ECOLOGY OF RUMINAL MICROORGANISMS UNDER THE INFLUENCE OF QUERCUS CORTEX EXTRACT

Abstract

The study was performed for assessing the elemental status and the bacterial composition of the rumen fluid microflora in cattle after incubation in vitro with quercus cortex extract and exogenous enzymes. The mixture of alfalfa hay, sudan grass and concentrates (60:40) was used as the substrate. The results showed that in the protozoa a decrease in such elements as p, na, ca (p≤0.05) was observed when substrate with enzyme was added. The level of essential elements in bacteria three hours after the incubation together with the enzyme changed similar to the protozoa, except for copper, the content of which increased two times (p≤0.05). The introduction of quercus cortex extract into the substrate with the enzyme preparation three hours after the incubation promoted a significant increase in iron, manganese and cobalt content in the protozoa (p≤0.05). Unlike other variants, incubation of the substrate with the enzyme together with the extract increased the number of representatives of the taxa firmicutes by 13.2%, bacteroidetes - by 13.4% (p≤0.05) against the background of a slight decrease in proteobacteria, saccharibacteria and fibrobacteres. An increase was observed in the number of microorganisms belonging to the taxa clostridia (by 23.7%; p≤0.05) and bacteroidia (by 13.4%; p≤0.05). The
biosensor based on b.subtilis on samples with the extract reacted by quenching the luminescence by 60% on the 5th minutes and by 32% on the 60th minute contact. Thus, the chemical composition of oak bark extract significantly influenced the elemental profile and the bacterial composition of cattle rumen microorganisms.