 times higher than the MAC level. The results of analysis of silages of different composition proved that the most contaminated were legume and cereal mono-species silages, so the exceeding of MAC for the sum of aflatoxins on average is 4.1–4.2 times, for ochratoxin-A – 1.1–1.3 times. Monitoring of mycotoxin content showed that samples of cereal-bean silage had an increase in the content of a number of mycotoxins with increasing storage time. For instance, the sum of aflatoxins in three-four weeks after harvesting was 3.27 µg/kg, in 4 months – 5.74 µg/kg, in 10 months – 22.31 µg/kg, a similar trend was observed in the determination of zearalenone. On the contrary, the content of ochratoxin-A slightly decreased. Relatively uniform contamination of the studied samples allows predicting both the composition of contaminants and the degree of their contamination of prepared fodder, which should be taken into account by the relevant specialists of livestock enterprises in the region when developing measures and activities aimed at preventing mycotoxicosis.