Microbiome Responses to Fecal Microbiota Transplantation in Cats with Chronic Digestive Issues

Abstract

There is growing interest in the application of fecal microbiota transplants (FMTs) in small animal medicine, but there are few published studies that have tested their effects in the domestic cat (Felis catus). Here we use 16S rRNA gene sequencing to examine fecal microbiome changes in 46 domestic cats with chronic digestive issues that received FMTs using lyophilized stool that was delivered in oral capsules. Fecal samples were collected from FMT recipients before and two weeks after the end of the full course of 50 capsules, as well as from their stool donors (N = 10), and other healthy cats (N = 113). The fecal microbiomes of FMT recipients varied with host clinical signs and dry kibble consumption, and shifts in the relative abundances of Clostridium, Collinsella, Megamonas, Desulfovibrio and Escherichia were observed after FMT. Overall, donors shared 13% of their bacterial amplicon sequence variants (ASVs) with FMT recipients and the most commonly shared ASVs were classified as Prevotella 9, Peptoclostridium, Bacteroides, and Collinsella. Lastly, the fecal microbiomes of cats with diarrhea became more similar to the microbiomes of age-matched and diet-matched healthy cats compared to cats with constipation. Overall, our results suggest that microbiome responses to FMT may be modulated by the FMT recipient’s initial presenting clinical signs, diet, and their donor’s microbiome.

Microbiome Responses to Oral Fecal Microbiota Transplantation in a Cohort of Domestic Dogs

“…Interestingly, the fecal microbiomes of FMT recipients were not significantly predicted by clinical signs; that is, dogs with diarrhea did not have fundamentally different microbiomes from dogs with vomiting and/or constipation. This contrasts findings from a recently published study conducted in cats that took oral capsule FMTs for their chronic digestive issues [ 26 ]. That study reported that the fecal microbiomes of cats with diarrhea differed from the fecal microbiomes of cats with constipation and/or vomiting.…”

“…No two FMT participants had identical preFMT or postFMT microbiomes. Similarly, a recently published study in cats also reported individual-specific microbiome responses to oral FMTs [ 26 ].…”

“…Several factors could be modulating how FMT recipients and their microbiomes respond to FMT, such as prior diagnoses, prior antibiotic exposure, or the dog’s diet and lifestyle. For example, a recently published study found that microbiome responses to oral FMTs in cats with chronic digestive issues were individual-specific and correlated with host clinical signs and diet [ 26 ]. Nonetheless, this type of information is unknown for dogs.…”

“…Certain groups of bacterial taxa may also be more likely to be transferred from stool donors to their recipients. In cats receiving oral FMTs for chronic digestive issues [ 26 ], the most commonly engrafted ASVs belonged to bacteria in the genera Peptoclostridium , Bacteroides , Prevotella , and Collinsella . In humans, strain engraftment for patients with recurrent C. difficile (rCDI) infection was impacted by the abundance and phylogenetic breadth of both the donor’s bacteria and the FMT recipient’s bacteria [ 27 ].…”

Gut microbiota in cats with inflammatory bowel disease and low-grade intestinal T-cell lymphoma

“…Changes in the bacterial composition of the gut microbiota were also described, with a decrease in the abundance of Clostridium perfringens and an increase in the abundance of Blautia spp., Ruminococcus torques and Ruminococcus gnavus ( Lee et al, 2022 ). Oral fecal microbiota transplant capsules were prospectively administered to 46 pet cats with chronic gastrointestinal signs, leading to partial stool donor bacterial engraftment ( Rojas et al, 2023 ). The fecal microbiota of responders tended to become more similar to the fecal microbiota of healthy cats ( Rojas et al, 2023 ).…”