Toxigenic Endophyte-Infected Tall Fescue and Ergot Alkaloids

Vet Clin North Am Equine Pract. 2024 Apr;40(1):95-111. doi: 10.1016/j.cveq.2024.01.001. Epub 2024 Jan 27.

Abstract

"Fescue toxicosis" and reproductive ergotism present identical toxidromes in late-gestational mares and, likely, other equids. Both toxic syndromes are caused by ergopeptine alkaloids (EPAs) of fungal origin, and they are collectively referred to as equine ergopeptine alkaloid toxicosis (EEPAT). EPAs are produced by either a toxigenic endophyte (Epichloë coenophiala) in tall fescue and/or a nonendophytic fungus (Claviceps purpurea), infecting small grains and grasses. EEPAT can cause hypoprolactinemia-induced agalactia/dysgalactia, prolonged gestation, dystocia, and other reproductive abnormalities in mares, as well as failure of passive transfer in their frequently dysmature/overmature/postmature foals. Prevention relies on eliminating exposures and/or reversing hypoprolactinemia.

Keywords: Agalactia; Dysgalactia; Dystocia; Ergopeptine alkaloids; Ergot; Ergot alkaloids; Ergotism; Fescue toxicosis.

Publication types

  • Review

MeSH terms

  • Animals
  • Endophytes
  • Ergot Alkaloids* / toxicity
  • Female
  • Festuca* / microbiology
  • Horse Diseases* / chemically induced
  • Horses
  • Poaceae
  • Pregnancy

Substances

  • Ergot Alkaloids