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%),