I definitely can tell the Muscovy do not grow nearly as fast as mallard derived breeds at this point. But the Muscovy seem to be a lot more friendly than the mallards just with the little experience I have now. All the Muscovy run to us, and fairly calm when you pick them up and will sit on you, which the mallards ones just seem a lot more skittish, even with just as much if not more handling even. We are really enjoying them and our little goslings. The sexing them part is definitely the hardest part of the Muscovy it seems. I can tell you 3 of the females of the mallard derived, however the Muscovy just seems about impossible at this time for us even at 5 weeks old. I do suspect 2-3 are female, but all the markers I have seen to help identify, just is a bit confusing. Seems we are talking subtle differences, that maybe with more experience with breed would be more pronounced to us and not so difficult. The only reason really we care is for naming purposes at this time. I can say there is like 2 definitely looks a bit smaller than the rest, yet the other day it appeared 3 looked more like a v on tail and 3 more of a U. Problem is supposedly the males have a flatter bill? Well I can not really notice much of a difference in them. They are all starting to get growth near their face and bill, but from reading the male is supposed to start getting it around the eye first, yet none yet seem to be. Bottom line is there any more definitive ways that are easier to look at to really sex these sweet ones, without vent sexing and flat out just waiting, which I know later I should know?