And Hershey, like many blind dogs, was willing. I ve had arguments with owners who refuse to accept that their pets are blind. Part of that disbelief is due to the way dogs deal with blindness. For a human, sight is the primary sense, Dr. Marlar said. For a dog, the primary sense is smell, followed by hearing.
Vision is a dog s third most important sense that s relatively low on the list.
Dogs also possess a skill called cognitive mapping, Ms. Levin said. It s the same instinct that allows them to find an object they buried weeks ago. They have the house and yard mapped in their mind, and they can run full speed around the house. If a dog gradually goes blind if, for example, it loses sight in one eye and then starts losing it in the other owners might not even notice until the day they move the furniture and the dog starts walking into things. The eyes Ms. Worden referred to were startling in the gray canine face milky white with a bluish glow, streaked with radiating glimmers like a star sapphire.