Entire-leaved groundsel-Senecio integerrimus Nutt.-Poisonous plant

Entire-leaved groundsel

General poisoning notes:

Entire-leaved groundsel (Senecio integerrimus) is a native herb found through parts of western Canada in the prairies, parklands, and parts of the Rocky Mountains. This plant has caused experimentally chronic poisoning of cattle and horses. Ingesting the plant material over long periods causes irreversible liver damage in animals. This plant grows when other forage is abundant so that it is not a a toxic threat unless forage is scarce or the plant is abundant in an area to be cut for hay (Clawson 1933).

Nomenclature:

Scientific Name: Senecio integerrimus Nutt.

Vernacular name(s): entire-leaved groundsel

Scientific family name: Compositae

Vernacular family name: composite.

Geographic Information

Alberta, British Columbia, Manitoba, Northwest Territories, Saskatchewan, Yukon Territory

Notes on Poisonous plant parts:

Ingesting the aboveground parts caused poisoning of cattle and horses in experiments. Two cows died after ingesting 92.3 and 135% of their body weight in green plants. A horse fed plants equal to 156% of its body weight (in 81 days) died. A horse fed 76% of its body weight (in 79 days) suffered liver damage. Sheep fed 4.5 kg of green plant material for 28 days showed no symptoms. Liver damage results from ingesting this plant material but takes a long time to develop (Clawson 1933).

Toxic parts:

All parts, flowers, leaves, stems

Notes on Toxic plant chemicals:

Pyrrolizidine alkaloids are found in other toxic members of the genus Senecio and are probably the chemicals responsible for cases of poisoning found in experiments.

Toxic plant chemicals:

unknown chemical

Animals/Human Poisoning:

Note: When an animal is listed without additional information, the literature (as of 1993) contained no detailed explanation.

Cattle

General symptoms of poisoning:

Death, depression, icterus, liver, cirrhosis of, restlessness, weakness, weight loss.

Notes on poisoning:

Experimental ingestion of plant material caused poisoning and death in cattle. Symptoms are similar to poisoning by other members of the genus Senecio, with liver damage causing many of the symptoms. Signs included depression, a peculiar sweet odor from the skin, yellowish discoloration of mucous membranes, itchiness, edema, serum oozing from the skin, and liver damage (Clawson 1933).

Horses

General symptoms of poisoning:

Confusion, death, depression, icterus, restlessness, weakness, weight loss.

Notes on poisoning:

Ingesting plant material caused a yellowish discoloration of mucous membranes, a sweet odor from the skin, depression, weakness, restless walking and, after 1 or 2 days, insensibility to objects and pushing against obstacles, urine discoloration, and death. All horses that showed definite symptoms died. Liver damage was apparent upon postmortem examination (Clawson 1933).