Bovine Colostrum Supplementation Modulates the Intestinal Microbial Community in Rabbits

BC is a nutraceutical that can modulate intestinal microbiota. This study investigates theeffects of BC diet supplementation on luminal and mucosa-associated microbiota in the jejunum,caecum, and colon of rabbits. Twenty-one New Zealand White female rabbits were divided intothree experimental groups (n = 7) receiving a commercial feed (CTRL group) and the same dietsupplemented with 2.5% and 5% BC (2.5% BC and 5% BC groups, respectively), from 35 (weaning) to90 days of age (slaughtering). At slaughter, the digestive tract was removed from each animal, thenboth content and mucosa-associated microbiota of jejunum, caecum, and colon were collected andanalysed by Next Generation 16SrRNA Gene Sequencing. Significant differences were found in themicrobial composition of the three groups (i.e., beta-diversity: p < 0.01), especially in the caecum andcolon of the 2.5% BC group. The relative abundance analysis showed that the families most affectedby the BC administration were Clostridia UCG-014, Barnesiellaceae, and Eggerthellaceae. A trendwas also found for Lachnospiraceae, Akkermansiaceae, and Bacteroidaceae. A functional prediction as revealed several altered pathways in BC groups, with particular reference to amino acids andlactose metabolism. Firmicutes:Bacteroidetes ratio decreased in caecum luminal samples of the 2.5¼ group. These findings suggest that BC supplementation could positively affect the intestinalmicrobiota. However, further research is needed to establish the optimal administration dose.