It was only poopy that once, and hasnt been like that for a while. I will give him a warm bath after dinnner. Or in the morning. He has been better now, not that stuffy and more.
Pasty butt can always happen. All you do is get a wash cloth dip it in warm, soapy water. Wring the cloth out and get the duckling and slowly rub the area where the poo is. It will slowly come off. You may have to repeat this throughout the day. This could also be why he/she is not growing like the others since it's not eating because it can't get its poo out. After you are done I would get another clean, dry towel to dry his bottom then put him back in the brooder.
I've had my fair share of pasty butt chicks and its very labor intensive to clean their bottoms throughout the day, but they end up getting stronger and stronger every day!
Pasty butt can always happen. All you do is get a wash cloth dip it in warm, soapy water. Wring the cloth out and get the duckling and slowly rub the area where the poo is. It will slowly come off. You may have to repeat this throughout the day. This could also be why he/she is not growing like the others since it's not eating because it can't get its poo out. After you are done I would get another clean, dry towel to dry his bottom then put him back in the brooder.
I've had my fair share of pasty butt chicks and its very labor intensive to clean their bottoms throughout the day, but they end up getting stronger and stronger every day!
This sounds very similar to what one of my three ducklings had. Except for she had a niacin deficiency as well. I gave her electrolytes and vitamins and she started growing pretty quick except she is permanently stunted.
This is what she looked like compared to her siblings. She's still significantly smaller but not too much.
Hope you figure out what's wrong and can help get your baby to feel better!