Dear Daisy Dog
I hear people say that mutts are healthier than pure-bred dogs, but experience with my own dogs tells me that pure-breds are as healthy as mutts. What is the truth?
Both points of view have some validity.
When animals that share similar traits -– such as dogs of the same breed -– are mated, the traits are accentuated in their offspring.
A responsible breeder mates dogs whose family members share positive characteristics, like good health and sound temperament.
Such careful breeding strengthens these desirable traits in future generations, even when the dogs are inbred, i.e., bred to family members.
While many people think inbreeding weakens a breed, it can improve the breed if done right. One of the most inbred species, the laboratory mouse, is also one of the healthiest.
However, some people breed dogs with medical or behavioral problems, such as allergies, hip dysplasia or aggression, that can be genetically transmitted to their young.
When both parents carry the same harmful gene, their offspring inherit it, regardless of whether they are pure- or mixed-breed dogs.
For example, I know a Lab-shep mix with hip dysplasia. His parents had the same problem.
However, if only one parent carries the problem gene, the pups often are spared or develop only minimal problems.
This dilution of deleterious genes is termed “hybrid vigor” and accounts for the good health mixed breeds often have.
In short, inheriting the right genes helps both pure-bred and mixed-breed dogs enjoy long, healthy lives.