Food allergies, intolerance different animals for pets

Dr. Robert Esplin and his Portuguese water dog Tressie. Enlarge

Q.: Dr. Bob, this seems like a silly question, but are food allergies and food intolerance the same thing? Amanda

A.: In one quick word no they are not the same thing Amanda.

Dogs, cats and people can have lactose intolerance but not be considered allergic to milk. In this case, the milk sugar, lactose, is not properly digested and causes the affected person or animal to develop diarrhea. Allergies are triggered by exposure to an offending protein.

Many pet foods use milk product as a low cost source of protein. Pets that have lactose intolerance will have soft stools to diarrhea. Puppies and kittens with diarrhea early in life should not be fed milk or foods containing milk product. Even milk intolerant pets can, in most cases, be fed cottage cheese or yogurt. That is because in the process of making these products the milk sugar is used up.

Lactose-free milk is sold and makes lactose intolerance a moot concern. Any animal can be intolerant of any food. Chronic vomiting following a meal is also a potential sign of food intolerance.

Food allergies are a problem of a different order.

The allergic reaction is usually systemic, with a variety of presenting signs. The most commonly known human food allergy is peanut allergy. It is so widespread that airlines do not give away peanut packages any more. Schools have gone so far to outlaw peanut butter sandwiches in lunch bags and cafeterias. In an affected human, peanut allergy is a potential medical emergency. Pets rarely show signs of peanut allergy.

In dogs and cats, food allergies usually cause skin signs, with itching being by far the most common. The common mantra about food allergies is ears and rears. That is, these are the most commonly affected areas of the food allergic pet.

Food allergies are not extremely common in pets. Between 10-15% of allergic dogs are affected by food allergies. Most allergies in dogs are associated with environmental allergens, such as pollen and mold.

There is no accurate and reliable test that can be run to find out if a pet is food allergic.

Some companies claim to be able to test for food allergy, but no dermatology specialist accepts these results as being reliable. The only method of finding out whether a pet has food allergy is to do an elimination food trial. There is no store food that can be used to be sure an accurate food trial has been completed. A food trial uses a unique, never before consumed, protein source and a unique carbohydrate source for at least 12 weeks. No other food source of any type can be given during this trial.

Houses with young children and multiple pets make a food trial very difficult.

Having said that no store food is reliable for a feeding trial, I can say we have had some success putting dogs with recurrent ear infections on ProPlan skin and intestinal diet with some success. Many high quality food companies with veterinary branded foods make hypoallergenic diets that are used to diagnose and treat food allergic dogs.

Before the effort to determine and eliminate food allergies, a serious effort to eliminate environmental allergies is critical. A trial treatment with cortisone to determine response is a realistic way of helping make the diagnosis.

Dr. Robert Esplin, a 1970 graduate of Ohio State University College of Veterinary Medicine, owns SylvaniaVET hospital at 4801 N Holland-Sylvania Rd. He writes a periodic column for ourtownsylvania.com and accepts all pet-related questions for it through email at drbob@sylvaniavet.com.