Pekin duck has curved back

[Leo.76]

Hello! It's been awhile since I've had ducks. I have 6 ducklings 2 are Pekin. They are about 5-6 weeks old. Today I've noticed that one of the Pekin ducks has a curved back or posture.
I feed all my ducks the same food; flock raiser with duck pellets which has plenty of niacin. I also feed them dried meal worms as that's their favorite. They also recently started to free range around the yard.

What can I do? Is this normal? It was perfectly fine a few days ago

 

[ruthhope]

Hi Leo.76

I can see the curved appearance of your ducks back in the photo. Have you felt the duck's back? Is it definitely a curved spine [kyphosis] or is there a soft lump over your ducks back?
I don't know what has caused this -- but it is likely congenital -- the duckling was born with it but it has become more pronounced as the duckling grows. I cannot find anything in quite a thorough search on line.

While I don't think it is a niacin deficiency, flock raiser pellets do not contain enough niacin for pekins; and some other ducks that individually have high niacin need, can also get deficiency if fed flock raiser alone. Your pekins need 1 table spoon of brewer's yeast adding to each cupful of pellets. Adding that amount of brewer's yeast will not harm your other breed of ducks as niacin is water soluble and their kidneys will excrete any un needed niacin in their diet. I sprinkle the brewer's yeast ontop of the pellets in the feeding bowl with a few mealies worms. My ducks love that!