Due to a shortage of wheat straw in the United States, more and more dairy and equine operations are switching to rye straw for bedding. According to experts at the UK CAFÉ,  this can be a good option, but there are several unique considerations with rye straw. Unlike wheat, where the grain is harvested first and the remaining stems are cut and baled, with rye, the whole plant is usually harvested and baled. This means the seed heads are still on the plant. The seed heads of rye have awns or appendages that may cause gum irritation. Another consideration with rye straw is the risk of ergot. Ergot is caused by fungi and is poisonous to livestock when infected cereal grasses are consumed. In horses, the most common signs are lactation failure or deficiency, prolonged gestation and fertility problems and in dairy cattle reduced milk production.  Ergot bodies, look similar to mouse droppings and occur in the place of healthy seed. Often ergot bodies fall off during the raking and baling process. However, inspect rye straw being used as bedding to ensure it is free of ergot bodies. If ergot bodies are found, use caution because of potential toxic concentrations of ergot alkaloids. Additional info: https://www.ag.ndsu.edu/pubs/plantsci/crops/pp551.pdf.

~ UK CAFE Press Release June 7, 2016