Originally Posted by Amiga
Ducklings can get spraddle leg. Often leg problems are because some individual ducklings have a higher need for B vitamins, especially B3 (niacin).
I may not be on long enough to get your reply, so here are my thoughts.
Start B vitamin supplements a.s.a.p. If you have plain - plain - plain - not no-flush, not slow release, but plain niacin capsules, you can add 100 to 150 mg niacin per gallon of drinking water. I repeat myself because we can lose track of that important detail when worried about ducklings. I don't doubt your sanity or ability to read, I have just seen too many nervous duck parents lose track of that detail.
Another option is brewer's yeast. Not baking yeast, not wine-making or beer-making yeast, but brewer's yeast (also the very similar nutritional yeast is okay). Many duck folks use a tablespoon of brewer's yeast per cup of food.
Another option is B Complex capsules. Using the amount of B3/niacin as a guide, put 100 to 150 mg of B3 per gallon of drinking water.
If the problem is niacin or B vitamin deficiency, improvement is often seen within days.
Since the legs are already splaying, I suggest you use a hobble. Stoney's Guide to Raising Ducks has instructions, and I believe you can also find instructions on the poultrypedia podiatry page.https://sites.google.com/a/poultrypedia.com/poultrypedia/poultry-podiatry
Okay, now I have sent that first part, perhaps you can write about what kind of food they are getting, what kind of bedding they are on. She may need something more grippy, or it may just be she has a tendency to have this problem.
What breed is Cuddles? She's a cutie!
Does she get tub time? Always need to supervise ducklings in the water, of course. But tub time in water the same temperature as the brooder (have you read the Sticky on Raising Ducklings yet?) may help the leg problem. Water depth should be just up to her tummy. She won't be able to float for long, but any water exercise she can get will likely strengthen her legs. Constant supervision is needed, and they need to come out of the tub before they get too tired, then right back into the warm brooder.