Every breed has a different set of potential problems for it. I have listed common ones below, but this is not to say that all dogs must be checked for everything listed. You need to do research in your breed to find out what the common problems are. You will also need to research the particular bloodlines you are using to see if they are prone to any additional problems you want to know about and screen for as well.

Eyes

Most breeds require eye checks of some sort, for a variety of problems. These include, but are not limited to problems such as

* Progressive Retinal Atrophy (PRA). This disease eventually causes total blindness. In some breeds the onset is quick, before the dog is two or three. In others, the onset is much later, when the dog is four to eight years old (and may have already been bred). Irish Setters have a test available that can detect carriers and affected dogs; other breeds do not have this recourse. It appears to be a simple autosonomal recessive, but the late onset complicates breeding programs. If a dog is affected, then both parents are either carriers or also affected.

* Retinal Dysplasia. Causes eventual blindness. This is believed to be hereditary. Some dogs can be detected with this condition in puppy hood, but carriers cannot be identified until they produce such puppies.

* Collie Eye Anomaly (CEA). This affects the collie breeds (bearded, border, rough, smooth) as well as some closely related ones. This condition also causes eventual blindness and is inherited.

* Cataracts. There are many forms and causes for cataracts, but some forms, such as juvenile cataracts, are inherited and such dogs should not be bred.

* Entropion, Ectropion: These are conditions in which the eyelids turn in or out, causing various problems and often pain for the dog.

The Canine Eye Registry Foundation (CERF) in the USA registers dogs that are found to be clear of eye problems by a board certified (AVCO) veterinarian. Dogs need to be cleared yearly as there are some types of eye problems that show up later in life.

Hip and joints

There are a variety of joint problems found in most breeds. Toy breeds can have joint problems too; just because your breed is smaller doesn't mean you can figure you are free of hip dysplasia and be done with it. There are several problems that specifically affect smaller dogs!

* Hip dysplasia is probably the best known problem. This is a malformation or deterioration of the hip joint, so that the socket it sits in is too shallow to secure the head of the femur. As the condition progresses, arthritic changes begin to destroy the protective cartilage and the dog may experience severe pain if the condition is bad enough. Some dogs are asymptomatic, but still should not be bred. This condition primarily affects the medium-to-large breeds, but smaller breeds have been known to be affected, for example Cocker Spaniels and Shetland Sheepdogs can have this problem. To make sure your dog is free of hip dysplasia, you need to have the hips radiographed and then obtain an expert analysis of the xrays. Your vet isn't necessarily the one to do this! In the US, you would mail the xrays to the Orthopedic Foundation of Animals and wait several weeks for their evaluation. In Canada, Europe and Britain, there are equivalent programs, but all differ in the type of certification and age at which they will certify; some organizations certify after one year of age, others certify after two years of age.

* Osteochondrosis Dessicans (OCD) is an elbow joint problem. A bone spur or a flake wears away at the joint which becomes stiff and painful. Xray evaluations of these joints are also needed. Many breeds that are prone to hip dysplasia may also have OCD.

* Patellar Luxation is a problem affecting the kneecaps. Smaller dogs are more prone to this problem than larger ones are. The kneecap will slide out of place and lock the leg straight. Diagnosis is fairly straightforward and surgery can correct the problem, but no dog with patellar luxation should be bred as this is also an hereditary condition.

There are a few other types of problems, affecting other joints like the hocks, or affecting the spine, that you should be aware of in some breeds. This is only an overview to give you an idea of what kinds of problems are out there. Remember that joint problems, even if not hereditary, may make it problematic for a bitch to be bred. Pregnancy is hard on the joints and on the body in general and if she isn't in the best of physical health, it is much kinder not to breed her.

Other things to check for

* In some breeds, deafness is a potential problem. Puppies at risk should be BAER tested and any that fail should be neutered.

* Heart conditions in many breeds must be checked for. Subaortic stenosis (SAS), other malformations of the heart or valves.

* Hemophilia type of problems, e.g., von Willebrand's disease and others.

* Malabsorptive syndromes, digestive problems.

* Epilepsy.

* Allergies.

* Incorrect temperament for breed.

Finally, remember that not only the potential dam but also the sire must be checked for all the things appropriate for their breed and particular bloodlines.