Parront
Crossing the Road
Now that you mention it, the vet offered me a hormone treatment for my bird which had egg laying difficulty. I treated the problem with diet and exercise, and less light. I keep my parrot on a less than 12 hour of light schedule. I bet that would cause less crowing, too. Bird hormones are reduced in winter, so for my bird it is always winter. I put Dylan to bed at 6pm in her cage in a dark closet. I wake her up at 7 am. I only got 1 egg last year, and she was able to lay it, due to higher calcium pellets and more exercise. Might not eliminate crowing, but could reduce it while the OP looks for other options.From what I heard not, it works on adult roosters as well, is easily done without endangering the roosters life and does not cost much.
It's the same hormonal implants they use on male dogs for chemical castration.