Colchicum autumnale (meadow saffron, autumn crocus, naked ladies). A member
of the plant family LILIACEAE. Perennial plant growing from a bulb or corm, from
which emerge long dark green leaves and green capsules in spring. In autumn pale
mauve or white tubular flowers appear, borne at the end of long stems.
Animals most affected
Cattle, sheep, occasionally horses and pigs.
Ingestion of the young leaves (in spring), fruit capsules or flowers (in autumn)
may result in poisoning. Consumption is usually minimal (or insignificant) but in
certain ill defined circumstances, massive ingestion of the plant has been reported.
Treatment with certain herbicides (e.g. phenoxyacids: 2,4-D and 2,4,5-T) renders
the plant more palatable and is likely to increase the incidence of poisoning.
Contains the alkaloids colchicine and colchiceine.
Both alkaloids withstand storage, drying and boiling. The seeds are highly toxic.
Toxic oral doses:
1 mg/kg for most animals
fresh plant material
8-10 g/kg in cattle
Note:intestinal absorption of colchicine is slow, delaying the onset of clinical
effects and the sequence of their presentation; the alkaloids may pass into milk,
albeit to a small degree; it is therefore advisable not to use the milk from affected
Delayed in their onset, appearing several
hours to 2 days post-ingestion.
Severe gastrointestinal effects
colic, abdominal pain, violent purgation
with the passage of foetid, white or dark green faeces;
acute rectal spasms, tenesmus.
apathy, restlessness, anxiety, progressing
ataxia, prostration, decubitus.
Various other clinical effects
bradypnoea, tachycardia, life4hreaten-mg
hypothermia, general collapse;
death may occur due to respiratory failure
within a few hours, or may be delayed for several (4-7) days.
Non-specific: pronounced gastroenteritis with severe congestion of the rumen, the
small intestine, occasionally exhibiting
erosions of the mucosae, ulceration and haemorrhages.
No antidote. Symptomatic care only:
adsorbents (activated vegetable charcoal);
intestinal demulcents and antiseptics;
calcium gluconate, iv hypertonic glucose
A group of cows and sheep were put out to
graze in the grounds (approximately 100 hectares) of a large country house. The animals
were left unsupervised for several days; when the farmer returned to check his stock,
he found that two of his cows had died and a third had severe dysentery and was badly
dehydrated, with sunken eyes.
Enquiries revealed that the field had been
sprayed earlier in the season with 2,4-D. In addition, numerous toxic plants were
found growing in the same area. Analysis of the ruminal contents of one of the dead
cows revealed fruit capsules of colchicum (however only a few whole capsules were
visible as they were mostly reduced to pulp). 2,4-D poisoning is different in its
presentation. It is a compound of low toxicity, causing different clinical features
and, in this case, the amount sprayed was not toxicologically significant. However
the use of the agrochemical had definitely influenced the incidence of poisoning
by increasing the palatability of colchicum, a plant which is normally ignored or
avoided by grazing animals.