Q. I have been told that mixed breed dogs are healthier than purebred dogs. Is that true?
A.
There is a genetic term called heterosis, also known as hybrid vigor or outbreeding. Heterosis enhances the improved health, fertility, and overall vigor observed in offspring (F1 generation) by breeding two unrelated dog breeds. This happens when the genetics between the parents are very different. With a larger gene pool, mixed-breed dogs are less likely to have recessive genetic disorders than purebred dogs. These disorders occur when an offspring inherits recessive genes from both parents for a particular disease. The puppies from outbreeding can still be carriers for these disorders, creating a potential increase in the next generation developing inherited diseases. For example, if two dogs bred carry genes for deafness, the puppies are at higher risk of being deaf.
The question, are mixed breed dogs healthier than purebred dogs, has not been answered. We see that genetic disorders may be less prevalent in mixed breed dogs, but health is bigger than just their genetic makeup. A new study addresses this question. Researchers surveyed 27,000 dogs’ health records for reasons resulting in veterinary visits. They wanted to see if the overall health of mixed breed dogs was better than purebred dogs. One conclusion of this retrospective is that dog breed is only one aspect of pet health.
The most common reasons for vet visits for all companions has nothing to do with breed. Pet insurance companies found the top reasons for vet visits are dermatitis, including allergies, parasites, and infections, ear infections caused by allergies, bacterial and fungal infections, followed by gastroenteritis with symptoms of nausea, vomiting, diarrhea, gas, and inappetence. Other common reasons for seeing the veterinarian are osteoarthritis, trauma, dental disease, urinary tract disease, liver disease, respiratory disease, and heart disease.
Many of these diseases are related to lifestyle, environment, and diet choices. When selecting your companion, do your research. Whether you are adopting from a rescue, shelter, or a breeder, you need to be sure of what you are looking for in a companion. The time you have to groom, train, play, exercise Fido, and financial means to care for your best friend is just as important as genetic considerations. Know the environment, lifestyle, social interactions, and physical activity that are available to the dog. Be proactive in planning both for preventative and medical care as he ages. Talk to your veterinarian about what your new pup may be prone to based on breed, size, sex, and so on.
By doing your research on breed characteristics and cross-bred information, you can prevent or reduce the common pit falls when adopting. You will be better prepared to enjoy and grow with your new companion.
Judith K. Herman, DVM, CVH
Animal Wellness Center
Augusta, Maine
www.mainehomeopahticvet.com