I have noticed something unusual when I play fetch with my six-year-old Labrador. If I throw the ball a short distance, he has no trouble retrieving it.

However, if I use a bat to send it really far out, he seems to lose sight of the ball. He heads out in the right direction, but then has to spend a long time searching for it. Could he be nearsighted? Is there anything I can do about this?

Damien Santa Barbara, CA

Your dog could be nearsighted. In fact, both nearsightedness and farsightedness have been documented in dogs.

Since they cannot read eye charts, animals’ eyesight cannot be measured using standard human vision tests. However, it is possible to measure nearsightedness and farsightedness using a series of lenses and a device called a retinoscope. Studies have been done on enough dogs to show that toy poodles and possibly English springer spaniels are predisposed to nearsightedness. Australian shepherds are more likely to be farsighted. Labrador retrievers most frequently have good vision, but there can be exceptions.

Testing and treating for nearsightedness is possible through veterinary ophthalmologists (veterinary eye specialists). Believe it or not, some dogs have been fitted with contact lenses to resolve the problem. I swear I am not making that up. Laser eye surgery probably is on the horizon.

Even if you are not interested in going to such extreme lengths to test and treat your dog’s vision, you should take him to the vet if you are worried about his eyesight. A number of problems besides nearsightedness can affect vision. Some of them can be serious. A veterinarian should be able to determine whether there is anything to be worried about.