swimming boxers
Our last five boxers loved to swim. Casey is the first boxer that we've had that was never in the water, but we got her when she was three. I still want to try to get her in, but I'm not hopeful that she will go.
Our other dogs all loved the water so much. One boxer, Ruby, used to go crazy whenever we went near a lake, she couldn't wait to get out of the car and jump right in. Another boxer, Prince, used to go out with the neighborhood kids down to the creek, (when we lived in Tennessee) and they taught him to grab the rope with his mouth and swing on the rope with them and drop into the water. He absolutely loved it and whenever he heard those kids coming he would go nuts trying to get out of the house. He finally learned how to open the front door himself so that he didn't have to wait for us anymore.

They were all great swimmers, and would swim out for sticks for hours if we let them.
Ruby would even jump off of the diving board with us. We were always going swimming, so whenever we got another dog, they just went swimming with us. They all learned as puppies.