Since I am one of the ones that tested positive, so I KNOW I had MG in my flock, and I have a very long background in livestock and a degree in biology, here's what I know. These are things I know, not surmise:
- MG makes your birds sick, and in some flocks it does decimate the flock. We lost dozens of young chicks and adolescents and we had very sick and miserable adults. It doesn't kill very many adults, but it is horrible for them to go through. If you have an adult with other issues (for example, if you've just had a heat wave or cold snap and their immune systems are not great, or if you have mites, or if you have coccidia) the MG can without a doubt kill them. And it DOES kill (and MS also DOES kill) chicks and adolescents. The chicks get very stunted and weak and the adolescents get the swollen eyes and can't eat. It doesn't go away quickly unless you medicate them, and once you've medicated you're going to have to keep watching and keep medicating. We had many birds go through two and three cycles of Denagard, six weeks apart. MG ruins your feed conversions - in real life, that means your chickens are always skinny and sad and they lay like crap. They don't thrive - they may live, but they don't thrive.
- MG is a very common disease, but it's not so common that everybody has it and we're only realizing it because we're testing. If that were the case, the Dept. of Ag wouldn't even bother. I was told point-blank that this is a spike in incidence and that's why they're concerned about it and testing and contacting people. Yes, it CAN come in on a sparrow, but by far the most common carriers are chickens and that's how it moves from flock to flock.
- MG has a very limited ability to move through air. Most of the time it's chickens sharing waterers (the nasal mucus and mouth secretions carry it) and people hatching infected eggs that carries it through a flock.
Once I knew I had MG, everything fell into place. Before that, I honestly just thought I was having "a bad month" or "a bad winter" or "a bad few months." We were coming up on "a bad six months" when we got them tested and they all came back positive. Couldn't seem to keep chicks healthy, couldn't seem to have the adults get through stress easily. Eggs would go down to zero at the drop of a hat. The adolescents were skinny. They'd sneeze and wheeze, then seem to get over it, then a few weeks later be sneezing again and shaking their heads. We changed food about five times, we wormed, we culled anything weak, we treated with Baycox - we could never quite get a robust happy group. That's what is meant by MG "not being a serious disease." No, it won't come through and kill all your birds in a weekend. Will it make you and your chickens miserable and never go away, never let them really thrive again? Yes, absolutely it will.
