The presence of bacteria in the blood has been often associated with an infection. However, recent studies have found bacterial DNA in the blood of healthy subjects. Currently, several hypotheses support the existence of a blood microbiome also in healthy hosts.
Objectives
The aim of this study is to characterize the blood microbiome of healthy dogs and dogs with chronic enteropathies (CE), and to correlate targeted microorganisms observed in blood and stool samples with ongoing disease. The final purpose is to assess a list of detectable blood bacteria correlated with different levels of the gut inflammation, that are possible to evaluate during a chronic pathology.
Animals
17 healthy dogs and 19 CE dogs.
Methods
Blood and fecal samples were collected from healthy and diseased dogs and analyzed for the full 16S rRNA gene, though PacBio long-read high-throughput sequencing.
Results
Alpha and beta diversities of fecal microbiome were significantly different between the two groups of dogs. Principal components analysis revealed that healthy and sick subjects were significantly clustered, for both blood and fecal microbiome samples. Some of the taxa shared between blood and stool samples were further analyzed through quantitative Real Time PCR, in order to get the true picture of their abundances. Further studies are needed to confirm the origin of the blood microbiome.
Conclusions
The characterization of a core microbiome in the blood of domestic dogs has potential for use as a diagnostic tool to monitor for the development of gastro-intestinal disease.
