From Ralph Hancock
The Roman writer Vegetius mentioned a cattle disease called mania (7 April, p 21). He described it only briefly, at the end of a list of diseases including elephantiasis: “There is mania, which deprives well-fed cows of sense, so that they neither hear in the usual way, nor see; from this affliction they quickly die, however happy and fat they might have looked. All these diseases are full of contagion, and if they affect one animal, rapidly spread to all…”, and he goes on to recommend isolating the affected animal. At http://tinyurl.com/26kx7h you can see this in Latin.
This sounds quite like one of the group of diseases called “staggers”. Their symptoms are increasing paralysis and blindness, collapse, convulsions and rapid death. Their causes are dietary: magnesium deficiency when cattle are turned out to spring pasture, calcium deficiency, selenium poisoning, or infection of fodder by ergot fungus. Ergot is thought to have caused medieval outbreaks of dancing mania, affecting whole villages. Since all the herd will be affected at the same time, the disease may appear to be contagious.
London, UK
