Plague cows are cows infected by a plague that recently beset the desert city of Sophanem. They are one of many plagues set upon the city by the Menaphite goddess Amascut, more commonly known as "The Devourer".
Amascut, in an effort to cause more destruction, recently set a number of plagues on Sophanem, including swarms of locust and a disease that causes the victim to develop spots on their face. The cows too have become diseased, although with a different illness. Though not as severe as some of the plagues, they have reduced trade and supplies within the city.
Infected cows develop pale brown blotches on their skin, and generally take on a sickly green colour. Their milk is no longer safe to drink, coming out thick and putrid. Because of this, they cannot be milked by players. As their beef can also be contaminated, they cannot be killed either.
Attempting to pet them will result in one of the following messages:
"Awww, look at the poor sick cow. We'd never make a burger out of you."
"Don't worry cow, I'm sure somebody will find a cure for this plague soon."