I have a two year old Jacob Sheep ewe that is shedding her fleece. She was shorn last year with no issues. Is this a sign of a disease or deficiency? No one else in the flock is having this issue. She has lost about 1/2 of her fleece so far.
Has she lambed or been ill lately? Does she seem really itchy?
Wool loss like that is usually due to a break or weakness in the wool that is caused by a stress. The stress could be from lambing or illness. If she seems itchy and her wool is coming out in scraggly chunks, it could be due to lice.
She has never lambed. I don't see her scratching, so I don't think she is itchy. I would think of it was lice the other six sheep would be affected, as they are keptin a pin until we let them out to graze. The wool is missing from both sides and comes off in big chunks, often on thorns, but I've seen patches in their pin as well.
I have a couple of wool ewes who do this every year without any illness. It's happening right now to 2 of them and is characterised by a fleece about 0.75 inches already being present under the 'old' fleece. They both usually end up with fleece which stays on over the top of the back legs such that they look like they are wearing jodhpurs, but never go bald.
It is true, though, that any severe illness causing fever can lead to the whole of the wool being lost without a new fleece being present underneath. It will grow in, but they can get hypothermic in cold weather.