Gut microbiome and morphometry of quails fed diets containing essential oils

ABSTRACT: One of the greatest challenges in poultry production is maintaining intestinal mucosal barrier integrity and gut microbiota balance. Safe alternative antimicrobials that can regulate the microbial community through animal feed have been the subject of research in poultry production. This study evaluated the effect of Mentha piperita and Melaleuca alternifolia essential oils (EOs) on the gut microbiome and morphometry of broiler quails under normal feeding conditions. The gut microbiome was studied using a completely randomized design consisting of 4 treatments, namely control, bacitracin zinc, and the Eos M. piperita and M. alternifolia, with 8 repetitions and 7 quails per treatment, totaling 224 quails from 1 to 42 days old. The intestinal contents of the slaughtered quails were collected to evaluate the gut microbiome profile of their digestive tract. Gut morphometry was analyzed using a completely randomized factorial design, with four experimental rations for three intestinal sections (4x3) and five replications. The variables studied were villus surface area and height, crypt depth, villus height to cryptdepth ratio (VH:CD), villus-crypt ratio (V:C), villus width to height ratio (VW:H), and height of the intestinal epithelium and musculature. M. alternifolia (50 mg/kg of feed) in the diet of broiler quails improved gut morphometry, similar to the results obtained with bacitracin zinc. This EO also altered the gut microbiome of quails and reduced pathogenic bacterial diversity.