J. Tanprasertsuk and colleagues (2020) conducted a randomized controlled trial to investigate the effects of probiotic supplementation on the gut microbiome of household dogs. A total of 42 dogs were enrolled and randomized to receive either a daily probiotic dose (20 billion CFU consisting of Lactobacillus reuteri, Pediococcus acidilactici, Enterococcus faecium, Lactobacillus acidophilus, Bifidobacterium animalis, Lactobacillus fermentum, and Lactobacillus rhamnosus) or placebo for four weeks.
Metagenomic sequencing revealed no significant effect on α-diversity. However, at week 4, changes in β-diversity at the species level affected approximately 4.3% of gut microbiome composition. Notably, 41 bacterial taxa increased in abundance, with 71% belonging to the Lactobacillus genus. The abundance of E. coli decreased significantly at week 4, but all changes returned to baseline two weeks after stopping supplementation.
Health outcomes showed that dogs receiving probiotics tended to have a lower risk of diarrhoea during the study (0% vs 16% in the placebo group), although no other clinical differences were observed. These findings suggest probiotics may play a modest role in supporting gut stability in otherwise healthy dogs.
The authors note that while effects were small and transient, longer studies in at-risk populations are warranted to determine potential benefits in preventing gastrointestinal disorders.
Source: Tanprasertsuk, J., Shmalberg, J., Jha, A., Perry, L., & Honaker, R. W. (2020). The Effect of Probiotics Supplementation on the Gut Microbiome of Healthy Dogs Assessed Using Metagenomic Sequencing: A Randomized Control Trial. Current Developments in Nutrition.
