lasses--those that are likely to
be administered to the animal as medicine, and such as may be taken in the
feed, either in the shape of poisonous plants or as plants or feeds of
vegetable origin that have been damaged by fungi or by bacteria which have
produced fermentation or putrefaction.

VEGETABLE POISONS USED AS MEDICINE.

OPIUM (MORPHIN, LAUDANUM) POISONING.

Opium and its alkaloid, morphia, are so commonly used in the practice of
medicine that the poisonous result of an overdose is not uncommon. The
common preparations are gum opium, the inspissated juice of the poppy;
powdered opium, made from the gum; tincture of opium, commonly called
laudanum; and the alkaloid or active principle, morphia. Laudanum has about
one-eighth the strength of the gum or powder. Morphia is present in good
opium to the extent of about 10 per cent. In medicine it is a most useful
agent in allaying pain. It first produces a stimulating action, which is
followed by drowsiness, a disposition to sleep or complete anesthesia,
depending on the quantity of the drug used. In poisonous doses a state of
exhilaration is well marked at first. This is particularly noticeable in
cattle and in horses. The animal becomes much excited, and this stage does
not pass into insensibility unless an enormous dose has been given. If the
dose is large enough, a second stage sometimes supervenes, in which the
symptoms are those of congestion of the brain. The visible membranes have a
bluish tint (cyanotic) from interference with the air supply. The breathing
is slow, labored, and later stertorous; the pupils of the eyes are very
much contracted; the skin dry and warm. Gas accumulates in the stomach, so
that tympanites is a prominent symptom. The patient may be aroused by great
noise or the infliction of sharp pain, when the breathing becomes more
natural. A lapse into the comatose condition takes place when the
excitement ceases. Later, there is perfect coma and the patient can no
longer be aroused from the insensible condition. The contraction of the
pupil becomes more marked, the breathing intermittent and slower, there is
perspiration, the pulse more feeble and rapid, till death takes place.
Poisoning of cattle with opium or its products rarely goes beyond the stage
of excitement, because the quantity of the drug required for the later
effects is so great. Seventy-five grains of morphia administered
subcutaneously has sufficed merely to excite for 12 hours