Expert: Dr. Louis N. Gotthelf - 5/24/2005

Question
Hello Dr. Gotthelf ~
What makes one puppy develop allergies over another? Is there a predisposition or a behavioral response or personality factor? Or is it primarily genetics. I am a breeder of Jack Russell Terriers, and it seems as if one out of every 4 puppies born ends up with a skin allergy. The inflicted puppies are allergic to up to 28 things including environmental as well as food allergies. I hate to see them suffer and itch so much. One owner has started shots but no sign of relief yet (2 months). Am I being irresponsible to bring more of these inflicted puppies into the world. They live happy meaningful and seemingly high quality lives, but I feel very sad about this. Thanks for your help.  

Answer
Atopic dermatitis is mostly heredity. Many breeds are prone to atopy.  We think that there is a breed specificity to food allergies, too. However, with some food problems, it is not a true allergic reaction, but a skin reaction to a chemical in the food. If all of your pups are turning up atopic or food allergic, then there is some genatic problem in your lines.

There are other types of allergies that may develop based on the exposure to allergens.  Flea allergy is like that.  Many immunologists think that if a dog was continuously exposed to fleas for its life, it probably would never develop flea allergy.  But intermittent, or seasonal flea exposure makes these dogs and cats more likely to develop a reaction.  It is just like vaccines.  The "booster" vaccine is when the immunity is generated, not the initial puppy shots.  They just "sensitize" the immune system.

Allergies are complex and we really don't know very much about them.  

2 months of allergy shots is nothing.  It takes almost 9 months before the amount of allergen in the shots is enough to do anything.