Ergot Claviceps Claviceps spp

Ergot
Claviceps
Claviceps spp.
FAMILY: Ascomycetes

OCCURRENCE:
Claviceps parasitizes the ovary of grasses, especially rye, wheat (durum is most susceptible), barley, and some wild species. Infection occurs when host flowers begin to open.

DISTRIBUTION:
Ergot occurs on pasture land grasses or hay and cereal grains from cultivated fields.

TOXIC PARTS:
The poisonous part is the sclerotium (ergot body), a grain-shaped mass that replaces the grass ovary. This varies in size from the same as the grain to 4 times larger. The fungal mass, homogeneous and white when cut open, is shed with the grass and acts as the overwintering phase of the fungus. Federal law prohibits use of cereal grains containing more than 0.3% sclerotia by weight.

TOXICITY:
Two syndromes are produced by ingestion: 1) gangrenous, and 2) convulsive. Ingestion of small amounts daily over a short period results in necrosis of tissues in the extremities, producing dry gangrene. Gangrene is caused by constriction of the blood vessels with blockage of circulation. This results in lameness, coldness, and insensitivity to pain of the affected part. In some instances, serum seepage can cause secondary infection, which may be associated with nausea, vomiting, abdominal pain. and constipation or diarrhea. Pregnant animals spontaneously abort. Mucus membranes of the oral cavity may be inflamed or damaged. In humans gastrointestinal distress and headache may be present. Fowl may lose their combs and beaks. Convulsive ergotism results from ingestion of large quantities of ergot. In addition to the above syndrome, nervous symptoms appear, which are characterized by hyperexcitability, paranoia, rapid pulse, and belligerence. In livestock, death may result from dehydration or starvation within a few days or a month. In humans, whole body spasms and delirium may be present,.

TOXIC PRINCIPLES:
Alkaloids, amines, and other organic compounds are present in ergot. The antihemorrhagic alkaloids probably are the major problem. Chemical formulas are known for two dozen alkaloids, derivatives of lysergic acid. Compounds include ergocryptine, ergocornine, ergocristine, ergotamine, ergosine, and ergonovine.

TREATMENT: Gastric lavage, emesis ; treat symptoms asw they appear, supportive therapy.