собак appears to be genitive, rather than animate accusative. Katzner's dictionary says that the "objects" (to be feared) of бояться are in genitive case.
That raises a question: can Russian direct objects be genitive? Feared things (animate or inanimate) are direct objects in English, but since they're not in Accusative in Russian, are they actually direct objects - or something else?
If they're not direct objects, then what are they?