Of course animals are sentient. The arrogance of people to think we are the only animal capable of sentience, or intelligence of any kind. We have evolved to be better at some things than other animals, but they are all smarter than we are in ways. Dogs know more about smells than we do, remember a smell for life. They have a better sense of direction, as many wild animals do, and are better at remembering landscapes and vast wild areas.

You get into cold blooded animals and it changes somewhat, but all warm blooded animals are capable of more than we give them credit for. Cold blooded probably too but in a different way.