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When the runs hit your runs

Practical management of diarrhea

From Animal Sheltering magazine May/June 2013

Puppies are the epitome of adorableness—until they break with diarrhea. The runs can hit shelter kennels and foster homes alike. This article can help you get your charges back on solid ground. Animals with diarrhea should have a brief physical exam that staff can compare with their initial intake exam; note changes in weight, temperature, and overall body condition.

Afriend’s recent Facebook status, “Anyone want to foster a litter of diarrhea?” made me laugh out loud. When I stopped chuckling, however, I realized that, of the many topics that foster parents, shelter staff, and volunteers seek counsel on, diarrhea tops the list. If you have ever fostered six poop-painting puppies, you know that resolving the issue is no laughing matter!

Certainly diarrhea can be unpleasant to manage, but more seriously, diarrhea can also be a harbinger of serious problems—such as parvovirus or distemper—for a shelter population or group of foster animals. Sometimes, simple changes can resolve the situation, but in severe, unmanaged cases, whole litters can die in hours. Certain pathogens transmitted in stool can even spread to people. Staff and volunteers need the right information to prevent diarrhea and, when it occurs, diagnose common causes, and appropriately care for affected animals.

Catch It Early

Diarrhea generally describes an increased frequency, volume, or fluid content to the stool. The first step in management of diarrhea is recognizing what’s normal and abnormal, and standardizing this knowledge among staff and volunteers.

There are several handy visual charts available that may be useful as training tools. The ASPCA has a guide to poop. Purina has a fecal scoring chart that’s easily found online; some shelters might even choose to be creative and make their own fecal scoring charts for staff training! (Your volunteer photographer will love this assignment.)

Because there are a multitude of potential causes of diarrhea in animals entering shelters and rescues—including diet, infections, stress, and toxins—it is impossible for every animal to be screened or treated for every cause. However, standard wellness measures starting at intake, such as core vaccination; strategic parasite treatment; provision of consistent nutrition; sanitation; segregation; and attention to mental health/enrichment can be very helpful. Organizations that have strong preventive medical protocols will likely experience fewer health problems as a whole, and thus should need to treat fewer animals with diarrhea.

Although many cases will ultimately resolve with minimal medical care, in facilities holding groups of animals, diarrhea should never be overlooked. While any animal can suffer from diarrhea, puppies and kittens are most commonly affected and can quickly become debilitated without care. Additionally, many of the causes are infectious and/or zoonotic. Prompt assessment and response can help protect against population-wide problems.

Therefore, a process should exist for reporting and responding each time animals are observed to have diarrhea, whether they have just entered care or have been living in the shelter for a period of time. This may simply be a medical whiteboard or paper form system, by which an animal’s information is recorded for the medical team to determine next steps. In other facilities, staff may be directed to collect a fecal sample or perform key steps when animals with diarrhea are identified. If an animal is already being treated for diarrhea, a means of recording daily fecal scores can be invaluable for charting response to therapy. Outlining the proper steps for staff in a written protocol helps to avoid confusion and ensure a consistent response.

What to Watch For

Animals with diarrhea should have a brief physical exam performed and documented to compare to their initial intake exam. This should minimally include a weight, temperature, and basic head-to-toe exam. Because the symptoms of diarrhea due to systemic disease and those in an otherwise apparently healthy animal can vary, the way an individual animal is managed depends on these physical exam findings. It can also be very easy to miss early signs of decline, particularly in young animals, if they are not examined.

If serious signs of systemic disease—such as fever, dehydration, vomiting, changes in attitude, etc.—are noted, the animal should be placed in isolation, and veterinary input and further guidance should immediately be sought. Similarly, if multiple animals are affected, or symptomatic humans are noted in proximity to sick animals, a veterinarian should be involved to plan a course of action.

If the animal appears otherwise relatively healthy, there are several steps that can be taken, even when veterinary help may not be immediately available. It’s often useful to attempt to further characterize diarrhea via signs that relate to the region of the intestine where it likely originates, specifically the large or small bowel.Characteristics of large-bowel diarrhea are frequent episodes of small volume, straining, urgency, fresh red blood, and the presence of mucus. Characteristics of small-bowel diarrhea are large volumes, slight increase in frequency, dark/tarry stool, and oily or fatty stool. Those who are caring for animals should take note of these different characteristics. They can be important clues to possible causes of the problem and should be recorded and reported, along with other parameters of the physical exam. For example, large-bowel diarrhea is often seen with parasites, bacterial overgrowth, or an abrupt food change or food intolerance. Some common causes of small-bowel diarrhea include parasites, protozoa (e.g. Coccidia), or viruses.

Testing Protocols

Although clinical signs can help narrow possible causes, shelters need to have a general plan to run diagnostic tests on each animal experiencing diarrhea in order to identify the cause, tailor needed treatment, and minimize further risks. Just as there are many possible causes of diarrhea, there are numerous diagnostic tests that one might select. A good rule of thumb is to screen promptly with tests that will provide useful results for immediate decision-making. Look for problems of highest significance—namely, those animals with the poorest prognosis and highest potential for infectious spread. All organizations should be able to screen animals with a fecal exam and a test for canine parvovirus/feline panleukopenia virus.

A fecal centrifugation and microscopic exam for parasites should be performed on all patients with diarrhea; this is one of the easiest and first diagnostics you should do on any shelter animal with diarrhea. Many shelter medical departments do these in-house (see, but they can also be sent out to most laboratories for a nominal fee. This test should be performed regardless of whether the animal has been recently dewormed, or had a prior negative fecal exam. Internal parasites have complex life cycles, and even when appropriate tests and parasite therapies are used, recurrences, reinfections, and continued shedding of some pathogens are not infrequent. Multiple fecal exams may be required for diagnosis, and empiric treatment is sometimes advisable.

It can be useful to train staff in the proper method of collecting a routine fecal sample from any animal with diarrhea, so that fresh samples can be evaluated promptly. Shelters and rescues can also provide foster homes with this training—foster pets aren’t immune from the issue.

Be prepared to run bedside Enzyme Linked Immunosorbent Assay (ELISA) parvo tests, particularly when puppies and kittens experience small-bowel diarrhea or diarrhea with concurrent systemic signs. The ELISA test is a useful screen for canine parvovirus and feline panleukopenia, both of which have significant population implication for shelters. This test utilizes a fecal swab to detect parvovirus antigen, and can be run in 10-15 minutes. While no test is 100 percent sensitive or specific, positive results on a symptomatic animal are worth heeding. Depending on the timing of the sampling, negative results may occur even when animals are infected, so an ill animal with negative test results may require further testing and care.

Additional screening tests might include rectal cytology, complete blood count evaluations, and feline leukemia/feline immunodeficiency virus testing. More advanced tests might include PCR testing, fecal cultures, radiographs, ultrasounds, necropsy/histopathology, and other evaluations. If the diarrhea persists, a veterinarian can develop an advanced diagnostic plan.

Ongoing Management

If screening tests are inconclusive, otherwise healthy animals with diarrhea may benefit from some simple management before more testing is conducted. Both small- and large-bowel diarrhea may effectively respond to changes in diet. Feeding a consistent, high-quality diet that is appropriate for an animal’s life stage—instead of varied brands of food—can make a difference. Food should be provided in measured amounts based on calories per cup and the animal’s weight ( In some cases, addition of fiber, protein, or other dietary manipulation may be helpful.

Although many cases will ultimately resolve with minimal medical care, in facilities holding groups of animals, diarrhea should never be overlooked.

Prophylactic parasite treatment can also be effective, but should not be considered a replacement for fecal examination. Treatment for roundworms and hookworms, two common and zoonotic internal parasites, as well as for coccidia and giardia, is often successful, particularly in young animals. Because most infectious agents of diarrhea are transmitted via the fecal-oral route, and because stress contributes to illness, bathing affected animals and maintaining a clean, dry, enriched environment is also key.

Ultimately, there are many factors that contribute to gastrointestinal disease. While diarrhea is common and generally not a life-threatening issue, it can be quite unpleasant for both the animals and their caretakers. Strategically utilizing screening tests and following logical management protocols can help to obtain accurate diagnoses and solidify individual animals’ and the population’s health.

About the Author

Miranda Spindel, D.V.M., M.S. is senior director of shelter medicine and development at the ASPCA.