Use of nonergot alkaloid-producing endophytes for alleviating tall fescue toxicosis
Beef animals that consume pasture or hay containing tall fescue that has been infected with an endophyte are susceptible to tall fescue toxicosis
, which has various effects on health, production, and reproduction.
The same endophyte, however, has been associated with tall fescue toxicosis
(Hill et al., 1994) expressed, in part, as reductions in animal weight gains (Stuedemann and Hoveland, 1988; Fribourg et al., 1991; Schmidt and Osborn, 1993).
Consumption of endophyte-infected tall fescue, whether in pasture or hay, may result in "tall fescue toxicosis
." Tall fescue toxicosis
impacts health, production, and reproduction in livestock (Waller & Fribourg, n.d.), especially horses.
Ergovaline is used as an indicator of potential toxicity, with the realization that other ergot-like alkaloids (ergopeptine and lysergic acid derivatives) may contribute to tall fescue toxicosis
(West et al., 1998).
Ergovaline, an ergopeptide closely associated with tall fescue toxicosis
(Yates et al., 1985), is present in significant quantities in endophyte-infected perennial ryegrass (Rowan and Shaw, 1987).
These new Neotyphodium-free cultivars, initially released to prevent outbreaks of tall fescue toxicosis
(Hoveland, 1997; Latch, 1993), also lack persistence (Latch, 1997).
Most existing tall fescue pastures are infested with the endophytic fungus Neotyphodium coenophialum (formerly Acremonium coenophialum Morgan-Jones & Gams) (Glenn et al., 1996) which causes well documented signs of tall fescue toxicosis
(Paterson et al., 1995).