I read an interesting case report in JAVMA - "Animal Behavior Case of the Month."
A 2 year old Border Collie that was evaluated for behaviors including spinning in circles and chasing lights and shadows.
Readers of this Forum might find the case report of interest. Here is more information about Vitreous Degeneration - a condition that is fairly commonly seen on ophthalmic examination in dogs. Humans with vitreous floaters typically report seeing spots with (or lagging) ocular movements - akin to seeing a fly passing by - especially in ambient or bright light conditions. Although the literature does suggest vitreous abnormalities as a possible cause of "fly biting" behavior in dogs, in my career, I have never seen it. I can recall a few patients where a client may have indicated a change in vision, but nothing that created a problem behavior for the dog.
