Pasture and Hay for Horses

• Basics of Horse Nutrition
• Pasture for Horses
• Hay for Horses
• Health Concerns when Feeding Forages to Horses

Download the Pasture and Hay for Horses document in Adobe PDF format.

Additional pasture information via the Forage Information System (FIS)

Health Concerns when Feeding Forages to Horses

Horses are extremely susceptible to molds, fungi, and other sources of toxic substances in forage. Mold problems generally occur in hay that has been baled at too high a moisture level (20% or more) without the use of a preservative. This is especially a problem with first cutting hay because it is harvested during a period of time when it rains frequently and the weather conditions are less than ideal for hay drying.

Always use clean, unmoldy forages when feeding horses. In addition to molds and fungi, some forage species contain chemical compounds that can have negative health effects on horses.

• Sudangrass and sorghum-sudangrass hybrids contain compounds which can cause muscle weakness, urinary problems and death in severe cases. Do not feed these grasses to horses!
• Older varieties of tall fescue contained an endophyte fungus that could cause severe health problems if horses have only tall fescue to eat during the summer months. Mares are especially sensitive to the health problems associated with tall fescue. On pastures that contain endophyte infected tall fescue, remove mares from the pastures during the last three months of gestation. Newer tall fescue varieties that are free of the endophyte fungus are now available.

Another health problem could occur when horses are fed hay that contains blister beetles. When consumed, the beetle causes irritation to the lining of the digestive tract which usually results in death. Alfalfa hay that has been produced in southern areas of the U.S. is most generally associated with the potential to contain blister beetles. Do not feed any hay containing blister beetles to horses! Poisonous plants in pastures or hay can be fatal to horses. Ornamental shrubs and nightshade are the most common poisonous plants in Pennsylvania. However, any plant that is known to be poisonous to other animals is probably poisonous to horses. Some poisonous plants are highly palatable and should be identified and removed from pastures. However, many poisonous plants are not palatable and horses will not eat them unless there is inadequate forage available to meet their needs.