Buxus sempervirens (dugeon). A genus of the plant family BUXACEAE. Evergreen shrub which will grow into a tree if not kept in a dwarfed state. Dense, dark green foliage; the leaves are small, ovate with a distinctive odour and an astringent taste. Flowers are bunched together, the fruit capsular, dehiscing explosively when mature. A popular ornamental shrub or hedging plant.


[affected.gif] Animals most affected
Cattle, (horses, sheep, pigs, dogs).


[etiology.gif] Etiology
Ingestion of the branches and leaves (either whilst growing or after hedge trimming). Poisoning is uncommon due to the extremely bitter taste of the plant, by may occur in periods of food shortage.


[toxic.gif] Toxicity
Contains the alkaloids: buxine, parabuxine, buxinidine, parabuinidine, buxinamine. The entire plant is toxic and the toxicity is not modified by drying.

Toxic doses are not well known.
LD horses 700 - 900 g leaves
  cattle 300 - 1000 g leaves



[clinical.gif] Clinical features
Gastrointestinal

Neurological


[lesions.gif] Lesions




[treatm~1.gif] Treatment
No antidote. Symptomatic care only:


[labinv~1.gif] Laboratory investigations
Poisoning may be confirmed by analysis of the contents of the rumen or stomach.


[case.gif] Case summaries
In a period of drought, a colleague was called to look at four cattle presenting with profuse diarrhoea, dehydration and minor difficulties with maintaining their balance. Despite symptomatic care, three of the animals had died by the following morning; the fourth animal recovered quickly. A search of the land revealed that the area had been sprayed with parathion (which was excluded as a cause by the analytical laboratory) and also the presence of several toxic plants (arum - not eaten; bryony - of which small quantities had been consumed).
After 3 weeks of being housed with no further complications noted, the herd was put into the same field. Five days later, one cow had digestive problems which resolved with treatment. However, 24 hours later, the animal developed neurological signs (dizziness, difficulties with balance, pharyngeal paralysis). Recovery took 4 days. A more careful search of the grazing area that the field was bordered by hedges contained box. Subsequent monitoring the animals showed that they were grazing off these plants.