Metagenomic analysis of the microbiome in the large intestine of cattle with additional inclusion of ultrafine particles Cr2O3

In this work the authors studied changes in taxonomic composition of intestinal microbiome of cattle with inclusion of additional components in a diet. The intestinal microflora was analysed using MiSeq (Illumina, USA) by the method of next generation sequencing (NGS) with the MiSeq reagent kit. With additional introduction of protein component, sunflower cake, into the diet, the dominant phyla also turned out to be Firmicutes (48.2% of the total number of individuals of all species), Bacteroidetes (36.8%), Proteobacteria (12.7%). The inclusion of sunflower cake contributed to a decrease in the number of microbiotas by 23.7% relative to the control (p≤0.05), while the number of representatives of the Ruminococcaceae family relative to the control decreased by 24.1%, while the number of unclassified_Clostridiales in this sample was 19% higher than in the control. Additional introduction of chromium oxide ultrafine particles reduced the number of bacterial sequences relative to the control by 36.9% (p≤0.05). We noted a decrease in the number of the Ruminococcaceae family representatives by 30%, the representative’s number of the families of unclassified Clostridiales, Lachnospiraceae, Bifidobacteriales, on the contrary, increased in experimental group II. The inclusion of ultrafine particles Cr2O3 promoted an increase in the number of Firmicutes by 8.3% relative to the data in group I. The decrease in the α- diversity of the fecal microbiome in the experimental groups also influenced β-diversity, the partial coincidence of the communities in the control and experimental groups, the similarity indices of the Jaccard (IJ) and Sørensen (IS) microbiocenoses were equal to IJ=0.5 and IS=0.67.