Influence of feed material based on leonardite on broiler chicken’s microbiota, caecal metabolism, blood biochemical parameters, and bone strength

Abstract

The aim of this study was to evaluate the influence of feed material based on leonardite on the caecum microbial profiles, serum indices, and bone strength of broiler chickens (BC). The BC were reared up to 40 days of age. The 60,000 BC were randomly distributed into two groups. Two dietary treatments were compared: (i) basal diet (CON group) and (ii) basal diet containing leonardite at the level of 2kg/1t of feed (LEO group). Metagenomics and microbial profilling analysis of the both groups caecum samples before and after feeding experiment were performed. It was found that the gut of one-day old BC is colonised with bacteria, however, the variety of microorganisms is low, with the most prevalent Escherichia, Clostridium, and Enterococcus. In the gut of 40-days old BC predominant bacteria are Bacteroides, Bransiella, Lactobacillus, Faecalibacterium, and Blautia. According to the data obtained, it could be stated that the supplementation of poultry feed with humic acids increases the amount of probiotic bacteria in BC gut (particularly Bifidobacterium spp.), and, although decreasing of the total number of Lactobacillus species was established, however, variety remained high, compare with CON BC. Significant differences in caecal SCFA, serum Ca, P, Fe, Tibia strength, and caecal pH were not established (p≥0.05). Also, tendensies of the serum hepatic enzymes ALT and AST, as well as cholesterol content decreasing in LEO group (p≥0.05), in compare with CON group, were found.