By Rachele Baker, DVM – Question: Ali writes: I have a four-year-old neutered male lab. Recently I was told by my vet to feed him a hypoallergenic pet food as his ears are quite hot. He doesn’t appear to have ear mites or an ear infection. He is full of bounce and vigour as normal. He scratches and rubs his ears occasionally, but not in a way which is excessive or distressing to him. His ears don’t even look red, but they do feel extremely hot inside. He is otherwise healthy and as full of life and energy as always!
I have noticed that he seems to be licking his paws a lot too. His paws look fine. Maybe he is just cleaning the moisture or dirt off them.
I suppose my question is, can diet cause his ears to be hot? Will a hypoallergenic diet fix it? I was surprised when the vet suggested the hypoallergenic diet. I expected some kind of drops or something.
Answer: Hi Ali. Thank you for sending in your question as well as a photo of your dog, Indi. He is very cute.
The heat in Indi’s ears could be produced by low grade inflammation. Indi is showing classic signs of being an allergic dog since he is scratching and rubbing his ears and licking his paws a lot. He is likely scratching, rubbing, and licking because he is itchy. Dogs can be allergic to many things including food (adverse food reactions), fleas (flea allergy dermatitis – FAD), things floating in the air such as pollen, molds, and dust mites (atopy), or anything that touches their skin such as shampoos, carpet powders, and lawn chemicals (contact allergy). Dogs that have allergies to one thing often have allergies to other things as well. In other words, Indi may have food allergies and/or allergies to other things.
Food allergies tend to be non-seasonal (all year long) as opposed to allergies to airborne allergens (atopy) which are usually worse in the summer months. If Indi is scratching and rubbing his ears and licking his paws all year long but it seems to get worse in the summer, then he may have food allergies and atopy.
Food allergies (adverse food reactions) can develop in dogs at any age. Food allergies take time to develop and usually develop to foods that a dog has been fed for some time. The most common clinical sign of food allergy in dogs is non-seasonal itchiness. Food allergies in dogs can cause itchiness in many different areas of their bodies including their paws, ears, ventral abdomen (stomach region), axillae (armpits), groin, muzzle, eyes, and rectum. Dogs with food allergies may also have recurrent ear and/or skin infections.
Your veterinarian recommended a diet trial to see if the hypoallergenic diet will relieve Indi’s itchiness. A diet trial is considered the gold standard method of diagnosing food allergies in dogs. Blood tests for food allergies are not considered accurate for the diagnosis of food allergies in dogs. If a dog’s clinical signs improve while on the diet trial, this is indicative that they have food allergies. A diet trial is both diagnostic for food allergies and potentially therapeutic.
Diet trials can be performed with either a hypoallergenic diet or a novel protein diet. Hypoallergenic diets contain protein sources that have been broken down (hydrolyzed) into smaller molecules that are much less likely to produce an immune reaction than larger intact protein molecules. Novel protein diets contain a protein source that the dog has never eaten before. Food allergies take time to develop so the dog must have eaten a certain protein (such as beef or chicken) in the past in order to have developed an allergy to that protein. In selecting a novel protein diet, it is important to thoroughly document the foods that the dog may have eaten in the past including table scraps, treats, and flavored medications and supplements.
Dogs that have food allergies may be allergic to more than one food. In European and American dogs, beef allergy is the most common food allergy. The most common foods that cause allergies in dogs are beef, dairy products, chicken, eggs, and wheat. Feeding even a very small amount of a food that a dog is allergic to can cause a flare-up of clinical signs. In a study of dogs that were allergic to corn, the amount of corn in one single corn chip triggered a flare-up of clinical signs.
It is recommended that diet trials be continued for 6-12 weeks. During that time, it is important that you only feed Indi the hypoallergenic diet and absolutely nothing else including table scraps, rawhides, pig ears, cow hooves, flavored medications (including heartworm preventatives) or supplements, fish oils, dog biscuits or treats, flavored toothpastes, or flavored plastic toys. If he is receiving a chewable heartworm preventative, ask your veterinarian for a pill form of heartworm preventative. Any pills that you need to give him can be hidden in a small meatball of the canned hypoallergenic diet. It is important that dogs on diet trials not be allowed to roam so that they do not have the opportunity to get into food or garbage or get treats from the neighbors. It may also be necessary to keep Indi out of the room during meal times so that he does not get any foods that may have been dropped or spilled from the table.
If you want to give Indi treats during his diet trial, you can make dog cookies from the canned hypoallergenic diet recommended by your veterinarian. I have included a recipe for Dog Cookies From Canned Dog Food at the end of this post.
So if Indi has food allergies and you make sure to strictly adhere to the diet trial for six to twelve weeks, he should show improvement in his clinical signs. In other words, his ears should cool down, he should scratch and rub his ears less frequently, and he should discontinue excessive licking of his paws. However, as I mentioned above, he may also have allergies to other things so the hypoallergenic diet alone may not completely resolve his itchiness. Make sure you schedule follow-up visits with your veterinarian and discuss these things together.
Dog Cookies From Canned Dog Food
Ingredients: Canned dog food (~78% moisture content)
Open a can of dog food on the top and bottom. If you can’t open the bottom of the can with a can opener, just pop a hole in the bottom to allow air to enter. Then shake the can to slide the tube-shaped food out in one piece. Gently slice the canned food into one-half inch slices with a steak knife or other sharp knife. Then cut each slice into quarters.
Spray a baking pan with non-stick cooking spray and arrange the quarters of canned food in the pan. There is no need to space the cookies far apart because they will not spread out during baking but instead will shrink a little. Bake at 200 degrees Fahrenheit (93 degrees Celsius) for two hours and then gently turn the cookies over. Continue baking the cookies for about one and a half hours more or until the cookies are hard. Cooking times may vary. Check the cookies often while baking.
When the cookies are done, turn off the oven and leave the cookies in the oven for one and a half hours or until the oven has cooled. Then remove the cookies from the oven and allow them to thoroughly cool for thirty minutes or more before placing them in a zip-loc bag for storage. Cookies will be crisp on the outside and a little soft on the inside. Store in the refrigerator.
The Official Taste Tester in my Dog Cookies Test Kitchen, my golden retriever Savanna, gives these cookies two paws way up – she loves them!