It could be a number of issues. Bad habit can be one of the problems. But, yes, It can also be due to poor nutrition. They may be lacking something in their diet. I see this mostly with so-called Gamecock feeds that are heavy in grain, but have little or no pellets. Providing a good source of high protein pellet is a good practice. The pellets are a complete feed, and have everything the birds need.
My feed consist of 20 percent protein pellets and the pellets are half the feed. Make sure not to use lay pellet. It must me a high protein pellet, such as a breeder pellet or game bird pellet (turkey or pheasant).
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