The treatment of animals suffering from poison must vary according to the nature of the toxic agent. There are a few general plans of action, however, which should be followed so far as possible. In man and in some of the smaller animals it is possible to eliminate unabsorbed poison by the use of the stomach pump or by causing vomiting. These proceedings are impracticable in cattle. It is well, therefore, in many cases to endeavor to expel the unabsorbed poison by emptying the digestive tract, so far as may be, with a nonirritating purge. Castor oil in doses of 1 pint to 2 quarts is adapted to this purpose. If the poison is known to be nonirritant—as a narcotic plant—from 10 to 20 drops of croton oil may be given with a quart of castor oil. When poisons are somewhat prolonged in their effect, Epsom salt in doses of 1 pound can be given advantageously. To protect the mucous membrane from the action of strong irritants, one may give flaxseed tea, barley water, the whites of eggs, milk, butter, olive oil, or fresh lard. Chemical antidotes may sometimes be used for special poisons, as advised below. In general, if an acid has been taken it may be neutralized with an alkali, such as chalk, magnesia, bicarbonate of soda (baking soda), ammonia (diluted), or soap. If the poison is an alkali, such as caustic soda or potash (lye), or ammonia, an acid, such as diluted (1 per cent) sulphuric acid or vinegar, may be administered. Special treatments and antidotes are considered below.
A poisonous agent may be so gradually introduced into the system as to slowly develop the power of resistance against its own action. In other cases where the poison is introduced slowly the poisonous action becomes accumulative, and, although there is no increase in the quantity taken, violent symptoms are suddenly developed, as if the whole amount, the consumption of which may have extended over a considerable period, had been given in one dose. Other agents, poisonous in their nature, tend to deteriorate some of the important organs, and, interfering with their natural functions, are productive of conditions of ill health which, although not necessarily fatal, are important. Such might properly be called chronic poisons. Poisons of themselves dangerous when administered in large doses are used medicinally for curative purposes, and a very large percentage of the pharmaceutical preparations used in the practice of medicine if given in excessive quantities may produce serious results. In the administration of medicines, therefore, care should be exercised not only that the animal is not poisoned by the administration of an excessive dose but that injury is not done by continued treatment with medicines the administration of which is not called for.
MINERAL POISONS.
ARSENIC POISONING.
Of the common irritant and corrosive poisons, arsenic, especially one of its compounds (Paris green), is likely to be the most dangerous to our class of patients. The common practice of using Paris green and other compounds of arsenic as insecticides for the destruction of potato beetle and other insect enemies of the farmer and fruit grower has had the effect of introducing it into almost all farming establishments. White arsenic is also a principal ingredient in some popular dipping preparations, and poisoning from this source occasionally takes place when, after dipping, animals are allowed to run in a yard in which there is loose fodder. The drippings from the animals falling on the fodder render it poisonous and dangerous to animal life if eaten. Familiarity with its use has in many instances tended to breed contempt for its potency as a poison. Rat poisons often contain arsenic. The excessive use of arsenic as a tonic, or of "condition powders" containing arsenic, has been the means of poisoning many animals. This is the common poison used by malicious persons with criminal intent. The poison may also be absorbed through wounds or through the skin if used as a dip or bath.
If a large dose is given, at once acute poisoning is produced; if repeated small doses are given, chronic poisoning may result. The poisonous dose for an ox is from 3 drams to 1 ounce.
Symptoms.—The symptoms of acute poisoning first appear as those of colic; the animal is restless, stamping with the feet, lying down and getting up. There is tenderness on pressure over the abdomen. The acute symptoms increase; in a few hours violent diarrhea is developed; in many cases blood and shreds of detached mucous membrane are mixed with the evacuations. There is irregular and feeble pulse and respiration, and death is likely to supervene between the eighteenth hour and the third day. If the latter period is passed, there is a reasonable hope of recovery.
In chronic poisoning the symptoms are similar to those of chronic gastrointestinal catarrh, with indigestion, diarrhea, and general weakness and loss of condition.
Treatment.—The antidote for arsenic is a solution of hydrated oxid of iron in water. It should be prepared fresh by mixing a solution of sulphate of iron, made by dissolving 4 ounces of sulphate of iron in one-half pint water, with a suspension of 1 ounce of magnesia in one-half pint water. This quantity is sufficient for one dose for a cow and may be repeated in an hour, if much arsenic was taken. A solution of calcined magnesia or powdered iron or iron filings or iron scale from a blacksmith's forge may be given in the absence of other remedies. Powdered sulphur is of some value as an antidote. One must also administer protectives, such as linseed tea, barley water, whites of eggs, etc.