Upgrading Your Pasture: The Protek® Advantage

Tall fescue has been the forage workhorse of “Fescue Belt” pastures since the release of Kentucky 31 in 1943 by The University of Kentucky. Its persistence, palatability, and productivity have made it attractive to producers throughout the country for decades, but the opportunities for added animal performance may be left out to pasture without adoption of improved tall fescue varieties.

The many attractive features of tall fescue don’t come without management complications, which are largely associated with its natural symbiotic relationship with the Neoptyphodium coenophialum fungal endophyte. This endophyte lends to tall fescue’s persistence in tough environments like drought and heavy grazing, but can also significantly reduce animal performance. The answer to this issue is a novel endophyte.

Tall fescue endophytes are complicated, like a roommate that cooks, cleans, and pays their share of bills, yet also drives you a little bit crazy and steals your leftovers. There is a reason symbiosis occurs in nature, and this is just one example of a relationship that has given Kentucky 31 an advantage over time.

The endophyte that lives inside of Kentucky 31 produces ergovaline, which causes vasoconstriction in livestock. Vaso {blood vessel} constriction {gets smaller} means that blood flow is reduced to extremities like feet, tails, skin, and even reproductive structures. Chronic exposure to ergovaline can lead to fescue toxicosis which can cause "fescue foot" (feet and tails going necrotic and falling off), the loss of ability to shed the hair coat or an overall rough hair coat, as well as overheating and loss of fertility or spontaneous abortion of calves/foals. Because livestock will feel overheated, they will spend their time in the shade or in water sources rather than grazing, which can lead to weight loss and other stress-related illnesses.

However, as mentioned earlier, the endophyte infection in Kentucky 31 does lead to positive forage outcomes, which is why eliminating it completely isn’t the answer. Along with providing drought and pest resistance, it helps the plants tolerate heavy utilization. In addition, the livestock grazing this forage are forced to self-regulate, especially in tough weather conditions which allow the stand to rest and recover. This is why advanced technology is required when creating improved varities that have both improved persistence and animal performance.