Therefore, the creation of specific breeds is relatively new in the grand scheme of the history of the domestic dog. Bones of truly domesticated dogs were found dating back to as early as 5,000 BC. Ancient pictures show dogs that were of definite sight hound type. (Dogs of Ancient Egypt, J. Dunn). Back to Hybrid Vigor: is it true? No. Returning to the cock-a-poo example. Poodles and Cocker Spaniels have many of the same health problems; therefore, a cross of them might actually stand a higher risk of inheriting a problem than a purebred pup from a good breeder. Some of the problems in both breeds are: hip dysplasia, progressive retinal atrophy, epilepsy, poor temperaments, allergies, skin and ear problem, Legg-Calve-Perthe's, luxating patellas, hypothyroidism, cryptorchidism, gastric torsion ( Cock-a-poos, Cindy Tittle Moore, 1997). Yes, things like ear infections, allergies, temperaments and gastric torsion have hereditary as well as environmental influences. Now, why did I state a cross might stand a higher risk of a hereditary problem than a dog from a good breeder? Rarely do people breeding crosses do any health tests – genetic or otherwise. They assume that an annual veterinarian visit and shots are all that is needed. Maybe for a pet dog, but breeders need to consider the genetic health of puppies produced. Things such as Hip and Elbow Dysplasia, Luxating Patellas, various eye problems, von Willebrand's (a bleeding disorder) and Thyroid function are common in many, many breeds and crosses. The myth that purebreds are unhealthy or nasty came about due to bad breeders who either did not care about health testing or who were ignorant and felt that dogs who show no outward signs of a problem do not have it. A purebred dog from a good and educated source has a greater chance of being healthier than a crossbred. |