ID-221: Fescue Toxicosis in Cattle

Megan Romano, Michelle Arnold, Ray Smith, Krista Lea | Feb. 13, 2025 (Minor Revision)

Tall fescue [Lolium arundinaceum (Schreb.) Darbysh., previously known scientifically as Schedonorus arundinaceus (Schreb.) Dumort.] is a cool-season, perennial grass (Figure 1). The Continental type, most notably the Kentucky-31 variety, is frequently infected with an endophyte (Epichloë coenophiala). An endophyte is a fungus that grows inside the grass, specifically within the intercellular spaces of the leaf sheaths, stems, and seeds, and is invisible to the naked eye. The plant and fungus have a mutually beneficial relationship, wherein the plant provides the fungus access to its nutrients and a means of asexual reproduction through infected seeds. In turn, the fungus produces compounds called ergopeptine alkaloids that increase the plant’s vigor by making the plant more pest- and drought-resistant and more tolerant of other adverse soil and environmental conditions. Although advantageous to the plant, ergopeptine alkaloids adversely affect the health and productivity of grazing livestock. Ergovaline is the most abundant (more than 90 percent) and most toxic ergopeptine alkaloid in endophyte-infected (E+) tall fescue. The highest alkaloid concentrations are found within the seedheads and in the bottom few inches of the plant.

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AGR-281: Improving Kentucky Horse Pastures

Chris Teutsch, Krista Lea, Ray Smith, Bob Coleman | Feb. 13, 2025 (New)

For many horses, quality pasture can provide almost all nutrients needed for maintenance or light work for much of the year. Pasture reduces the cost of keeping horses while providing safe footing and minimizing impacts on the environment.

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AGR-275: Tall Fescue Novel Endophyte Varieties and Establishment for Livestock and Horse Farms

Krista Lea, Stephanie Smith, Ray Smith | Nov. 2, 2023 (New)

"Endophyte" refers to a fungus that lives within the fescue plant, meaning it cannot be seen with the naked eye. The endophyte found in tall fescue is beneficial to the plant: It gives tall fescue insect resistance, enhanced grazing tolerance, and greater persistence in stressful environments. The major disadvantage of some of the endophytes of tall fescue is that they produce toxic alkaloids that have detrimental effects on many types of livestock.

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AGR-268: Evaluating Cool-season Perennial Grass Pastures using the UK Horse Pasture Health Score Card

Krista Lea, Ray Smith | Dec. 19, 2022 (New)

Providing quality forage is essential to horse health, and pasture can provide a significant portion of the horse's forage needs. Objective evaluation of a pasture's condition can help determine appropriate pasture management practices. The UK Horse Pasture Health Score Card can be used to evaluate horse pastures and determine what improvements should be made.

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AGR-264: Improving Kentucky Small Ruminant Pastures

Jimmy Henning, Krista Lea, Ray Smith, Chris Teutsch | Apr. 2, 2021 (New)

For many small ruminants, quality pasture can provide almost all nutrients needed for maintenance or light work for much of the year. Pasture reduces the cost of keeping livestock while minimizing impacts on the environment. Below are some guidelines for improving pastures.

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AGR-222: Estimating Carrying Capacity of Cool Season Pastures in Kentucky Using Web Soil Survey

Krista Lea, Ray Smith | Aug. 10, 2016 (New)

While many factors influence how many animals a farm can carry, soil type has a major influence and should be considered when purchasing, leasing, planning, or managing livestock on pastures.

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AGR-221: Wildlife Benefits of Switchgrass Production in Kentucky

Tom Keene, Krista Lea, Laura Schwer, Ray Smith | Jul. 26, 2016 (New)

Switchgrass is a versatile grass that can be utilized for forage or biomass production. Establishing and maintaining switchgrass is also beneficial to many types of wildlife by providing suitable habitat and cover.