Method Development to Determine the Fractal Structures Index into the Broiler Chickens’ Intestines

Microbial communities in the intestines of birds self-organize to carry out joint biochemical actions and extract nutrients from plant substrates. Depending on the feed entering the intestine, the configuration of the microbial biosystem is regularly reconstructed, evenly distributing the enzymatic load between the microbial components. To assess the qualitative and quantitative indicators of these processes, it is proposed to calculate the index of fractal structures of microbial communities existing in the intestines of birds. The technique is based on a fractal analysis of the frequency spectrum of operational taxonomic units (OTU) of microbial communities obtained by the molecular genetic method. Initially, the initial OTU spectrum is converted into an abbreviated spectrum of OTU groups, in which each group combines OTE that are similar in frequency of occurrence. Next, a two-dimensional fractal portrait of the microbial community is constructed, on which each OTU group is represented by a point with coordinates that depend on the frequencies of these groups. A fractal portrait is necessary for conducting a topological analysis of the location of points on it and isolating fractal structures in the microbial community. As a fractal measure, the analysis uses triangles with vertices at the points of the OTU groups. At the same time, the smallest heights of the triangles are selected with the scale of the fractal measure. The construction of triangles and their arrangement in increasing order of scale of the fractal measure allows us to select the first triangles in a row, since they are triangles degenerate into a segment by a straight line. OTU groups included in degenerate triangles are the sought-after determined OTU groups belonging to fractal structures in the microbial community. Their share in the microbial community determines the index of fractal structures (IFS), which also takes into account the uniform distribution of the enzymatic load between OTU. In the experiment, the molecular genetic method of NGS was used to study microbial communities in the intestines of broilers of NGS using two types of probiotics. The obtained frequency-taxonomic spectra were used to calculate the IFS. An analysis of the results showed that probiotics affect the self-organization of microbial communities.