Ungulates.

Having now had ice cream from three different mammals, I can say cow remains the best, followed by goat, with water buffalo coming in last. It's possible it wasn't that good a batch - given the relative fat content of the milks, I'd think the buffalo would be creamier and thicker instead of softer.

While I won't be rushing out to try it again for a while, I'm pleased that I've now got a list.