This swab thing to diagnose what your chickens have is kind of confusing. What does it test for? A good friend is chief of microbiology at the local medical center. I did a nasal and pharyngeal swab recently on a chicken of mine that had a hiccup sound which I think is a chicken sneeze. It came back negative for everything he tested it for, but he told me that it is very difficult to get a positive culture for MG (mycoplasma) even in human beings. Most reports I have seen say that state labs have to perform necropsies and examine tissues and the whole respiratory tract to make any diagnosis, and sometimes I wonder if it is just opinion. Anyhow I would be surprised if there were such an easy test for CRD or MG like a swab, or more people would know about it.