What causes a dog to not absorb nutrients?

Bacterial overgrowth is a condition of the small intestine resulting in increased numbers of bowel bacteria. The major concern with bacterial overgrowth is the development of a condition called small intestinal bacterial overgrowth (SIBO).

The bacteria cause damage to the absorptive surface of the bowel so digested food cannot be absorbed through the bowel and into the body, resulting in malabsorption of nutrients.

Is this the same as an infection causing enteritis?

Malabsorption and SIBO both result in diarrhea, similar to that associated with enteritis. However, with bacterial overgrowth the diarrhea is chronic in nature, often lasting weeks or months.

Are some dogs more susceptible than others?

German Shepherds appear to have a higher incidence of malabsorption problems. These problems are frequently associated with exocrine pancreatic insufficiency (EPI) but SIBO can occur either with or without EPI. See handout “Exocrine Pancreatic Insufficiency in Dogs” for more information about this condition.

What are the common clinical signs of malabsorption?

The principal sign is weight loss with chronic diarrhea. Most dogs will have a normal or increased appetite but continue to lose weight.

Can it be differentiated from pancreatic insufficiency based on the symptoms?

Specific blood and fecal tests are necessary to differentiate EPI and SIBO. Dogs with malabsorption often do not have as voracious an appetite and the diarrhea is usually not as voluminous as EPI.

What is the cause of this condition?

Many cases are idiopathic (unknown cause). SIBO is frequently associated with exocrine pancreatic insufficiency (EPI).

Can the condition be cured?

Many cases respond to long term antibiotics. Tylosin (Tylan®), oxytetracycline and metronidazole (Flagyl®) are common antibiotic choices that are usually combined with special diets to treat this condition. In cases of primary SIBO without any complicating factors, the prognosis is usually good.

Is your dog not feeling so well? Could he be suffering from one of the many digestive problems in dogs? If he's vomiting or you notice problems with his stools, he may be suffering from issues with his gastrointestinal or digestive system.

Gastrointestinal problems in dogs happen for a variety of reasons, and any one of them may cause your dog to not feel well. Did he eat something new? If he ingested something other than dog food, he may be allergic, intolerant, unable to digest it, or even worse, it could have given him an infection. Also, some breeds, such as German shepherds, Great Danes, and Schnauzers, are more prone to digestive issues.

Here are seven digestive problems in dogs you should be aware of. It is important to learn about what could make your dog sick, so you can prevent it. Also, if gastrointestinal problems in dogs are already plaguing your pet, you'll learn what you can do to help.

1. Diarrhea

You may notice that your dog is having loose, liquid stools. Diarrhea is a common ailment for dogs and other animals and is caused by many different things. Here's a list of a few different reasons diarrhea occurs:

• stress
• spoiled/rotten food
• allergies to specific ingredients in foods
• changing dog foods too quickly
• internal parasites
• infections
• failing organs

2. Small intestinal malabsorption

Malabsorption is a type of digestive problem in dogs. If your dog is experiencing small intestine malabsorption, it means he either isn't digesting his food, or he isn't absorbing the vitamins and minerals after digestion.

3. Colitis

Colitis, an inflammation of the membrane lining of the colon, is among the common digestive problems in dogs. It also inflames the large intestine, so your dog may experience painful stools or diarrhea. The inflammation and irritation can be either chronic or acute.

Whipworms can be the cause for colitis. Also, if your dog is suffering from tumors or polyps, they may also irritate the colon, causing colitis. A change in food, ingesting something other than food, or an allergy to a specific food is often the culprit for a colitis attack.

4. Acute gastroenteritis

Usually a temporary issue, acute gastroenteritis causes inflammation in the stomach or intestines. It usually occurs when a dog eats high-fat or spoiled food. It can also occur if a dog eats anything poisonous or something he is allergic to. Internal parasites can be a harbinger to gastroenteritis. Stress is another trigger.

5. Hemorrhagic gastroenteritis

Similar to acute gastroenteritis, hemorrhagic gastroenteritis is usually a temporary issue, but it can be fatal if untreated. Hemorrhagic gastroenteritis causes severe vomiting and bloody stools, usually in diarrhea. It can be brought on by ingestion of foods or substances that your dog shouldn't be eating or is allergic to, as well as pancreatitis and other autoimmune illnesses.

6. Pancreatitis

Pancreatitis is an infection or inflammation of the pancreas. The reasons why pancreatitis occurs are unknown, though high-fat food may be to blame. Other issues that may cause the condition include trauma to the pancreas, infections, or a disease.

7. Exocrine pancreatic insufficiency

Exocrine pancreatic insufficiency occurs when your dog's pancreas fails to produce enough digestive enzymes. Weight loss, an increase in appetite, and large, soft stools are the major symptoms. If you've noticed an extreme weight loss in your dog, he may not be producing enough enzymes in his pancreas.

How can you help?

Know your dog's baseline

Digestive problems in dogs can appear suddenly, so always be on the lookout for ways to protect your pet. The best way you can take care of your dog is knowing what his normal behavior and health looks like. How many times a day does your dog normally defecate? What do his stools generally look like? While gross to think about, and even more so to monitor, it can be a very vital piece in maintaining your dog's health. Talk to your vet more about what a dog's stool should look like when healthy to better understand what to look for if you notice abnormalities in your dog's behavior. Does he ever throw up? While vomiting doesn't always scream a larger digestive issue, it is one of the more common signs that something is wrong. If you notice this happening frequently, it is a good time to get your pup to the vet to have him checked out. How much does he eat and drink? These are all questions you need to know the answer to, so that you can identify when something is wrong.

Monitor what your dog eats at all times

Make sure your dog receives well-balanced nutrition and doesn't come in contact with any food he shouldn't be eating. At the same time, don't let your dog swallow anything he isn't supposed to, even if it's not food. Certain plants or foreign objects will make your dog extremely ill.

Healthy and easily digestible dog food will go a long way for an anxious dog's belly. Also, regular preventative trips to the veterinarian will keep you on top of any health issues your dog may be facing.

Keep your dog hydrated

A dog suffering from a gastrointestinal or digestive issue needs to stay hydrated, especially if he is vomiting or has diarrhea. One thing to keep in mind: If you notice that your dog begins drinking less frequently and less water or he is lapping it up in an extreme amount, it's a sign that something is amiss. Being well-hydrated is a key to keeping your dog healthy.

Be supportive and calming

Gastrointestinal problems in dogs can be upsetting for the entire family. Your once happy, playful dog is suddenly lethargic, withdrawn, and possibly vomiting or ill with diarrhea. Because stress can cause digestive problems, try to keep your dog calm and well-adjusted. In times of high stress, you may notice your dog having more stomach issues. Find coping mechanisms that work for your dog, such as petting him or scratching his belly.

Contact your veterinarian

If you even suspect that your dog is suffering from a digestive or gastrointestinal issue, contact your vet immediately. Many of these conditions are serious, and your dog will need to be monitored closely, and possibly be treated with medications.

In the case that your dog is suffering at night or on the weekend, don't wait until the vet office is open. Consider visiting an urgent care facility.

Erin Ollila

Erin Ollila is a pet enthusiast who believes in the power of words and how a message can inform–and even transform–its intended audience. Her writing can be found all over the internet and in print. Reach out to her on Twitter @ReinventingErin or learn more about her at http://erinollila.com.

Effective treatment of EPI and small-intestinal disease depends on the nature of the disorder, but therapy may be empirical when a specific diagnosis hasn't been made.

Treatment will require lifelong supplementation of each meal with pancreatic extract. Powdered extracts (1 tsp/10 kg body wt) are preferable to tablets, capsules, and most enteric-coated preparations. Fresh or fresh-frozen pancreas can be used as an alternative (100 g/meal for an adult German Shepherd). Treatment of EPI in cats is similar, but cobalamin supplementation is almost invariably required.

The response to pancreatic enzyme replacement therapy may be poor and adjunctive treatments may be necessary:

• Secondary SIBO may be suspected, and the animal should be treated concurrently with oral antibiotics for ≥1 month (see below).

• Acid suppressants (eg, H2-receptor blockers such as cimetidine or ranitidine; proton pump inhibitors, such as omeprazole) may be given 20 minutes before a meal to inhibit acid secretion and minimize acid degradation of enzymes in the pancreatic extract, but they are expensive and their value is questionable.

• Oral multivitamin supplementation should be considered as supportive therapy, but cobalamin (500–1,000 mcg/week until normalized) should be given.

Dysbiosis and antibiotic-responsive diarrhea. In dogs with ARD, a low-fat diet may help by minimizing secretory diarrhea due to bacterial metabolism of fatty acids and bile salts. Oral broad-spectrum antibiotic therapy with oxytetracycline (10–20 mg/kg, three times daily for 28 days) has been successful. Metronidazole (10–20 mg/kg, twice daily) and tylosin (20 mg/kg, three times daily) are effective alternatives; there is rarely a need to use other antibiotics, and the nontargeted use of fluoroquinolones should be avoided.

Repeated or longterm treatment may be necessary in dogs with idiopathic ARD. Vitamin supplementation may be helpful, particularly for animals with cobalamin deficiency. Secondary ARD usually resolves with appropriate management of the underlying disease (eg, EPI), but idiopathic ARD can be difficult to control, especially in young German Shepherds, which are predisposed to developing the condition.

Inflammatory bowel disease. Treatment of idiopathic inflammatory bowel disease should initially attempt to eliminate or control an underlying antigenic stimulus that may be playing a primary or secondary role in the damage. Treatment should first involve the use of a protein hydrolysate diet. If this is refused by a patient, the diet should comprise digestible carbohydrate (preferably rice, which is most digestible) and a high-quality single protein. Restriction of fat content may also be valuable and can minimize the secretory diarrhea that is a consequence of bacterial metabolism of fatty acids and bile salts. Oral prednisone/prednisolone (1 mg/kg, twice daily for 2–4 weeks, followed by a reducing dose) is indicated in cases of intestinal disease with an obvious inflammatory component, such as lymphocytic-plasmacytic enteritis and eosinophilic enteritis, and no evident underlying cause. In more severe cases, it may be necessary to add chlorambucil (2–6 mg/m2/day, PO, until remission, followed by drug tapering) in cats and dogs or ciclosporin (5 mg/kg/day) or azathioprine (2–2.5 mg/kg/day) in dogs.

Cats are often given adjunctive metronidazole (10 mg/kg, twice daily); the beneficial effect of metronidazole may be a result of an inhibition of cell-mediated immune responses as well as anaerobic antibacterial activity. However, the value of metronidazole in combination with prednisolone in the treatment of IBD in dogs has not been shown.

Lymphangiectasia. In lymphangiectasia, a severely fat-restricted, calorie-dense, highly digestible diet that reduces diarrhea has been recommended but tends to exacerbate weight loss. Supplementation with fat-soluble vitamins is advised, and additional medium-chain triglycerides have been recommended as an easily absorbable fat source that bypasses the lymphatics, although this mechanism is now doubted. Prednisone/prednisolone therapy may be beneficial for its anti-inflammatory and immunosuppressive effects, especially if there is associated lipogranulomatous lymphangitis. The response to treatment is variable; clinical signs may sometimes abate for months or even years, but the longterm prognosis is grave.

Infectious causes. Giardiasis can be treated with metronidazole or fenbendazole, and histoplasmosis treated with itraconazole (cats) or ketoconazole (dogs), with or without amphotericin B.

Intestinal neoplasia. The treatment of alimentary lymphoma involves an appropriate chemotherapy regimen, but response is very poor in dogs and poor in cats with lymphoblastic forms. In cats, treatment of small-cell villous lymphoma with oral prednisone and chlorambucil has been associated with prolonged remission.

Solid tumors of the small intestine (eg, adenocarcinoma) more typically produce signs of intestinal obstruction and bleeding with diarrhea rather than malabsorption. They are managed primarily by surgical resection.