I see deer on the MUP I train on. I keep my eye on them as well as the other critters I see. It's no fun hitting any animal but the odds of getting hurt bad by hitting a deer are high.

I was taken down once by a duck. It got scared, took off hard, and flew right into my wheel taking me down hard. I ended up picking duck feathers out of my rear derailleur. My front wheel was bent so bad that I had to hit it against the side walk so it would be straight enough to pass through my forks. I took of the front brake so I could ride home.