Definition - is the improved or increased function of any biological quality in a hybrid offspring or the increased vigour or general health, resistance to disease, and other superior qualities that are often manifested in hybrid organisms, especially plants and animals.
So essentially, hybrid vigour means that by crossing two unrelated animals to each other, you are decreasing the relatedness and therefore the overlap of genetic issues that are brought on by inbreeding and line breeding. How does this apply to Miniature Goldendoodles? Well, lets break this down.
Golden Retrievers struggle with the following diseases:
Dystrophic Epidermolysis Bullosa
Sensory Ataxic Neuropathy
Miniature Poodles struggle with the following diseases:
Hip Dysplasia (although not very common compared to Standard Poodles)
Von Willebrands Disease I
Von Willebrands Disease II
Neonatal Encephalopathy with Seizures
Okay, now that we have looked at the common diseases amongst the two parent breeds, we can take a look at the ones that over lap. So, Hip Dysplasia, Eye Disease, Heart Disease, Degenerative Myelopathy and PRA are all in common. This means that because they are common in both breeds, you will not get the beneficial effects of hybrid vigour with these diseases. Now, as for Elbow Dysplasia, Muscular Dystrophy, Degenerative Myelopathy, Ichthyosis, Patellar Luxation, Legge-Calve-Perthes, Dystrophic Epidermolysis Bullosa, Sensory Ataxic Neuropathy, Gangliosidosis, Osteochondrodysplasia and Von Willebrands Disease I and II, you will see the health benefits of this cross.
It is important to understand how most genetic diseases work. Most disorders are a result of a recessive gene. When you have dogs that are closely related, you are doubling up on genes too often and opening yourself up to more genetic disorders. This is one of the most common causes of disease among purebred dogs. It is important to breed ‘like’ to ‘like’ as, you want to breed for certain traits that you want exhibited in your breed, but in the process of breeding closely relates dogs together, we also having those recessive traits come to the surface more. This is why breeding Goldendoodles is considered healthier than the parent breeds because we have more genetic diversity in this cross and less doubling up of those genes that cause genetic issues.
All Goldendoodle breeders should be testing for the common diseases among both breeds to make sure there is no overlapping of genetic disorders, just as you would if you are breeding the purebred parent. Above this, the Goldendoodle breeder needs to once breeding past the F1 generation, test for all disorders that are common in both parent breeds, as you are then getting more overlap in generations, but are also breeding more to type.