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Poppies (Papaver sp.). Poisoning by the two common poppies (P. Rhoeas L. and P. dubium L.) is not common, but Cornevin says that the former is poisonous in all its parts, and sufficiently so to cause accidents every year. Animals may be affected by eating the plant when mixed with green fodder, or by ingesting the seeds and capsules with waste material after the winnowing and grading of cereals. Stock, however, will most likely reject the plants, owing to their unpleasant odour and taste, but cattle have been poisoned by eating unripe heads of P. Rhoeas when the plant was mixed with clover and sainfoin. P. dubium has caused poisoning of horses, cattle and pigs.

Toxic Principle. Both species contain the alkaloids Morphine (C₁₇H₁₉NO₃) and Rheadine (C₂₁H₂₁NO₆), which are present in the milky juice of the plant. The latter, which was isolated by Hesse, is believed to have no narcotic effects. The toxic principle is not destroyed by heating, and the plant is therefore poisonous both in the green state and when dried in hay.

Symptoms. It is remarked by Cornevin that cattle poisoned by P. Rhoeas at first exhibit symptoms of excitement, shown by continual movement, by pawing of the soil or litter, increased respiration and more rapid pulse; this is followed by stoppage of the digestive functions, sometimes a little swelling of the eyelids, and coma, one affected animal appearing to sleep while standing, remaining motionless, and if forced to move walking in an unsteady manner. Finally, the animal falls, and if a fatal result is likely (which is unusual) it remains stretched on the ground; respiration becomes slower, the temperature falls, and after a few convulsive movements death occurs owing to asphyxia.

Müller notes excitement, wildness of look, dilatation of pupil, convulsions; then coma, loss of sensation and symptoms of depression replace those of excitement. There is salivation, bloating, constipation, and in many cases also bloody diarrhoea. Death, however, is rare.

Pott gives stupidity, retention of urine, colic, with sickness and diarrhœa, convulsions, and epileptic symptoms, the animals falling over and rolling.

REFERENCES.

4, 16, 63, 128, 190, 205, 213, 262.

Greater Celandine (Chelidonium majus L.). This common plant exhales an unpleasant odour, and when bruised or broken shows the presence of a yellowish acrid juice, which becomes red immediately on exposure to the air. It is an old medicinal drug plant, but is dangerous, being emetic and purgative, with a strongly irritating effect on the digestive tract. Animals are but rarely likely to take it, and no record of the death of domesticated animals has been found.

Toxic Principle. Among the substances contained in the Greater Celandine may be mentioned the bitter alkaloid Chelidonine (C₂₀H₁₉NO₅ + H₂O), which, especially occurring in the root, does not appear to be poisonous, or is of feeble activity; the alkaloid Chelerythrine (C₂₁H₁₇NO₄), which is poisonous; and Protopine (C₂₀H₁₉NO₅). It is stated by Cornevin that the toxic substance is not removed on drying, but Pott (1907) remarks that the dried plant is harmless to animals, the poisonous alkaloid being volatile and disappearing on drying.

Symptoms. The action of this plant is acrid, irritant and narcotic, emetic and purgative. Esser remarks that when Chelerythrine is introduced on the nasal mucous membrane it causes violent sneezing, and taken internally causes vomiting. Müller says that poisoning of domesticated animals is not recorded, but that according to old accounts 500 grammes (about 1 lb.) of the fresh plant eaten by the horse will at most cause slight diabetes.

REFERENCES.

16, 63, 81, 128, 141, 190, 203, 205, 213.