Safety assessment and enteric colonization ability of a native canine Lactobacillus murinus strain

The aim of this work was to assess the safety and survival in the canine gastrointestinal tract of a native Lactobacillus murinus strain using an in vivo approach. A spontaneous rifampicin-resistant strain generated from a native Lactobacillus murinus strain isolated from dog feces was used in an in vivo administration protocol performed in dogs. The parental strain had been previously characterized in our laboratory, showing interesting probiotic-related properties. The rifampicin-resistant mutant generally exhibited similar properties to the parental strain. When it was administered to healthy dogs, this strain was able to survive in the canine gut and diverse physiological parameters of the animals did not differ from those assessed in non-treated ones. The present in vivo study using a native canine Lactobacillus murinus strain allowed us to conclude that the assessed strain transiently persisted in the canine gut and is safe for administration in dogs. Results of this assay can contribute to the development of new strategies for health promotion in dogs. Future studies will be carried out to evaluate the potential probiotic strain in vivo in dogs under different clinical conditions.