I don't think most animals do "it" for pleasure. Some of the ways animals mate look quite painful. I mean a male cats penis is supposed to be barbed, dogs get stuck together, horses injure themselves sometimes while at "it". Doesn't sound much fun to me.

And 30 minutes for gods sake. Sounds like it might cross the threshold of pleasure to pain but then again, I'm not a pig so maybe they do enjoy it.

But then again there do seem to be "gay" animals so maybe they do enjoy "it". Or maybe they don't realize they are mounting the same sex.