Several pregnant mares had mysteriously aborted their foals. There would be no return on an investment in an expensive breeding program. Beyond money spent, there was the loss of a year in the reproductive life of each mare. For now, there would be no opportunity for the farm to grow or profit. They called me after being told that the problem might be their pastures, specifically pastures that contained tall fescue.
Tall fescue is a common grass species used around farms.
It is a coarse clumpy grass that is very tough and excellent at erosion control. Unfortunately most old fescue stands contain a fungus called fescue endophyte fungus. This fungus produces a toxin that is harmful to animals that graze on it. Different species and breeds may vary in their sensitivity to the fungus. Pregnant livestock are the most sensitive.