Can chickens catch "The Common Cold"?
I have read for years on different chicken diseases. For instance, MG. In the past, I had chickens that were occasionally sneezing, some breathing that sounded congested, a little swelling around their eyes. No exudates, no deaths, just a couple weeks of being less than healthy. The last time this happened it was a batch I had raised here on the farm, so of course they were encountering something present locally, either from the older chickens or wild birds. The state vet said if I tested for MG it wouldn't say much since most backyard flocks probably have it. So would MG ever be so mild as to present as a simple cold? Are there any other respiratory diseases that aren't very serious that we would encounter? Do chickens catch plain old viral colds?
Fauquier County Virginia
In my experience, if chickens show mild signs as you describe, and it gets better or comes-and-goes, it is often caused by MG. There are different strains of MG that range from causing no respiratory signs to causing rather severe problems. MG can be transmitted from older birds presently on the farm to younger birds being brought in. Sometimes with the milder strains, the chickens won't show anything until under stress, such as cold weather, heavy egg production, etc. MG is also egg-transmitted, so if you use fertile eggs from older hens in your flock for incubation and hatch out your own chicks, the chick can have MG.
There are a number of other bacterial and viral agents that can also cause respiratory problems (i.e. "cold" symptoms) in chickens, such as infectious coryza (Avibacterium paragallinarum), infectious bronchitis virus, and Newcastle virus. Often, the only way to find out the definitive cause is submitting some birds showing clinical signs to a veterinary diagnostic laboratory.
Thank you, that's pretty much what I expected to hear. Is there a vaccine available to small flock owners, and if so, would it have to be done yearly or with each new batch of chicks? And, in a multi-age homestead poultry flock, is there any point to vaccinating? Would it at least be a help to new chicks raised from the eggs? Would it protect against worse strains of MG? Would it be worthwhile to protect other people's flocks in case I sold someone chickens? I'm willing to vaccinate for the greater good, even if my chickens seem to be ok.
Before starting any vaccination program it is imperative to first get a definitive diagnosis of what is going on. The primary rule of instigating any disease preventive measure is to first, do no harm and second, make sure you don’t introduce something to your premises (or your neighbor's!) that’s not already there. As long as your flock is not experiencing severe respiratory signs or severe reproductive problems, such as less-than-tolerable egg production, chicks with respiratory signs, vaccination would be of minimal benefit and may in the long run be detrimental. With live vaccines of any kind, there is always the potential of unexpected results depending on age of bird, flock health status, strain of vaccine used, and degree of stability not revert back into a disease-causing organism itself. If you feel you have a sub-optimal situation that you think needs improvement, you might wish to consult with your local veterinarian to work out a comprehensive health program.