Prevalence of ergot derivatives in natural ryegrass pastures: detection and pathogenicity in the horse.

In the present study, we determined the incidence and effects of season and weather on clinical manifestations of endophyte-infected ryegrass toxicity, performed chemical detection and pharmacological bioassays on ryegrass extracts, and conducted trials on: (i) effects of domperidone or metochlopramide on ovarian inactivity induced by endophyte-infected ryegrass; (ii) efficacy of buspirone or dihydrochloro phenyl piperazine (m-CPP) for preventing suppressed milk production induced by endophyte-infected ryegrass; and (iii) efficacy of domperidone to induce ovulation during winter anestrus. Mares with toxicosis had prolonged gestation, embryonic losses, dystocia, poor mammary gland development, low milk production, prolonged uterine involution, and suppressed ovarian activity. Foals had respiratory failure, abnormalities of the skin, umbilicus, bone, and muscle, failure to thrive, blindness, testicular atrophy, and decreased serum total immunoglobulin concentrations. Endophyte-infected ryegrass and the incidence of toxicosis were correlated (r=0.861, P=0.03). Ergot alkaloids were not detected in extracts of endophyte-infected ryegrass by either thin-layer chromatography or spectrophotometry, but their presence was inferred in bioassays of extracts (dose-related increases in the contractile response of rat uterus). Mares given metoclopropamide (0.6 mg/kg/d), given orally every 8h for up to 7d) ovulated earlier (4-7d vs. 15-18d, P<0.001) than those given domperidone (1.1mg/kg/d) orally for up to 18d). Although both metoclopropamide and domperidone induced milk production, the latter did not induce ovarian cyclicity in healthy mares during seasonal anestrus. Based on these findings, we inferred that endophyte-infected ryegrass is associated with ergot alkaloid intoxication in horse.

The obstetrical use in ancient and early modern times of Convolvulus scammonia or Scammony: another non-fungal source of ergot alkaloids?

PIP: This brief historical survey documenting the use of ergot alkaloids throughout Ancient times for obstetrical purposes (labor induction and control of uterine hemmorrhage) takes its data from works of Theophrastus (who wrote Enquiry into Plants around 300 B.C.), Pliny, Dioscorides, and others. What this history documents is another source for the ergot besides the fungus Clavicips purpurea; notations from Greek, Mexican, and English catalogers show that the family Convolvulaceae is a constant source of ergot alkaloids; this family is the home of Rivea corymbosa, the morning glory seed used by Mexican Indians for both medicinal and religious purposes. In addition, an argument made from salient quotations from historical texts indicates that Scammony may also contain ergot alkaloids, although such compounds have yet to be chemically isolated. Only 1 extant study intimates the possible existence of ergot-like activity in Scammony, a study which showed that small doses of an ether extract of Scammony resin stimulated an isolated guinea pig uterus. If Scammony does contain ergot alkaloids, it is suggested that it will be an excellent source for this material, since the plants cultivation is inexpensive and easy.^ieng