Fortunately, the Sheltie suffers from very few hereditary diseases. However, there are a few that must be considered and where possible checked out before you make your purchase. The main problem area is in the eyes. Collie Eye Anomaly was at one time very common, but with careful breeding over the later years, the incidence of the disease has been greatly reduced. Collie Eye Anomaly is present from birth and can be detected by a vet. The eyes may be small and deeply set. Visual loss occurs in less than one percent of affected dogs.
Of late there is a problem that seems to be showing much more frequently in the breed and that is pancreatitis. Fortunately, this can be prevented by a good diet. Should your Sheltie develop this disease it can be life threatening if action is not taken very quickly. There is an excellent article on the subject which was sent to me by a very caring owner who did not want other people to have to go through the problems that she experienced. It can be seen at:-
Hip dysplasia is fortunately very rare in Shelties, due mainly to the lightness of the breed. However, hypothyroidism (under active thyroid), is being seen more in Shelties. The symptoms are - loss of hair, inactivity and weight gain. The disease can be treated by medication, although it may take a while to achieve the correct dosage of drugs.
Collie nose is another disease which affects Shelties and is present from birth. It is an abnormal reaction to sunlight and shows as dermatitis or eczema, primarily affecting the nose, eye and adjacent areas. The disease is very slow to progress and at first might only show up as a slight reddening of the muzzle skin.
Dogs of (any breed) do not suffer from the common cold, but are subject to most other respiratory ailments, including bronchitis, asthma, laryngitis and pneumonia.
With care in the early years, good fortune, and the assistance of your veterinary practice, your Sheltie should live to enjoy a healthy and happy life.