What Is Hydrolyzed Protein Dog Food?

Jennifer Coates, DVM
Written by:
Published: August 27, 2018
What Is Hydrolyzed Protein Dog Food?

Image via David Porras/Shutterstock

Veterinary prescription dog food is used to manage a variety of health conditions in dogs, but the concept behind it is not always clear. If your veterinarian has recommended a hydrolyzed protein dog food (or someone else has mentioned that one might be appropriate), you are probably wondering exactly what “hydrolyzed” means.

What Is Hydrolyzed Protein Dog Food?

Protein is a vital component to any diet. Your dog’s muscles, hormones and disease-fighting antibodies are all proteins. To make what their bodies need, dogs take proteins from food, break them down into building blocks called amino acids, and combine those amino acids into new proteins.

In some animals, dietary proteins can trigger an abnormal immune response. Hydrolysis uses water to chemically break proteins into pieces that are so small that the immune system no longer reacts to them. Veterinarians typically prescribe hydrolyzed protein dog foods to treat two diseases: food allergy and inflammatory bowel disease.

Dog Food Allergies

A dog’s gastrointestinal tract serves as a gatekeeper. It allows nutrients in while fighting off disease-causing microorganisms and keeping out anything else that is potentially harmful. But sometimes the body gets confused. Dog food allergies develop when the gut incorrectly starts identifying benign dietary proteins as a potential health risk and mounts an immune response against them.

Food-allergic dogs can develop a variety of symptoms, including:

  • Itchiness, which many involve the whole body or be limited to the feet, ears and/or face
  • Hair loss
  • Skin lesions
  • Recurrent skin or ear infections

Some dogs will also have digestive problems like vomiting, diarrhea and/or excessive gassiness.

Food allergy symptoms often begin when dogs are young (less than a year of age) but can become evident at any age. Dog food allergies may develop soon after starting a new dog food or after years of eating the same diet. Food allergies are diagnosed in all types of dogs, but Labrador Retrievers, Cocker Spaniels, Golden Retrievers, German Shepherds, Shar-Peis and Poodles appear to be genetically predisposed.

To diagnose dog food allergies, veterinarians typically recommend a food trial (usually lasting at least two months), during which dogs must eat only a hydrolyzed protein dog food or a diet made from a single-protein source that they have never been exposed to before. If the dog’s symptoms improve over this time and then reappear when he is fed his old food, a dog food allergy diagnosis can be made.

Inflammatory Bowel Disease

The line between food allergies and inflammatory bowel disease (IBD) is sometimes blurry. It is thought that, in some cases, food allergies can develop as a result of IBD or vice versa.

In any case, dogs with IBD have abnormal inflammation of their gastrointestinal tract. The inflammation may be widespread or localized, severe or mild, and these characteristics can change over time. This explains why dogs with IBD can have different symptoms that vary in their intensities. Signs of IBD can include:

  • Vomiting
  • Diarrhea
  • Weight loss
  • Increased or decreased appetite
  • Lethargy
  • Noisy gut sounds
  • Increased gas production

Inflammatory bowel disease can develop at any age, but it is usually diagnosed in middle-aged to older dogs. Some breeds, including Boxers and German Shepherds, appear to be at a higher genetic risk for IBD. Inflammatory bowel disease can only be definitively diagnosed with a biopsy of affected tissues.

Hydrolyzed Protein Dog Food Recommendations

Treatment for dog food allergies and inflammatory bowel disease centers on finding a diet that does not trigger symptoms in that patient. Immunosuppressive medications and other treatments may also be necessary in severe cases of IBD. Once a dog has been diagnosed, he will likely need to eat a special diet for the rest of his life.

Veterinary prescription hydrolyzed protein dog foods are an excellent choice for both food allergies and IBD. These diets are manufactured under the strictest quality control measures, which ensures that they aren’t contaminated by ingredients that are not included in the label. Eating prohibited foods is a major reason that diagnostic food trials and treatment for food allergies and IBD fail.

Hill’s dog foods that are hydrolyzed include Hill's Prescription Diet z/d Original Skin/Food Sensitivities dry dog food and Hill's Prescription Diet z/d Original Skin/Food Sensitivities canned dog food, both of which contain high levels of essential fatty acids to promote skin health.

Royal Canin Veterinary Diets come in several hydrolyzed varieties, including Royal Canin Veterinary Diet Hydrolyzed Protein Adult PS dry dog food, Royal Canin Veterinary Diet Hydrolyzed Protein Adult HP canned dog food, Royal Canin Veterinary Diet Hydrolyzed Protein Adult HP dry dog food, which can be fed to puppies, and Royal Canin Veterinary Diet Ultamino dry dog food, with proteins that have been broken down into the smallest pieces available in a dog food.

Purina Pro Plan Veterinary Diets come in a hydrolyzed soy formula, Purina Pro Plan Veterinary Diets HA hydrolyzed vegetarian formula dry dog food, and one based on hydrolyzed chicken, Purina Pro Plan Veterinary Diets HA hydrolyzed chicken flavor dry dog food.

Your veterinarian can help you find a dog food for allergies or inflammatory bowel disease that will keep your dog’s symptoms under control while still providing the balanced nutrition that is essential to good health.

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