Pic by @Quail27

A fairly common problem with growing ducklings and goslings is foot and leg problems, caused by incorrect feeding, or more specifically, lack of usable Niacin (B-vitamin) their diet. Niacin is a critical vitamin required for the correct development of ducklings and goslings. In fact, waterfowl have a higher requirement for niacin (also called nicotinic acid) than chickens, which means certain poultry starter feeds, for example one formulated for layers, will not be suitable for ducklings, unless niacin is supplemented. Niacin deficiency can lead to problems such as stunted growth, lameness, bowed legs and swollen joints. Ducklings and goslings that have access to the outdoors and good sources of plants and insects seldom have this problem, but it may show up in brooder raised ducklings and goslings. To prevent this make sure the ducklings are fed a proper, nutritionally balanced starter feed with adequate levels of niacin.

Minimum basic nutritional requirements of ducklings:
Protein (%)201716
Calcium (%)113
Fat (%)555
Methionine (%)0.350.30.3
Phosphorus (%)0.450.40.4
Manganese (mg/kg)605040
Niacin (mg/kg)554055
Pantothenic acid (mg/kg)151020
Pyridoxine (mg/kg)333
Riboflavin (mg/kg)10610
Vitamin A (mg/kg)310017204130
Vitamin D3 (mg/kg)30022.562.5
Vitamin K (mg/kg)2.522.5
Energy (kcal/kg)285028502650

What to do if your ducklings or goslings are exhibiting signs of niacin deficiency?

Ducklings/goslings exhibiting niacin deficiencies can be given 100-150 mg. niacin (crush tablet) per gallon drinking water. **Drugstore Niacin can cause liver damage if overdosed to the point that it is toxic, so stick to the recommended dosage and don't think that more is better!

Brewer's yeast is an excellent, safe source of niacin:

According to Storey's Guide to Raising Ducks: "5 to 7.5lbs (2-3 kg) of livestock grade brewer's yeast per 100 lbs (37 kg) of chicken feed or 2 to 3 cups of brewers yeast per 10 lbs (3.5 kg) of feed..." We mix small batches of 1lb 4oz of feed with 1/4cup brewers yeast from the health food store.
**Note: There is about 5mg niacin per 15 grams (one tablespoon) of human grade brewers yeast. Livestock grade brewers yeast is less concentrated and contains 1.5 grams of niacin per tablespoon only.

Depending on the severity of the problems, ducklings/goslings should recover within a few days of starting treatment. If left untreated, they can be left crippled or stunted and some may die, due the inability to move around freely.

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