the rot you are describing on the crop of the pigeon is a mite the feathers will not repair/replace until the moult it is not harmful and will not harm the pigeon or affect its ability to fly or race had several pigeons with same problem last year it has returned in 1 this year about 1 week ago the pigeon scores in combine last year at 400 miles with this bald spot on crop and raced yesterday in trying conditions back on its perch last night hope this helps if your still worried seek a vets opinion gl gm
