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The aim of the study: The aim of this study was to investigate the hygienic quality of raw material and silage (grown and produced in Lithuania) and risk assessment for animal health. Objectives of the study: 1. To determine and compare hygienic parameters and concentrations of mycotoxins in raw materials and silage at various stages of fermentation produced using different farming systems. 2. To find correlations between hygienic and chemico-fermentative parameters of silage. 3. To analyse the self-control concentrations of silage forage in 2011–2015 and concentrations in problem batches of silage delivered to the Animal Welfare Research Laboratory for mycotoxin analysis. 4. To evaluate the impact of various mycotoxins and silages contaminated with mycotoxins on different systems of the organisms using different tissue cultures in vitro. 5. To evaluate the impact of naturally mycotoxin-contaminated fodder on the milk cows in vivo and the efficacy of the preparation for detoxification. 6. To study the possibilities to use plant extracts for improvement of hygienic quality of silage. Actuality and novelty of the work: As was mentioned, so far Lithuania lacks investigations about the hygienic quality of silages and raw materials, i.e. about the concentrations of microorganisms, including fungi and secondary metabolites, in them. The in vitro and in vivo data about the impact of mycotoxins on animal health also are lacking. The present study is the first of this kind in Lithuania. Concentrations of mycotoxins in the samples of maize and silage at different fermentation stages collected from farms in different Lithuanian regions were determined. The present paper contains a survey of the distribution differences of the secondary metabolites of fungi in the round bales of perennial grass silage in the farms applying different farming systems. The changes of the hygienic quality of silage and concentrations of mycotoxins in the raw material and at different fermentation stages applying different ensiling technologies were determined. The study is especially relevant for evaluation of the quality and safety of fodder from organic farms because few works in this field of research have been carried out. Knowing at what stage of fermentation the greatest changes of silage quality (mycotoxin concentrations in particular) occur it would be possible to avoid their getting into the animal organism or at least to reduce the negative impact of mycotoxins using appropriate detoxification measures. The present study shows the ways of mycotoxins getting not only into the animal organism but also into the human organism through the food chain what helps to evaluate the seriousness of the health risks. The obtained results will fill some gaps of the data necessary for establishment of the maximal concentration limits of mycotoxins in fodder. The correlation links between the hygienic and fermentation parameters, which are important for analysis of hygienic changes and patterns of mycotoxins formation in the technological process from the moment of packing the raw material until the end of storage, were searched for. The use of medicinal extracts in vitro as a measure for stabilization of hygienic level was evaluated. |
