Have Animals Got Feelings?

I think that animals must have feelings because I have got two dogs and I can see them everyday. Sometimes they are happy or sad and when you give some food to one of them the other gets jealous. And I see that they love us two because when member of my family is ill, dogs lick him and they are really kind to that person. But you can see that whereever, animals are nicer with some people than with other kind of people. For example, a police-dog is happier when he finds a lost person or when he helps to find drugs they look happier. Another reason is that they feel sad when they make a bad action and they can also cry.