Dogs can have similar problems as humans have, with allergies to some
types of food. It's possible that it could be an intolerance to
specific ingredients such as wheat or corn, or a general complaint
which is provoked my many types of food, such as colitis.
A dog experiencing dog food allergies may exhibit any of the following:
Vomiting bile or blood, poor appetite, diarrhea and blood in the
stools, itching, dry coat and skin, chronic or recurrent ear
infections, hair loss, excessive scratching, hot spots, skin
infections, increased bowel movements and any other abnormal behavior.
Should you suspect that your dog is allergic to a certain food, you
need to do some testing to make sure that it is indeed food which is
causing the problem, as other medical complaints can also cause similar
symptoms, like parasites, skin infections or any other.
It may mean that you avoid all commercial brands and stick to a
homemade style dog food recipe of protein and carbohydrate, of which
you can control exactly what goes into it.
The matter is further complicated because there are many additives in
dog food, and it may be one of these which is causing the allergy
rather than a certain kind of meat or grain.
Dairy products, wheat, chicken, chicken eggs, soy, corn, and beef are
the common culprits found in a dog's diet that cause allergies. "But
aren't these the most common ingredients in dog food?", you might ask.
Yes, and there is a reason for that. Just like people who cannot
tolerate lactose, being overexposed to these ingredients could be the
root of the problem.
An intolerance has not been built against lamb or rice, so many of the
pet foods now are including these in their recipe varieties.
These can really not be the solution to treat an intolerance
nevertheless, as much of these trade names contains soybean, egg etc.,
so verify the ingredients.
There are many hypoallergenic dog foods on the market to address the
increasing numbers of dogs with allergies. As with any comparison, dog
food recipes may or may not be suitable or palatable for your
individual pet, so these are just general guidelines.
One thing to consider is that many "healthy" dog foods may still cause
allergies in your dog if they contain that trigger ingredient, and even
human grade dog food might still be causing your dog stomach problems,
so be prepared to compare dog food brands extensively.
Like with people, an intolerance to wheat or dairy contained in dog
food, regardless of quality, can cause the end result. Another signal
that your dog may have an allergy is bad reaction on the skin.