Here is a list of common diseases that plague poultry, along with some treatment options. I hope this helps.I love our sweet little Legbar, but I don't think she is very healthy. I got her for blue eggs, and being able to know she was definitely a pullet. Since her comb grew she has always done a lot of head shaking, which I attributed to her comb or crest bothering her. Now I'm thinking something else is wrong. She is 8 months old and still not laying. She has heavy breathing and when I listen to her back it sounds liquids or like if you inhaled and exhaled into a paper bag.
For Legbar owners,
do your birds shake their head more than other breeds?
Do you find possible health defects in the breed?
Do they sometimes take more than 8 months to,lay eggs?
I don't know if I'd get another, not only because I think she's unhealthy, but because the others seem to pick at her extra large comb. As far as personality, though, she is one of the calmest we've had.
http://www.poultrysupplies.com/index_files/Page398.htm
I did not notice this line (bold line) until reading the response from @DocumentedPure , I do not think you have pure Legbars @amanda1 . If you did the hen would not have a large comb. The combs on Legbars are relatively small with the crest taking up much of the space the comb would occupy.
The actrions and laying you describe are not traits of legbars or mine anyways. All of mine lay around that 25 week mark.