I was looking for something else and came across this:
If you have a serious problem with thin-shelled or shell-less eggs, or a marked reduction in egg production, then you could be dealing with EGG DROP SYNDROME. I would not worry about the occasional thin-shelled or shell-less egg that comes at either the beginning or the end of the production season, nor the occasional less-than-perfect egg that is produced by a young hen when she comes into first egg (sexual maturity). Egg Drop Syndrome (EDS 76), should be considered though when you have a chronic problem in your flock in terms of egg quality or quantity especially at the height of production.
EDS 76 is caused by a duck adenovirus and is typically spread vertically, although the incidence of lateral spread does exist. The virus affects the pouch shell gland, which is responsible for producing the eggshell.
EDS 76 is not typically a big problem with domestic ducks or geese, which are natural hosts, but when affected through drinking water contaminated by feces, chickens can experience a profound affect on their egg production. Although the virus doesnt actually spread through the feces, what happens is that there could be exudates from the oviduct, which finds its way into the feces.
There are several things you can look for in the eggs that your hens produce to determine if youre dealing with an EDS 76 problem in your flock.
A loss of pigment in an otherwise brown or dark-shelled egg is one. Thinning at the pole of the egg is another. This is when the egg appears normal except for an appearance of thinning or translucence at the large end of the egg. When pressure is applied, the shell will break at this point first. Eggs that are thin-shelled and fragile overall is also a sign. Sometimes these eggs will feel like sandpaper to the touch. The most noticeable signs though are in the soft-shelled, or shell-less eggs. Sometimes these are hard to detect because the hens typically eat these before you see them. Look for the shriveled membranes in their litter theyll leave those. Otherwise, check early in the morning before the hens have a chance to eat the shell-less eggs.
Although a loss of appetite and dullness can occur, affected hens typically remain healthy otherwise. It can become a serious problem for the breeder, but if youre just keeping a little backyard flock for fun, then EDS 76 is not something that I would consider serious as a pet owner.
If you are a breeder and you have EDS 76 in your flock, then you can, over time, systematically eliminate the virus from your flock. Not all hens will actually receive the virus vertically, and as soon as you can identify them, you can slowly eliminate the problem. But while youre undergoing this process, you must make sure that you dont reinfect your flock through other means.
There is no known treatment for Egg Drop Syndrome. Some breeders simply live with the results of EDS 76 in their flock. Hens will appear healthy and happy whether they produce good eggs or not. Ducks that are infected and are hosts of EDS 76 show almost no signs of it and their eggs are usually good. This makes it even more difficult to identify the ducks or geese that are carriers.
Egg Drop Syndrome can be quite frustrating to the serious breeder. If it becomes a real problem for your breeding program, then vaccination is always an option. The vaccine lasts at least one year. Revaccination is usually necessary every year afterwards. Initial vaccination occurs between 14 and 16 weeks of age. Adults not previously exposed to EDS 76 can be vaccinated as well, but must receive a booster each year also. Most people find this to be quite an ordeal though when you consider the expense and the stress on the birds for something that is not life threatening, and does not carry any human health risk.
I think it's more of Kitty's contretemps, but you never know either...
Glad to hear that your ladies seem to be doing alright, Cyn and Zanester too.