Obsessive compulsive disorder appears on the Border Collie's health list alongside epilepsy and cancer, and that placement is not a filing error. Compulsive behaviour is common enough in the breed to be treated as a clinical issue.
The forms it takes are recognisable: chasing shadows and light reflections, spinning, tail chasing, flank sucking, fixating on water from a hose or a puddle, and staring at or stalking objects for long periods. It begins as a self-soothing outlet for unspent drive and becomes self-reinforcing, and at the far end it displaces normal behaviour — a dog that will not eat, rest or engage because it is patrolling a wall for a light that appeared once.
The critical practical point is that these behaviours are far easier to prevent than to treat. Prevention means not starting them: no laser pointers, ever; no encouraging shadow or reflection chasing because it looks funny; managing access to hoses and sprinklers; and above all meeting the exercise and mental requirement so the dog is not looking for an outlet. Once established, treatment usually involves a behaviourist, environmental management and sometimes medication, and progress is measured in months.
Cerebellar abiotrophy is the other neurological entry and is quite different — an inherited degeneration of the cerebellum causing progressive loss of coordination, typically appearing between about six weeks and two years as a wobbly, high-stepping gait, tremors and difficulty judging distance. There is a DNA test in the breed, so a breeder should be able to give both parents' status.
Epilepsy, allergies, hypothyroidism and cancer complete the picture, alongside the eye and hearing entries covered below.
The Pit Bull's list is physical rather than neurological: hip and elbow dysplasia, skin allergies, heart murmurs, bloat, obesity, cruciate ligament disease, arthritis and cancer.