Ergovaline is an ergot alkaloid produced by the symbiotic endophyte Epichloë coenophiala, which can colonize varieties of the cool-season grass tall fescue (Festuca arundinacea). It is the principle toxicant responsible for the vasoconstrictive and reproductive sequelae seen in "fescue toxicosis" in livestock which consume forage exceeding the threshold of toxicity established for this compound...

Ergot alkaloids in endophyte-infected (Neotyphodium coenophialum) tall fescue (Lolium arundinaceum) have been shown to cause a reduction in blood flow to the rumen epithelium as well as a decrease in volatile fatty acids (VFA) absorption from the washed rumen of steers. Previous data also indicates that incubating an extract of endophyte-infected tall fescue seed causes an increase in the amoun...

Molecular genetic techniques to precisely eliminate genes in asexual filamentous fungi require the introduction of a marker gene into the target genome. We developed a novel strategy to eliminate genes or gene clusters located in subterminal regions of chromosomes, and then eliminate the marker gene and vector backbone used in the transformation procedure. Because many toxin gene clusters are s...

the lpsa gene, a late acting gene in the biosynthetic pathway of ergovaline, a suspected causative agent for fescue toxicosis in cattle, has been cloned from neotyphodium lolii, an endophytic fungus of lolium perenne. in this study, a similar gene was detected in several strains of endophytic neotyphodium spp. isolated from grass hosts endogenous to iran using direct and nested-pcr assays. exce...

Tall fescue [Lolium arundinaceum (Schreb.) Darbysh; Schedonorus phoenix (Scop.) Holub] is the primary cool season perennial grass in the eastern U.S. Most tall fescue contains an endophyte (Neotyphodium coenophialum), which produces ergot alkaloids that cause vasoconstriction and could restrict blood flow to the fetus in pregnant animals. The objective of this study was to examine fetal growth ...

The Oregon State University Colleges of Veterinary Medicine and Agricultural Sciences instituted the Endophyte Service Laboratory to aid in diagnosing toxicity problems associated with cool-season grasses in livestock. The endophyte (Neotyphodium coenophalum) present in tall fescue (Festuca arundinacea) produces ergopeptine alkaloids, of which ergovaline is the molecule used to determine exposu...

Ergot alkaloids produced by the endophyte (Neotyphodium coenophialum) associated with tall fescue (Lolium arundinaceum) are implicated in the clinical signs of fescue toxicosis. These compounds were hypothesized to correspondingly affect foregut vasculature. The objective of this study was to determine vasoconstrictive potentials of ergovaline, ergotamine, ergocryptine, ergocristine, ergonovine...

Purified ergopeptine alkaloids are often used in studies related to tall fescue toxicosis without regard to epimerization that occurs when ergopeptines are solvated. The objectives of this study were to measure the rates of alpha-ergocryptine epimerization to alpha-ergocryptinine at room temperature and at -40 degrees C, and to measure the rate of ergovaline epimerization to ergovalinine at 37 ...