That is so strange about the nutri drench I've used it for years on newly hatched chicks and ducklings and never seen it do this. but glad you found out the problem, great to hear the lil one has started to gain weight too. do they have water deep enough to wash their faces 24/7?Here's an update:
Yesterday afternoon I noticed 2 more doing the same thing as the tiny duckling. After watching them for a while I noticed that they were also the one's with the dirty faces. Upon closer inspection I noticed they all had plugged nostrils! Anything with a stuffy nose is going to mouth breath. The Nutri-Drench is sticky enough they were getting very dirty from it and it was also plugging their nostrils. So those 3 got put into a plastic washtub with a towel on the bottom and shown what fun it is to play in a bowl of warm water. 2 were willing participants and got cleaned up pretty nicely. The 3rd one didn't want anything to do with the water but I managed to get 1 nostril cleared so it's only mouth breathing a tiny bit now. I went back to the Save-A-Chick in their water last night and this morning since it's not sticky. I'm also going to try the face baths again this afternoon since these 3 don't seam to play in the water like the other 3 do that aren't having this problem.
I also weighed the tiny one that's been having so much trouble and it gained 4 grams overnight! It hadn't gained anything at all for 2 days so tiny as this may be it is gain and i'll take it.
Now I'm just praying this really was all that was wrong with them and that as they grow they discover water is super fun and keep themselves washed up better on their own. And hopefully the tiny one will keep gaining-it's got a LOT of catching up to do. We're also hopeful that once we get them onto a grower feed in a week or so that their growth will even out. There are huge growth differences in these babies so I'm inclined to think this food doesn't agree with all of them quite as well as it does for some of them. We were going to change them yesterday but the only options for us are in 50 lb bags and they are going to be 2 weeks old in a week so it would never get eaten up before they are supposed to drop down to a lower protein level.