DISEASE BASED PHENOTYPIC EVALUATIONS
Updated: Jan 26, 2023
My last post on genetic testing was so popular I decided to do one on another type of health testing we do. While genetic testing is very useful, it is also limited. There are many things that can affect our dogs that there are no genetic tests for, and that's where screening tests come in. Screening tests help us by eliminating or making informed breeding decisions on any dog that is affected by or shows signs that can lead to the development of, an inheritable from our breeding program in order to reduce the chances of passing these conditions down to their offspring. These are not genetic tests so passing does not necessarily mean puppies will be free from these conditions, but by testing we are stacking the deck in their favor and all though they are not definitive, they have greatly improved the health of many breeds. They are also an excellent way to prove your dog is in great health and can handle a breeding.
Hip Evaluation (CHIC Requirement- One time)
There are two options when doing hip evaluations. OFA radiographs and PennHip. PennHip can be done after 1 year and is a bit more in depth. However, it is also much more expensive with way lower availability. Official OFA radiographs (as pictured above) can only be done after 2 years. Both look at the hip joint for any signs of Hip Dysplasia. Technically they can be done at any vet, but most vets do not know how to do proper positioning and if the positioning is bad OFA will not accept the radiograph and it will need to be redone. Bad positioning can also make a dog appear to be dysplasic when they are not, so I always recommend going to a vet that is familiar with the process and have done OFA evaluations before.
When submitted to OFA, the dog's radiographs are examined at 9 different points by 3 random board-certified veterinary radiologists and given a rating based on all 3 radiologist's scores. They can be graded as: Excellent, Good, Fair, Borderline, Mild, Moderate, or Severe.
In my opinion the extra money for a Pennhip evaluation here isn't worth it. Excellent or good hips wont suddenly look bad with Pennhip, but it is more in depth so it could be worth doing if you can find a good deal on it or if you have a dog that comes back as fair or borderline before removing them from your program.
Elbow Evaluation (One time)
I always evaluate for Elbow Dysplasia at the same time as hips. The elbow evaluation is similar to the hip evaluation except the only option is the OFA radiograph and the elbows are graded as either normal, or dysplasic grade 1-3
Cardiac Evaluation (CHIC Requirement- One time)
OFA cardiac examinations can only be performed by a board-certified cardiologist after the dog is 1. In our breed both auscultation and echocardiograms are accepted, but an echo is much more in depth and is my preferred testing method even though it is much more expensive. Auscultation involves a cardiologist listening to various areas of the dog's heart with a stethoscope for an extended period to identify any abnormal sounds. With an echocardiogram, a cardiologist uses a doppler to look for any abnormalities. Cardiac exams are graded as normal, or abnormal: grade 1-6
The reason I prefer the echo is many dogs can pass an auscultation that would fail an echo.
Eye Evaluation (CHIC Requirement- Yearly)
Much like many of the other evaluations, an OFA eye evaluation can only be done by a board-certified specialist in that field. In this case, a board-certified ophthalmologist. The ophthalmologist will do a thorough examination on both eyes and report any abnormalities up to a single misplaced eyelash. There are many things they are looking for, some of which will not give you a failing result. These are what are called breeder options. Breeder options are things that may or may not be inheritable but does not represent potential compromise of vision or other ocular function. So, you can have a clear, which means nothing was found, a clear with breeder option, or they can find a disease that would prevent a clear. These are to be repeated yearly for the life of the dog to meet CHIC requirements.
I am separating these tests because I do not yet do them and do not know much about them, but I am interested in learning more and adding them to my testing in the future.
Patellar Luxation
I have heard this is starting to show up in our breed, so I am interested in learning more about it and testing for it in the future.
Thyroid
This I need to learn more about the difference in the OFA test vs a vet test because my dogs already get their tyroid tested as part of their yearly early detection panel with my vet. If it proves to be a more in depth/definitive test I will be adding this to their testing, if not there is no reason because they are already getting it tested yearly anyway.