Changes in the fecal microbiota in dogs with acute hemorrhagic diarrhea during an outbreak in Norway

J Vet Intern Med. 2021 Sep;35(5):2177-2186. doi: 10.1111/jvim.16201. Epub 2021 Jul 21.


Background: A severe form of acute hemorrhagic diarrhea syndrome (AHDS) occurred in dogs in the Oslo region of Norway during autumn 2019.

Objectives: To characterize the fecal microbiota of dogs with AHDS during the outbreak and compare it to that of healthy dogs from the same period and before the outbreak.

Animals: Dogs with AHDS (n = 50), dogs with nonhemorrhagic diarrhea (n = 3), and healthy dogs (n = 11) were sampled during the outbreak. In addition, 78 healthy dogs from the same region were sampled before the outbreak between 2017 and 2018.

Methods: Retrospective case-control study. The fecal microbiotas were characterized using 16S rRNA gene amplicon sequencing.

Results: Dogs with AHDS had significantly different microbiota composition (R2 = .07, P < .001) and decreased intestinal diversity relative to healthy dogs from the outbreak period (median, 2.7; range, 0.9-3.5 vs median, 3.2; range, 2.6-4.0; P < .001). The microbiota in dogs with AHDS was characterized by a decrease of Firmicutes and an outgrowth of Proteobacteria, with increased numbers of Clostridium perfringens and Providencia spp. Among the Providencia spp., 1 showed 100% sequence identity with a Providencia alcalifaciens strain that was cultivated and isolated from the same outbreak. No Providencia spp. was found in healthy dogs sampled before the outbreak.

Conclusions and clinical importance: Dogs with AHDS had marked changes in fecal microbiota including increased numbers of Providencia spp. and C. perfringens, which may have contributed to the severity of this illness.

Keywords: Norway; canine; dysbiosis; hemorrhagic diarrhea; intestinal microbiota.

MeSH terms

  • Animals
  • Case-Control Studies
  • Diarrhea / epidemiology
  • Diarrhea / veterinary
  • Disease Outbreaks / veterinary
  • Dog Diseases* / epidemiology
  • Dogs
  • Feces
  • Microbiota*
  • Providencia
  • RNA, Ribosomal, 16S / genetics
  • Retrospective Studies


  • RNA, Ribosomal, 16S

Supplementary concepts

  • Providencia alcalifaciens