Hellebores (Helleborus sp.). Two poisonous species of hellebore may on occasion be taken by live stock, though rarely—Stinking Hellebore (H. fœtidus L.) and Green Hellebore (H. viridis L.). The much esteemed Christmas Rose (H. niger) is also toxic, but unlikely to be eaten by stock. In no case should trimmings of these plants from shrubberies, etc., be thrown to stock—cows have died from eating such trimmings. The two species first mentioned are equally toxic, all parts are poisonous, and drying does not render them innocuous. Cornevin records that animals have been killed by H. fœtidus, and says that 9½ oz. of the fresh root or 2½ oz. of the dried root are poisonous doses to the horse, while 120 to 150 grains are fatal to sheep. It was recorded in 1847 (Veterinarian) by Mayer that a horse was fatally poisoned through eating five half-pints of the chopped-up leaves of this species in two days in a bran mash. In regard to this species also Johnson and Sowerby write: “The Bear’s-Foot has been used as a vermifuge ever since the days of Hippocrates, notwithstanding its dangerous qualities. Every part of the plant is a violent cathartic, but far too uncertain in the degree of its action to be safely administered.”
Toxic Principle. Both species contain the poisonous glucosides Helleborin (C36H42O6), a highly narcotic and powerful poison; Helleborein (C26H44O15); and the alkaloid Jervine (C26H37O3N2H2O).
Symptoms. The Hellebores are cathartic, narcotic, and drastically purgative. Stupor is followed by death with spasms in the case of H. viridis (Pammel). In general there is in the horse and ox bloody purgation, salivation, attempts to vomit, and excessive urination, according to Lander, who cites Mayer as noting violent straining and the discharge of frothy mucus, but no effort to vomit, the heart action resembling that observed in Digitalis poisoning, showing periodic intervals of arrest in systole.
Müller gives the symptoms in cattle and sheep after eating the leaves as loss of appetite, nausea, and even vomiting, salivation, grinding of teeth, wind, colic, bloody diarrhœa, decrepitude, giddiness, loss of sensation, convulsions, and not seldom death.
Affected cows are stated to give bitter milk which has purgative effects (Pott).
The poisoning of two cows by H. viridis came under the notice of Cornevin. There was observed loss of appetite, diarrhœa, tenesmus, violent attempts to evacuate, which after 5 or 6 days resulted only in the expulsion of glareous blackish matter; to the end the pulse was slow and intermittent. The heart beats were weak, and after 5 or 6 beats there was a stop equal in duration to at least a beat and a half. A remarkable fact was the very gradual loss of condition, while the milk secretion was maintained until the last day. In one case death occurred after 12 days and in the other after 28 days.
REFERENCES.
[63], [81], [130], [140], [170], [190], [203], [205], [213], [233], [254].
Larkspur (Delphinium Ajacis Reich.). In the United States of America certain species of Larkspur are exceedingly harmful to live stock, and it has been said that “with the exception of the Loco weeds there is probably no poisonous plant on the cattle ranges of the West that has caused such heavy losses to stockmen as has larkspur” (Far. Bul. 53, U. S. Dept. Agric.). D. Ajacis is the only British species, occurring in cornfields in Cambridgeshire, Sussex and elsewhere, and, like the Continental species D. Consolida, must be regarded as poisonous and fatal to cattle, while horses and sheep may also suffer. Sheep and goats, however, appear to resist the poison unless taken in considerable quantity. Wilcox fatally poisoned a yearling lamb within an hour of administering per os the extract from less than 1 oz. of the dried leaves of an American species. The seeds are the most dangerous part of the Larkspur, and should never be ground up with wheat should the two plants grow together. The seeds of D. Staphisagria are used in medicine.
Toxic Principle. The species D. Ajacis has been little studied, but D. Consolida and D. Staphisagria contain the alkaloids Delphinine (C31H49O7N), very poisonous and having a bitter taste; Delphisine (C31H49O7N), which is extremely poisonous; Delphinoidine (C42H68N2O7), which is poisonous; and Staphisagrine.