If they weren’t vaccinated as chicks and growers, it’s too late now, I’m afraid. Chicks hatched and raised commercially in very large batches will be given a spaced-out series of vaccinations at appropriate ages, up to the point of sale at 16 weeks, but the vaccines are expensive for small-scale growers as they come in doses for 1,000 birds at once. Whilst it’s lovely for people to be able to raise their own chicks, it does come with some inevitable problems, not only what to do with the unwanted cockerels, but the possibility of spreading diseases such as bronchitis and Mareks disease to any flocks the young birds may be passed on to.
I hope and expect the black marks on your hens’ combs are, as suggested, basically just wear and tear, which will heal up if you can cut back the brambles and keep an eye on the activities of the cockerel. If he is unaffected, it looks very possible that he is contributing to the problem, or causing it. Two wives is not very many when it comes to sharing his energies!
Anyway, it’s lovely to have you on here, welcome to the Forum! Do please let us know how they get on. You may not have found the main Poultrykeeper site, which is a mine of information and very helpful about all sorts of problems. See
https://poultrykeeper.com/
and no other symptoms.
