Julie0477, I don't know all of the symptoms your birds are showing. If you are giving him the Bs and he is showing improvement....how long has he been getting them? Are all of the birds on the Bs? I'm not sure what else you have done. I be very tired tonight, sorry. Look, if you can afford the test, do it. Either on this one or another that is worse off. This will give you a snapshot of your flock. It may not be Marek's there, but again, it could very well be just that. Marek's does some funny things sometimes, a bird could be showing signs of paralysis only to get 'better'. Doesn't mean the disease has gone away, it doesn't, it just means that for whatever reason, the swelling or tumors that were causing the initial signs have gone away or changed somehow to allow nerve function again. I've seen it quite a few times with my own and still don't understand why this one and not that one. Resistance? Probably, only thing I can think of. My advice? I would get the test done for my own peace of mind. I would get the vaccine regardless and give it to all of them. It can only help with building a much better resistance in the birds. This is what I would do, you have to make your own choices because this is your journey.