MICROBIOLOGICAL PROCESSES IN THE LUCERNE HAYLAGE UNDER INOCULATION WITH LACTIC ACID BACTERIA

Abstract

Objective. To characterize the effect of lactic acid bacteria (LAB) on the quantitative and qualitative composition of the groups of microorganisms in the lucerne haylage after their introduction. Methods. Microbiological (cultivation of microorganisms on various media, determination of their viability, measurement of osmotolerance, determination of the amount of lactic acid during cultivation on skimmed sterile milk), microscopic, laboratory experiments on the lucerne haying with a dry matter (DM) content of 46 % and 37 % with and without inoculation with LAB strains, statistical. Results. Lucerne was inoculated with monocultures of Lactobacillus sp. LH42, Lactobacillus sp. LH43, Lactobacillus sp. LH47, L. plantarum КТ-L18/1 osmotolerant strains, which showed tolerance to 2 %, 4 %, 6.5 % sodium chloride in 100 % of cases. The best indicators in terms of active and titrated acidity were found in cultures of Lactobacillus sp. LН47, L. plantarum КТ-L18/1. The inoculation of LAB into the haylage ecosystem at Day 15 of fermentation resulted in an increase in the number of LAB compared to the untreated control. At Day 45 of lucerne haying, the number of LAB decreased and was registered at the level from 1 to 100 billion CFU/g at a 46 % DM content and at the level from 0.01 to 10 billion CFU/g at a 37 % DM content. The greatest development of clostridia in the lucerne haylage in experiments was reported at Day 3 with a sharp decrease in their number at Day 45. The influence of Lactobacillus sp. LH 43, Lactobacillus sp. LH 47, L. plantarum KT-L18/1 on the reduction of the growth of the number of clostridia both at a 46 % and 37 % DM content at the end of the fermentation period was shown. A higher number of yeasts was established at a lower (37 %) content of DM in the haylage. A fungistatic effect was established in variants with LAB inoculation versus the control variant. The relationship between the dynamics of decreasing active acidity (pH) and the dynamics of microbiota development has been shown. Conclusion. Inoculation of the studied strains of lactic acid bacteria into high-protein lucerne haylage mass contributed to an order of magnitude increase in the number of LAB versus the control variant, suppression of the development of clostridia, yeasts and a rapid decrease in active acidity, which confirms data about the effect of LAB-based inoculants on the fermentation of plant raw materials by adjusting the composition of groups of microorganisms