| F.N. Thompson, J.A. Stuedemann, and N.S. Hill |
| Authors are professor emeritus of physiology, College of Veterinary Medicine University of Georgia, Athens, Ga 30602, animal scientist, J.Phil Campbell, Sr., Natural Resource Conservation Center, USDA-ARS, Watkinsville, Ga 30677 and professor Department of Crop and Soil Sciences, University of Georgia, Athens, Ga 30602. |
Abstract |
| The greatest anti-quality associated with eastern temperature pasture grasses is the result of ergot alkaloids found in endophyte-infected (Neotyphodium ceonophialum) tall fescue (Festuca arundinacea Schreb.) The relationship between the grass and the endophyte is mutalistic with greater persistence and herbage mass as a result of the endophyte. Ergot alkaloids reduce growth rate, lactation, and reproduction in livestock. Significant effects are the result of elevated body temperature and reduced peripheral blood flow such that necrosis may result. Perturbations also occur in a variety of body systems. Planting new pastures with seed containing a "non-toxic" endophyte appears to be a potential solution. Ergotism results from the ingestion of the scelerotia of Claviceps purpurea containing ergot alkaloids found on seed heads. Ergotism resembles the effects of endophyte-infected tall fescue. Endophyte-infected perennial ryegrass (Lolium perenne L.) contains ergot and lotirem alkaloids that result in reduced growth and tremors. Reed canarygrass (Phalaris Anundinacba L.) contains tryptamine, hordenine and gramine alkaloids that reduce growth. Annual ryegrass (Lolium multiplorum L. may contain galls with cornetoxins which result in neurological signs. |
| Key Words: tall fescue, ergotism, perennial ryegrass, reed canarygrass, annual ryegrass |