Nutritional management of IBD and colitis in pets

It is relatively common that in practice we see patients with some form of gastrointestinal disease or disorder. With the growing body of research into the gut microbiome and how we can improve the health of pets with gastrointestinal illnesses, today’s blog looks into what we can do for IBD and colitis patients with diet.

But first, what is IBD and colitis, and how are they different?

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Inflammatory Bowel Disease

Inflammatory Bowel Disease is characterized by chronic inflammation of the small and large intestines which disrupts the contractions of the intestinal muscles. The contractions become irregular and cause mucus and toxins to collect in the intestines, trapping gas and faeces. This results in bloating, distension and constipation but also sometimes alternates with diarrhea. The cause is unknown, but can be related to food allergies or bacterial, viral or parasitic infections and can come in a variety of different forms affecting different parts of the gastrointestinal tract. In the small intestine, there are three forms being lymphocytic-plasmacytic enteritis (LPE), eosinophilic enteritis and eosinophilic gastro-enteritis (EGE). While these are generally considered a true IBD, patients may have combinations of both and any part of the GI tract can be affected, including the stomach.


Colitis on the other hand, is more specifically describing the inflammation of the colon but does share some characteristics of IBD. The biggest difference is colitis can be triggered by stress and anxiety, much like humans suffering from IBS and is most often associated with blood and mucous in stool. Affecting mainly the large intestine, there are four main forms of colitis; lymphocytic-plasmacytic colitis, eosinophilic colitis, histiocytic ulcerative colitis (HUC), and regional granulomatous colitis. Another important chronic enteritis, that may fall under the umbrella of colitis, is the so-called food-responsive diarrhoea (FRD). This disease is especially important because it is often included in the differential diagnosis of IBD, and can be used to distinguish between the two based on how the patient responds to dietary management.

What is the cause?

Both IBD and colitis share similar causes, with the main difference being stress – this is a significant contributor to colitis and can trigger flare ups of the condition, whereas IBD isn’t usually affected by stress and is more physiological, autoimmune or genetic in cause. Some causes of IBD and colitis are;

  • Intestinal parasites such as roundworms, whipworms, hookworms, and Giardia 
  • Stress
  • Pancreatitis
  • Dietary intolerance or allergy
  • Dietary indiscretion, such as eating grass, garbage, or people food
  • Bacterial infection
  • Viral infection 
  • Genetics

What are the Key Nutritional Factors?

When looking at how we can manage these conditions with diet, we must consider the Key Nutritional Factors. While the KNFs are very similar between the two conditions, the main difference is for colitis the inclusion of electrolytes; this is due to the fact that both the large intestine’s ability to absorb electrolytes is impaired, and the diarrhea that is generally associated with colitis can cause significant losses of electrolytes. For IBD, there’s a greater focus on hydrolysed foods and novel proteins, as we discussed above, allergies can be a trigger of IBD episodes.

Key Nutritional Factors for IBD (Small Animal Clinical Nutrition, 2020)
Key Nutritional Factors for Colitis (Small Animal Clinical Nutrition, 2020)

How do we manage IBD and colitis in pets?

Nutritional management forms a huge part of the management of these conditions in pets. Following the above Key Nutritional Factors, there’s a few diets that we can look at using to provide symptomatic and functional relief of the conditions.

Hydrolysed diets: These diets help in two ways. First, some pets with IBD or colitis may have allergies that can trigger their symptoms and have shown promising results in managing IBD in pets. Second, hydrolysed diets are broken down through enzymatic digestion, which means they may be easier to digest and process for pets with gastrointestinal disorders – reducing the energy they need to expend on digesting the food and maximising the nutrition that is absorbed by the dysfunctional gut. Examples of these diets include Hills Z/d, Royal Canin Hypoallergenic, Royal Canin Anallergenic, or ProPlan HA.

Gastrointestinal diets: These diets are different from hydrolysed diets in that they aren’t designed to manage allergies. Instead they are aimed at restoring the gut’s normal function, providing an enriched level of nutrients to replenish what is lost through diarrhea, vomiting or constipation and providing symptomatic relief of gastrointestinal issues. Examples of gastrointestinal diets; Hills I/d, Royal Canin Gastrointestinal, or ProPlan EN.

Prebiotics and Probiotics: I’ve written about these supplements before but I’ll briefly explain how these supplements work to help pets with IBD and colitis; with prebiotics, this is usually a fibre source that provides nourishment to the good bacteria and intestinal cells that line the gut. With probiotics, these are strains of good bacteria that are introduced to repopulate the gut microbiome. Recent studies have shown that the gut microbiome in dogs with IBD and colitis have altered gut microbiomes, and do not have the same microbial strains that are present in healthy pets (Xenoulis, 2008) which is why adding supportive gut microbiota into the GI tract can help reboot the digestive system, and the prebiotic fibre can keep the bacteria sustained and prevent future flare ups of symptoms. Probiotic supplements include products such as ProN8Ture, FortiFlora, SynBiotic, Digesticare and Visbiome. With prebiotics, some probiotic supplements already include a prebiotic, or you can use human fibre supplements such as Metamucil, or using psyllium husk powders. The other option is using enriched diets that contain prebiotics, such as Hills Gastrointestinal Biome.

Medications in conjuction with nutritional management: sometimes the use of steroids, antacids and gastroprotectants may be necessary to support the digestive system’s normal function so that it’s able to respond effectively to nutritional management. It’s also important to ensure these pets are free from parasites, as they can contribute to the condition, so make sure they are on a regular prevention protocol for intestinal worms and ectoparasites such as fleas and ticks. Ask your vet for the right combination of medications and preventatives for your pet.

While we cannot cure Inflammatory Bowel Disease or Colitis, we can manage it and improve the quality of life of pets that are suffering with the conditions. It takes quite abit of commitment to get to a place of management, as any pet parent of these patients will tell you, but it is achievable and we can get there. If you have a pet suffering from these conditions, please know there is a light at the end of the tunnel!


Xenoulis, P.G., Palculict, B., Allenspach, K., Steiner, J.M., Van House, A.M. and Suchodolski, J.S., 2008. Molecular-phylogenetic characterization of microbial communities imbalances in the small intestine of dogs with inflammatory bowel disease. FEMS microbiology ecology, 66(3), pp.579-589.

One thought on “Nutritional management of IBD and colitis in pets

  1. Great information! I have a great dane puppy that turns 1 tomorrow that is having frequent GI problems. After 2 emergency vet visits last month (to rule out blockage or bloat), seeing an internal medicine specialist and various primary care clinics, we are still struggling to figure out why it has always been so hard to get this guy to eat and why it seems to be getting worse. The 1st ER visit a month ago showed free fluid in the abdomen and multiple inconclusive ultrasounds that improved over his 3-1/2 day stay and left us with no diagnosis. The 2nd (a week later) his stomach and intestines were full of gas from not eating. He’s been on Entyce to stimulate his appetite, Reglan to help with motility and formerly prilosec but now pepsid, along with gasX as needed. He seems interested in food sometimes, but will eat a few bites or maybe a cup at a meal with lots of add-ins to entice along with constant encouragement (begin him to eat) and stop. Often, his lower abdomen (intestines) are very distended after eating just a small amount. I hate adding all the human food for him because his kibble is exactly what he needs according the clinical veterinary journal articles I could find for feeding a giant breed puppy to prevent rapid growth and joint issues and the calorie calculations I have done. However, if we don’t; he doesn’t eat, as we tried that 3 months ago only to have him refuse to eat for 5 days when we gave him just kibble with homemade bone broth. We have an appointment with Missouri university’s veterinary team a week from today to try to get answers, but are not hopeful that we will leave with an answer the same day. As a registered dietitian that works with humans, I believe he has IBS/IBD or Addison’s disease. Although after his free cortisol levels came back low, his follow-up ACTH stimulation test was supposedly normal to r/o Addisons. If he does just have IBD, is there a dog food that fits the need for a giant breed puppy that will help relieve symptoms? We also had plans to take him to a dermatologist in the area that is highly recommended by everyone we’ve talked to because he gets very itchy and red when he lays in the grass, but also hive-like bumps all over his body. This has been postponed due to these other priority problems we’ve encountered. Should we see the dermatologist before changing foods so we know if a hydrolyzed diet would help or is it okay to try it and see if symptoms improve? Obviously, we are hoping a vet can figure out what is wrong before trying to treat, but everyday is such a struggle that I spend literally all day trying to feed him his 3 meals-guessing which foods he will try/tolerate, having to switch multiple times during even the same meal. I cannot keep living like this and seeing him uncomfortable. I have looked for a board certified veterinary nutritionist, but there are none in the Kansas City area where I live that I have been able to find. Thanks! – Jamie

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