If you asked me before I got pregnant, I would have told you, "Yes, animals can sense major changes like pregnancy." If you had asked me a week ago I would have said if they do, none of our animals have that sense, or they just don't care.
Tonight I sat down to pet our dog Sophie because she kept following me around wanting attention. (This is unusual by itself because she goes to Derek when she wants loved on, not me!) As soon as I sat down she buried her nose in my stomach and started sniffing. It was almost funny. She never does things like that.
At least I know one of the fur-children cares enough to say, "I know something is different even if I don't know what exactly it means!"