There are a number of genetic issues to consider when selecting a Rottweiler. Certain genetics will give us disqualifying issues such as long coats and significant health issues like life threatening heart conditions. It's our goal to avoid any and all issues we can to produce sound, healthy dogs.
Let's start with some big ones: eyes, heart, thyroid, hips, and elbows.
The biggest concern with eyes is cataracts leading to blindness. The OFA, CERF and ACVO each offer a screening process wherein an eye exam is submitted and evaluated. Since cataracts typically present before 2 years but can show up at any age it's a good idea to continuously monitor a dog's eyes with yearly check ups.
Cataracts are not always genetic or hereditary. That's the good news. The bad news is more often than not they are an indicator of other eye health issues and diseases. Retinal issues are also a common concern in the breed and vary greatly; since many can be genetic these issues should be avoided altogether in breeding stock when possible.
Heart issues can really run the gamut. They start from harmless murmurs and go clear to conditions and diseases affecting one or more chamber of the heart, how blood reaches or leaves the heart, and more. The Rottweiler Health Foundation has some good information as a starting place when researching potential heart issues in your future Rottweiler.
We'll start by discussing murmurs a little bit. A heart murmur can be nothing. The simplest way it has ever been described to me is an echo heard within the heartbeat on your dog. It could be a simple variation in the shape of one or more of the chambers in the heart. Murmurs are sometimes mistakenly detected because of breath sounds or even the position of your dog. Many murmurs heal on their own or remain for the life of your dog but never impact their health. That having been said - many are not so harmless so all murmurs in breeding stock should be thoroughly explored and diagnosed. A murmur can be the first indicator of another issue such as subaortic stenosis (SAS) and doctus arteriosus (PDA) which are both congenital.
The real concern with heart issues whether they are genetic or not, present in youth or adulthood, involve: the valves, the muscle that is the heart itself, or one of the chambers of the heart is blood flow - your dog needs his heart to move, breathe, think, etc. A bitch with a heart condition will not tolerate labor well. Any dog with heart concerns may be overstressed by the athletic work we often ask of them. And of course, heart issues can be life threatening. The OFA offers a cardiac clearance for congenital heart diseases that should be obtained by all dogs used for breeding.
Hypothyroidism is the big concern here. Such a condition can be genetic and should be screened against. This condition usually occurs at mid age but can show up at any time so frequent thyroid tests should be done. Once again, the OFA does offer a program as well. The most common form of hypothyroidism in dogs is autoimmune and as such the procedure is to check for the auto-antibodies that the dogs' own immune system is producing.
The risk with a thyroid issue varies greatly depending on diet, exercise, age, treatment including drug therapy, and your usage of the dog. For example, our spoiled lazy pets can quickly become very obese and experience further issues with their joints, heart, and digestive system. Thyroid problems can lead to fertility issues as well especially in bitches.
This is arguably the most important screening to obtain on breeding stock Rottweilers: hip dysplasia. Hip dysplasia, to put it simply, is the upper most bone of the leg being loose within and eventually detached from the hip socket. In many cases this is genetic but not all. Therefore, all dogs, even those from many generations of clear and healthy hips, should be screened for the condition.
Hip dysplasia is very painful for a dog and can lead to other more severe and painful conditions including various forms of arthritis. A variety of surgery and drug treatment options exist to help ease a dog's comfort and prolong his or her mobility but the best choice here is to avoid the issue from the beginning.
Elbow screening actually tells us the change in the elbow from what would be a normal position (given in Grades 1, 2 or 3). A perfectly positioned elbow would be a Normal. Based on any issue sighted with an OFA elbow screening done at 2 years of age we can further test to determine what condition is causing the elbow degeneration. There are at least 3 major conditions to consider from a genetic perspective (any of these 3 could be genetic) so elbow screening is a must on dogs used for breeding.
We consider a dog with only 1 elbow as a Grade 1 (with the other elbow Normal) acceptable for breeding because some slight wear in the joints is normal on any dog especially a large powerful breed. Example: Escobar has one Grade 1 Elbow from a screening done at 4 years of age. Elbow screening is done at 2 years of age traditionally. Only very slight change in an elbow of a 4 year old suggests healthy joints with mild degeneration. Most countries with restrictions on breeding dogs based on health screenings allow Grade 1 dogs to be used in breeding when those results are obtained at 2 years of age.
Elbow dysplasia posses risks to a dog's comfort and stability. Later in progression of this disease a dog many even require corrective surgery or have a great deal of trouble with mobility. Working closely with strong genetics and practising careful screening can significantly help reduce the occurrence of elbow diseases.