The 32 countries that have formally recognized non-human animal sentience include the European Union, Switzerland, Chile, Australia, New Zealand and the United Kingdom.
Ever since I looked at the dictionary definition of the word, I have thought animals had sentience. It just means the thing has senses and some awareness of the world around them. Yet it's more commonly used to describe the difference between humans and non-humans, which is what the word "sapience" is supposed to mean. It's like at some point, we started using the wrong word.
I've always understood sentience as the ability to sense oneself, i.e. a being's capacity at introspection and awareness of one's own existence as a separate experience from other beings.
Many mammals and birds tick this box, some more than others.