Fecal Transplants for Dogs with Digestive Issues

Fecal transplants can help dogs with chronic digestive problems recover their health by helping them build a more balanced microbiome.

The term alone is a conversation-stopper. Fecal transplants? For dogs? Don’t laugh. Fecal transplants are making headlines as a wonder drug for pets and people.

Forty years ago, when Clostridium difficile (or “C. diff") infections became an epidemic in American hospitals, nothing cured the resulting relentless diarrhea. For most patients, as soon as an effective treatment for C. diff was discontinued, the symptoms returned with a vengeance.

Finally, doctors tried a technique that had been successfully used decades earlier but wasn’t formally adopted because the thought of it made people uncomfortable. When fecal matter from healthy donors was transferred to the colons of sick patients, miraculously, more than 90 percent recovered. Sometimes, their symptoms even resolved within hours and never returned.

Veterinarians who gave fecal transplants to puppies or adult dogs with chronic diarrhea reported similar success rates.

Yes, it sounds distasteful, but fecal transplants are being used to help chronically ill dogs (and humans!) recover from everything from hemorrhagic gastroenteritis (HGE) to environmental allergies.

Transferring microbial material from healthy to sick ruminants, such as cattle, is a long-established veterinary practice, but fecal microbial transplantation, or FMT, is newer to veterinary medicine. A growing number of veterinarians and pet parents are exploring this option for their dogs, and seeing promising results. Understanding your dog’s microbiota and the history of fecal transplants will help you make informed decisions for your best friend regarding the treatment and prevention of gastrointestinal illnesses.

The term “microbiome” was coined by molecular biologist Joshua Lederberg, recipient of the 1958 Nobel Prize in Medicine, to describe the ecological community of commensal (living cooperatively on or within another organism), symbiotic (living in close and mutually beneficial proximity), and pathogenic (capable of causing disease) microorganisms that live in and on the body. 

Today, “microbiome” is an umbrella term used to describe communities of bacteria, viruses, fungi, and other microbes in and on the body. Most intestinal microbes reside in the large intestine, where they are known as the “gut microbiome.”

Bacteria are the most studied of these microorganisms, and the terms “microbiota” and “microflora” describe bacterial communities on mucosal and skin surfaces. The human body contains thousands of species of bacteria, some of which are important to health and others of which can cause disease.

Little attention was paid to the microbiome until testing methods, such as whole genome sequencing, made the National Institutes of Health’s Human Microbiome Project (HMP) and related research possible. The HMP, a five-year study launched in 2008, explored connections between changes in the microbiome and human health and disease.

Dogs have microbiomes, too. In fact, studies have found that people and dogs living in the same household share much of the same microbiome. Complex colonies of microorganisms live in the ears, mouth, respiratory tract, and skin, but most occupy the digestive tract.

A healthy microbiome destroys harmful pathogens, including disease-causing viruses, fungi, bacteria, and parasites. As a result, the microbiome is the immune system’s first line of defense. Differences in microbiomes help explain why some dogs exposed to diseases like parvovirus, distemper, leptospirosis, Lyme disease, canine flu, heartworm, or kennel cough get sick while others remain symptom-free.

“Friendly” or beneficial bacteria secrete chemicals that destroy harmful bacteria and, if they are present in sufficient numbers, colonies of beneficial bacteria starve harmful microbes by depriving them of nutrients and space.

In addition, the microbes in a healthy microbiome can bind to toxins, such as allergens and cancer-causing substances, removing them from the body before they can cause health problems. 

The mucus membrane that lines the gastrointestinal tract from the esophagus to the colon contains lymphocytes and macrophages, which are different types of white blood cells that attack or disable agents of infection. This membrane, the gut-associated lymphoid tissue (GALT), prevents digestion-improving bacteria from penetrating other tissues or entering the bloodstream, where they can cause damage.

A healthy microbiome not only improves a dog’s digestion, but also manufactures some nutrients, including thiamin (vitamin B1), cobalamin (vitamin B12), and short-chain fatty acids that help your dog absorb minerals such as calcium, iron, and magnesium.

In addition, the microbiome helps regulate the body’s endocrine system and metabolism, and there are links between the microbiome and mental health. In short, the microbiome affects nearly every aspect of your dog’s health and happiness.

At about 15 years old, Yuki (above), owned by Dr. Holly Ganz (Founder of Animal Biome), began exhibiting clinical signs of hemorrhagic gastroenteritis (HGE) nearly once a month. She was able to eat only a chicken and rice-based kibble and one treat that contained only chicken. Other foods would trigger bouts of bloody diarrhea and it would take weeks for her stools to become normal.

Starting in late April 2017, Yuki was given Animal Biome’s Gut Restore for Dogs. Capsules were given twice a day for four weeks.

While taking the capsules, Yuki’s stools improved in consistency and continued to improve in the following weeks. Subsequently, Dr. Ganz was able to reintroduce additional protein sources and treats into Yuki’s diet. Gut Restore stabilized her symptoms, and she continued with solid stools long after. 

Below are some of the results of Yuki’s microbial analyses. The complete report shows how Yuki’s microbiome changed after receiving fecal transplants, and compares the analyses from Yuki’s fecal samples taken before and after treatment with average values of samples taken from healthy dogs. Each bacterial type found in the samples is described and its presence in the dog’s microbiome is discussed. 

The necessary ingredients for a successful fecal transplant are a healthy, well-screened donor and a method for transferring material from donor to patient.

In humans, donors have often been family members or close friends. In the past few years, donor banks have been created to store fecal matter from volunteers. These volunteers must be healthy, with no recent antibiotic use and no bowel disease, and who are tested for conditions including blood-borne pathogens and parasitic infections.

Human clinics mix donor feces with sterile saline solution, then homogenize and/or filter the mixture to remove particles that might clog equipment. Both fresh and frozen material has been shown to be effective. The donor’s stool can be administered orally through a nasogastric tube, or rectally during a colonoscopy. The latter method is often preferred because it administers the fecal suspension directly into the ileum (the small intestine’s final and longest section) and the entire colon.

Because fecal material has the potential to pass pathogens or imbalanced microbes, screening the fecal donor is critical before the material is transferred to a sick dog. Animal Biome sets the standard for donor screening, requiring no current or prior health issues or behavioral issues; a healthy body weight; no recent antibiotic use; the absence of pathogens and parasites; and a diverse, well-balanced microbiome. 

FMT treatment sounds like a miracle cure, but it doesn’t work for every patient. In some cases, the effects of FMT have been temporary, or the procedure had to be repeated because the introduced fecal material was not effectively absorbed, or the transplanted bacteria were overwhelmed by existing medical conditions.

The cost of FMT varies according to the methods used, but between testing procedures, sedation, veterinary consultation, and donor screening, the cost in the US can range from $500-$1500.

The term “dysbiosis” describes weakened or depleted beneficial microbes such as those that make up the microbiome. As soon as the body’s population of beneficial microbes declines, pathogens begin to crowd them out, often resulting in nutritional deficiencies and illnesses, including inflammatory bowel disease (IBD). The main symptoms of inflammatory bowel disease in dogs are diarrhea, vomiting, and weight loss.

What causes dysbiosis? While most of the blame goes to antibiotics – the wonder drugs that destroy beneficial as well as harmful bacteria – researchers list additional contributing causes such as genetically modified or highly processed foods, pesticides, chemical preservatives, prescription drugs, and the stresses of modern life.

Dysbiosis contributes to leaky gut syndrome, in which undigested or partially digested food particles move through the digestive tract’s mucous lining and enter the blood stream. This can happen when the mucous lining shrinks and thins, leading to injury and inflammation. Leaky gut syndrome has been blamed for a variety of symptoms and illnesses, including food allergies, hot spots, skin irritations, yeast infections, diarrhea, constipation, inflammatory bowel disease, autoimmune disorders, joint pain, imbalances involving the liver or pancreas, thyroid problems, weight gain, diabetes, slow metabolism, and low energy.

The methods most frequently suggested for reversing dysbiosis include avoiding antibiotics, pesticides, prescription drugs, and toxins, all of which can damage the microbiome. Feeding fresh, whole foods rather than sterilized processed foods is recommended because fresh foods contain bacteria that support the microbiome. Daily outdoor exercise supports the microbiome by exposing a dog to naturally occurring microbes. Probiotic supplements are often recommended, although dog parents must take care to select products that survive the stomach acid. Other probiotic sources include foods that are themselves rich in beneficial bacteria, such as naturally fermented vegetables. Foods and supplements containing prebiotics, or fiber that nourishes beneficial bacteria, support the microbiome as well.

As effective as probiotics can be in preventative medicine, when a dog has inflammatory bowel disease, probiotics may not be enough. In fact, there is little scientific support for their therapeutic use in canine IBD.

Human IBD is difficult to diagnose and often involves intestinal biopsies, but identifying IBD in dogs should become easier thanks to a unique pattern of microbes that accompanies the illness. In October 2016, the journal Nature Microbiology reported that researchers at the University of California San Diego School of Medicine analyzed fecal samples from dogs with and without IBD and discovered that they were able to predict which dogs had the disease with more than 90 percent accuracy. While there is not yet a veterinary test for canine IBD, diagnosing the illness with a simple stool sample may be possible in the future.

While there are no clinical trials proving any of the following claims, veterinarians who use FMT believe that it does far more than repair a dog’s digestion.

For example, Dr. Thomas Borody considers FMT a possible treatment for humans with Parkinson’s disease, autism, and rheumatoid arthritis, and other physicians claim it may help prevent or treat Alzheimer’s disease, depression, acne, type 2 diabetes, cancer, and more.

In many cases, such theories are based on observations that may be coincidental, such as when a patient with rheumatoid arthritis is treated with FMT for a digestive disorder and the arthritis symptoms diminish along with the patient’s diarrhea.

Scientists and veterinarians have made amazing progress when it comes to understanding FMT and its potential benefits. And it's encouraging to know that we can expect to learn much more in the years ahead. 

With their need for special equipment and sedation, Fecal Microbiota Transplantation procedures can be expensive and time-consuming. Wouldn’t it be simpler just to give a dog some pills to swallow?

Yes, says microbial ecologist Holly Ganz, PhD and founder of Animal Biome, a company that analyzes the microbiomes of cats and dogs and offers relief in the form of healthy fecal material in capsules. “Our microbiome assessment kits can help you and your veterinarian determine whether your pet’s disorder is linked to an imbalanced gut microbiome,” she explains.

The test identifies all of the bacteria in a dog’s fecal sample, establishes a baseline profile of the dog’s gut health, and compares it to the microbiome profiles of other dogs. Learning whether a dog’s digestive disorder is linked to a bacterial imbalance, or discovering an imbalance before it affects the animal’s health, can help veterinarians and caregivers make appropriate changes in diet, lifestyle, or medical treatment.

For dogs with symptoms of inflammatory bowel disease or similar disorders, Animal Biome offers capsules containing fecal matter from donor dogs who are screened for health, age, fecal consistency, behavior, and microbiome composition based on DNA sequencing. Donors regularly go outdoors for walks, have not had antibiotic treatment in the prior six months, have diverse microbiomes, and are at a healthy weight

Do capsules work? In a pilot study run by Animal Biome, it was found that about 80% of dogs experienced a significant improvement in their digestive symptoms. 

In a 2014 study, 20 patients who had had at least three episodes of recurrent C. difficile infection took 15 stool capsules from pre-screened, healthy donors over a two-day period. In 14 of the patients, diarrhea resolved after the first treatment. The remaining six patients were treated again, and four of them recovered. None of the successfully treated patients experienced a recurrence of symptoms in the following eight weeks, resulting in a 90 percent success rate.

Invasive methods do not need to be used to deliver healthy stool. “The study showed you can use frozen donor stool successfully and safely,” says the study’s co-author, gastroenterologist George H. Russell, MD, MS.

Early proponents of so-called “evolutionary” or “biologically appropriate raw diets” have noted that the droppings of healthy herbivores, including deer, elk, sheep, and cattle, are a treasure trove of probiotics, prebiotics, and other nutrients. In her Complete Herbal Handbook for the Dog and Cat (Farrar, Straus and Giroux, 1991), Juliette de Bairacli Levy wrote, “Dogs should never have their natural instincts thwarted in the matter of diet. They should not be prevented from eating the droppings of grass-fed cattle and horses, from which they can get many vital elements derived from the herbage on which the animals have grazed and in a form easily assimilated by the dog.”

In his popular book, Give Your Dog a Bone: The Practical Commonsense Way to Feed Dogs for a Long Healthy Life (Warrigal Publishing, 1993), Australian veterinarian Ian Billinghurst reminded readers that all dogs are scavengers. “They receive valuable nutrients from material we humans find totally repugnant,” he said, “things like vomit, feces, and decaying flesh… Feces are a highly valuable food consisting of the dead and living bodies of millions upon millions of bacteria.”

The manure of deer, elk, cattle, sheep, geese, and other grass-eating animals contains B-complex vitamins, vitamin K, minerals, beneficial bacteria, essential fatty acids, enzymes, antioxidants, and fiber.

The obvious problem with free-range poop-eating is that the donors of ingested fecal matter might be ill, have an imbalanced or damaged microbiome, carry a contagious disease, or contain parasites such as Giardia, Coccidia, roundworms, tapeworms, or whipworms. Livestock droppings may also contain medications such as ivermectin used for deworming that could make your dog sick.

For farm dogs and dogs in rural areas, the benefits of eating manure probably outweigh the risks, but coprophagia (a dog’s habit of eating its own stool or that of other dogs) can cause problems. Eating their own stool won’t expose a dog to new microorganisms that could bring balance to his microbiome – and consumption of the droppings of dogs with an unknown health status is inadvisable.

One report from the March 24, 2016 Bradenton Herald in Bradenton, Florida, describes the work of Kevin Conrad, DVM, at Southeastern Guide Dogs in Palmetto, Florida. Dr. Conrad had been looking for a better way to treat dogs with recurrent diarrhea when he discovered FMT. “We see 250 dogs a year, and there were a lot of repeat offenders with symptoms not going away,” he said. “We’d either repeat antibiotics or adjust their feeding. It could take days, weeks, or months to get one dog feeling better, and I knew there had to be an easier process.”

Dr. Conrad took stool from healthy dogs, screened it by culturing microbes to check for harmful bacteria, then liquified the stool and injected it into the intestines of sick puppies with a rectal tube. Within 12 to 24 hours, their symptoms began to clear. He later used the method to treat adults and pregnant dogs.

“What we tried is to do a fecal transplant on a pre-litter mom while she is pregnant, and she’s dropping a whole litter of puppies without diarrhea issues,” he said, “So now we are not only treating it but preventing it.”

At Angell Animal Medical Center in Boston, Massachusetts, Erika de Papp, DVM, considers FMT “an exciting avenue of potential therapy for chronic enteropathies.” She cites a study conducted at the Ontario Veterinary College at the University of Guelph in Canada in which FMT successfully treated dogs and cats for chronic diarrhea that did not respond to  standard therapies of diet manipulation, antibiotics, anti-inflammatories, or probiotics. Donor stool was screened for parasites, Giardia, Salmonella, Campylobacter, C. difficile, and (in the case of cats) Tritrichomonas foetus.

Patients received an enema to clear their intestines before receiving FMT and then a fecal suspension delivered via enema was retained in the colon for 45 minutes. The patients’ fecal microbiomes were evaluated before and after FMT through 16S rRNA gene product sequencing. Within 24 hours, their symptoms improved, and within 48 hours of treatment, the patients’ microbiomes resembled those of their donors rather than their own stool.

Noting that the success of FMT with human patients has helped the procedure gain general acceptance in the veterinary community, Dr. de Papp said, also noting that she "[hopes] we can convince our veterinary clients that this is not an entirely unpalatable treatment.”

For information about ongoing, planned, or completed clinical trials involving dogs and the microbiome, search online for “clinical trials” and “canine fecal transplants” or “canine microbiome.”

For information about Fecal Microbial Transplantation research in general, visit the Fecal Transplant Foundation and The Power of Poop.

This article adapted from an article originally published in the Whole Dog Journal.