PENNHIP VS OFA
PennHIP and OFA screening are the primary methods of assessing hip health for breeders. PennHIP screening measures joint laxity (known as the distractive index) as well as the conformation of the hip joint, but only gives a percentile index for joint laxity because evaluating hip conformation is somewhat subjective and so more difficult to score without bias. The higher the distractive index, the laxer the joint, and thus an increasing probability of developing degenerative joint disease known as hip dysplasia.
OFA evaluates hip conformation and looks for signs of hip dysplasia or arthritis and gives a grade based on 3 radiologists’ subjective interpretation. OFA films can be taken for a preliminary assessment after 1 year of age, but a permanent grade is not possible until they are at least 2 years of age. This ensures full hip development and is the fairest age to assess true hip conformation
Primarily, because if you really want to know what condition your dog's hips are in and their chance of getting dysplasia, then PennHIP it can tell you and you can do it early. PennHIP evaluation can be done as early as sixteen weeks of age, and even if you wait until six months, knowing early gives you many options that OFA cannot provide. A loose-hipped puppy at six months is a loose-hipped dog for life. If you already know this it can save you considerable time and expense in training and care.If you were planning on future breedings you know now that this is not the dog for you. You can decide to keep them as a pet and have them neutered to prevent passing on dysplastic genes, or you can find them a good non-breeding home.
On the other hand, the dog deemed tight-hipped that performs well early, might be on track for an extra litter or two of breeding, more than paying for the cost of the examination. Speaking of breeding, the PennHIP is much better for use in breeding than the OFA.
Research has shown that the heritability (the passing of a trait to offspring) is much higher for the distraction index (DI) that tells the laxity of a hip joint. In contrast, scoring of the two-year old dog by simply looking at joint conformation and the presence or absence of osteoarthritis (i.e. having an OFA done) has not shown to be predictably passed on. This is why there is no guarantee that if you breed OFA graded "excellent" dogs to each other that you'll get OFA graded "excellent" puppies. It is also why you can't take an OFA "excellent" dog, breed it to an OFA "fair" dog, and get OFA "good" (meaning a grading somewhere in between) puppies.
The heritability simply doesn't work that way. Again, on the other hand, the high heritability of the PennHIP does allow for choosing breeding pairs that can move the average DI through successive litters toward a better and better score. Of course, ideally you breed only dogs with very low DI measurements period. But sometimes that is not how the real world works. PennHIP allows you the ability to know which dogs need to be bred, which don't, and which ones will need help by only being bred to other very tight hipped (low DI) dogs.
Fowl Mouth Labradors does both PennHIP and OFA screenings on our dogs to ensure the best result we can guarantee. However, we strongly believe in the PennHIP foundation and it's beliefs and teaching in regards to the health and science behind any breed, not just the Labrador. With this in mind we ask that you decide to educate yourself in this aspect as well by clicking the discover more button below.