Effects of a Novel Prebiotic and Postbiotic Dietary Supplement on Gut Microbiota, Intestinal Barrier Markers, and Inflammation in Healthy Dogs

Although prebiotics and postbiotics support gastrointestinal health, evidence for their combined effects in dogs remains limited. This study evaluated a novel prebiotic and postbiotic supplement in healthy dogs undergoing a dietary transition. Thirty-six healthy adult dogs were randomly assigned to control group (CON, high-protein basal diet with placebo chew) or treatment group (TRT, the same basal diet with chew containing prebiotics baobab fruit pulp and acacia gum and postbiotics inactivated Lactobacillus acidophilus and selected yeast fractions) for a 28-day formal trial following a 7-day adaptation period. The primary outcomes evaluated included clinical fecal scores, specific biomarkers of intestinal barrier function and inflammation, fecal short-chain fatty acids, and microbiota structure. Following the 7-day adaptation, formal trial baseline, fecal scores were already within the healthy range and remained optimal without differing between groups throughout the study. Compared with CON, the TRT group showed lower fecal calprotectin and serum diamine oxidase levels, and higher fecal butyrate (p < 0.05). Metagenomic analysis revealed increased abundances of Bacteroidota, Oscillospiraceae, Prevotellaceae, and Prevotella in TRT (p < 0.05). Overall, in healthy dogs, this supplementation was associated with favorable microbiota modulation and modulated biomarkers of intestinal barrier and inflammation within normal ranges, without altering clinical fecal endpoints.