Johnes is the hell of all diseases I have been testing since 1996 and have had clear tests four times since then. I think I have a lid on it now as had six or seven clear tests over these last years. I my opinion care needs to be taken over the following dung test after a positive blood although the dung test comes back clear it really just means she’s not shedding and depending how much you want to be free of this disease she still needs to go. Dairies can be a source of infection but some are doing very regular milk tests which can mean it can actually be picked up quicker than the annual blood test. Again in my opinion there is no shortcuts with Johnes we’ve used the saying for years if in doubt she’s out !!
