Influence of Biological Preservatives on the Change in Nutritional and Energy Values of Legume-Grass Silage Prepared under the Conditions of the Vologda Region

Silage making is a method of preserving feed based on spontaneous lactic acid fermentation under anaerobic conditions. Consequently, the quality of silage can be very variable, and the only way to effectively control the fermentation process is to use biological preservatives. The aim of the research is to give a comparative assessment of the quality of silage from a legume-grass mixture prepared in farms using bacterial starters under the conditions of the Vologda Region. The article presents the results of studies on the effect of biological preservatives «Bonsilazh Forte» and «Bioamid-3» containing different strains of lactic acid and propionic acid bacteria, but without microbial additives on the quality of preserved feed. The highest dry matter yield (271.2 g) was found in silage prepared without biological starter. Despite this, its nutritional value was lower than that of silage treated with Bioamid -3 preservative. The nutritional value of silage fluctuated in the range from 0.85 to 0.89 feed units. The highest values of exchange energy (EE) and crude protein (CP) content were recorded in silage treated with the Bioamid-3 preservative (10.46 MJ / kg and 15.33% of dry matter). The crude fiber content in the studied silages was within 27.78-27.96%. The lowest value of this indicator was characteristic of the feed in the variants with the use of the Bioamide-3 preservative (27.78%), in which it was less than in the other two variants. When analyzing the mineral nutritional value of silages, a slight superiority of silage from a legume-grass mixture with the use of Bioamide-3 preservative was revealed in calcium content over other variants by 5.98- 7.69%. In the variants with preservatives, a decrease in neutral detergent fiber (NDF) to a level of 49.67-51.19% was observed. At the same time, silage without preservatives was characterized by a high content of NDF – 53.87%. A similar pattern was observed for acid detergent fiber (ADF) in the studied feed samples. In all analyzed silage samples, the average active acidity value was 4.24 pH units. The study showed that the use of preservative additives in silage and the absence of such ones provided the content of lactic acid in the total amount of organic acids at the level of 70.20-75.33%, which indicates their high quality, taking into account the existing standards. At the same time, the insignificant presence of butyric acid (0.11%) in silage with the Bonsilazh Forte preservative is not critical.