[HairOfTheDog]

Did he mention worms? when was the last time she was wormed?

My vet book says: There are many causes of edema; it is commonly seen in gastro-intestinal conditions that damage the tract, which results in the leakage of material into the body, affecting the concentration of the blood. A common cause of this is worms, and a horse with a heavy worm burden will often get edema after it is wormed. Any condition causing inflammation of the blood vessels, such as infections or wounds, will result in edema.

[Rose of Sharn]

All of the horses are wormed regulary. So I dont think it can be that.