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Open Life Sci. 2016; 11: 280-286 acetic acid (−46%), ammonium (−59%), ash (−13%) and fat (−24%). Populations of bacteria associated with lactic acid fermentation, moulds, yeasts, enterobacteria and total microorganisms count were also influenced. Both biological and chemical additives can be highly recommended for producing high-quality silages meeting hygienic requirements. In lucerne silage, the chemical preservative showed a stronger effect in achieving the health safety of silage compared to the biological inoculant.Keywords: health safety, silage additives, microorganisms IntroductionBiogenic amines comprise a group of aliphatic, heterocyclic or aromatic bases derived from amino acids. Biogenic amines are present in all feeds that contain proteins or free amino acids, and they also exist in fermentative feeds [1][2][3]. The concentration of biogenic amines (mono-, di-and polyamines) in silage and in the rumen, body tissues and body fluids mainly depends upon the crop at harvest, the ensiling process, the silage and the digestion in the animal. Both the synthesis and chemical structures of mono-and diamines are well documented. The basis for their formation is proteolysis, a naturally occurring process in ensiling consisting in the enzymatic decarboxylation of amino acids by the action of plant proteases and peptidases along with enzymes of various lactic acid bacteria (LAB), clostridia and other bacterial genera [4]. High-quality feedstuffs and proper nutrition are important for all categories of livestock [1][2][3]. High levels of biogenic amines are frequently observed in silages prepared from high-protein forages (lucerne, clover, certain grass species). Some biogenic amines have significant biological characteristics, as they are, for example, tissue hormones (histamine), protoalkaloids (hordenine, gramine) and building DOI 10.1515DOI 10. /biol-2016 Received August 17, 2016; accepted September 21, 2016 Abstract: This experiment examined the influence of two different silage additives of biological (Lactococcus lactis, Lactobacillus plantarum, Enterococcus faecium, enzyme xylanase) and chemical (43% formic acid, 30% ammonium formate, 10% propionic acid, 2% benzoic acid) types on biogenic amines concentration, nutrient content, fermentation process, and microbiologic indicators in lucerne (Medicago sativa) silage after 90 days of fermentation. The biological additive significantly (P < 0.05) increased putrescine (+51%), lactic acid (+11%) and protein content (+11%) in comparison with control silage. It significantly decreased cadaverine (−29%), histamine (−57%), spermidine (−15%), spermine (−55%), acetic acid (−40%), ethanol (−55%), ammonium (−25%) and ash (−9%). After the chemical-additive treatment, greater amounts of histamine and tyramine were recorded. Significant decrease was observed in the concentrations of putrescine (−18%), cadaverine (−55%), spermidine (−47%), spermine (−45%), lactic acid (−16%),

In the production of fermented feed, each crop can be contaminated with a variety of microorganisms that may produce natural pollutants. Biogenic amines, mycotoxins, and undesirable organic acids can decrease health feed safety. The aim of this study was to compare the counts of microorganisms, levels of biogenic amines, and the mycotoxins in forage legumes, and also to compare the occurrence of microorganisms and levels of mycotoxins in green fodder and subsequently produced silage and the influence of additives on the content of natural harmful substances in silage. The experimental plot was located in Troubsko and Vatín, in the Czech Republic. Two varieties of Medicago sativa and one variety of Trifolium pratense were compared. Green fodder and subsequently produced silage reaching up to 23% of dry matter were evaluated and prepared using a bio-enzymatic additive and a chemical additive. Green fodder of Medicago sativa was more contaminated by Enterococci than Trifolium pratense fodder. The obvious difference was determined by the quality of silage leachate. The silage prepared from Medicago sativa fodder was more contaminated with butyric acid. Fungi were present in higher counts in the anaerobic environment of green fodder and contaminated it with zearalenone and deoxynivalenol. Lower counts of fungi were found in silage, although the zearalenone content did not change. Lower content of deoxynivalenol was detected in silage, compared with green fodder. Silages treated with a chemical additive were found not to contain butyric acid. Lower ethanol content was determined, and the tendency to reduce the risk of biogenic amines occurrence was evident. The additives proved to have no influence on the content of mycotoxins.

The aim of the work is to assess the effect of soil contamination of fodder and wilting on the occurrence of fungi in the biomass of alfalfa and subsequently consider the mycotoxin content in alfalfa silage. The alfalfa biomass of Jarka variety, harvested from two experimental plots in different climatic conditions, was evaluated. The total number of microorganisms and fungi were determined in silage biomass and silage. The content of deoxynivalenol and zearalenone in silages was treated with bacterial enzyme inoculant and chemical preservative, which is an acid. The total number of microorganisms was not influenced by the soil contamination of fodder. The occurrence of fungi was increased from 126,807 to 321,992 CFU·g -1 . The total number of microorganisms and fungi was raised by wilting. The occurrence of fungi was increased from 113,909 to 334,890 CFU·g . Deoxynivalenol (increased from 101.9 to 131.5 ppb) was especially determined in alfalfa silage. The content of zearalenone reached up to 0.5442 ppb. The alfalfa silages, produced from wilted silage, contained lower levels (P < 0.05) of deoxynivalenol and zearalenone than alfalfa silages produced from no-wilted biomass. The content of mycotoxins was affected neither biological nor chemical preservative.