Part 16

The carbonates of potash and soda and the alkalies themselves in concentrated form cause symptoms of intestinal irritation similar to those produced by mineral acids. Ammonia, caustic soda, and caustic potash (lye) are those to which animals are most exposed. The degree of their caustic irritant effects depends on their degree of concentration. When they reach the stomach the symptoms are nearly as well marked as in the case of the acids. The irritation is even more noticeable, and purgation is likely to be a more prominent symptom. If death is not caused soon, the irritation of the gastrointestinal tract and malnutrition will last for a long time.

Treatment.--Treatment consists in neutralizing the alkali by an acid, such as dilute sulphuric acid (1 per cent) or strong vinegar. The administration of such an antidote and its action must be carefully watched during administration. In the chemical change which takes place when the acid and alkali are combined, carbonic-acid gas is liberated, which may be to an extent sufficient to cause considerable distention of the abdomen, and even to produce asphyxia from pressure forward on the diaphragm. Should this danger present itself, it may be averted by opening the flank, permitting the gas to escape. (See "Acute tympanites, or Bloating," p. 22.) Flaxseed or slippery-elm decoction must be given to sooth the inflamed mucous surface. Opium may be used to allay pain.

COAL-OIL POISONING.

Coal oil is sometimes administered empirically as a treatment for intestinal parasites. If given in large doses it produces poisonous effects, which are likely to be manifested some time after the administration. It acts as an irritant to the digestive tract, causing dribbling of ropy saliva from the mouth, diarrhea, tenesmus, and loss of appetite, with increased temperature and cold extremities. Visible mucous membranes are injected, pupils of the eyes are contracted, and there is a watery discharge from the eyes and nostrils. Remotely it exerts a depressing influence on the functions of the brain and slight coma, and occasionally convulsions, from which the animal is easily aroused. The kidneys also suffer. The urine is dark colored and has the characteristic odor of coal oil. Death may result from gastroenteritis or convulsions.

Treatment.--The patient's strength should be fostered by the frequent administration of mild stimulants, of which aromatic spirits of ammonia is perhaps the best. The animal should be encouraged to eat soft feed and given mucilaginous drinks.

Crude coal oil is sometimes applied to the skin to kill parasites. If too much is used, especially in hot weather, great weakness and depression may be caused and in some cases death may result.

CARBOLIC-ACID POISONING.

Although one of the most valuable antiseptic remedies, carbolic acid in a concentrated form, when taken internally or used over a large surface externally, is likely to produce poisonous effects. It causes whitening, shrinking, and numbness of the structures with which it comes in contact, and, besides its irritant effect, exerts a powerful influence on the nervous system. Being readily absorbed, it produces its effect whether swallowed, injected into the rectum, inhaled, or applied to wounds, or even to a large tract of unbroken skin. Used extensively as a dressing, it may produce nausea, dizziness, and smoky or blackish colored urine. The last symptom is nearly always noticeable where the poisonous effect is produced. In more concentrated form, or used in larger quantities, convulsions, followed by fatal coma, are likely to take place. Even in smaller quantities, dullness, trembling, and disinclination for food often continue for several days. In a tolerably concentrated solution it coagulates albumen and acts as an astringent.

Treatment.--As an antidote internally, a solution of sulphate of soda or sulphate of magnesia (Glauber's or Epsom salt) may be given. The white of egg is also useful. Stimulants may be given if needed. When the poisoning occurs through too extensive applications to wounds or the skin, as in treatment of mange, cold water should be freely applied so as to wash off any of the acid that may still remain unabsorbed. As a surgical dressing a 3 per cent solution is strong enough for ordinary purposes. Water will not hold more than 5 per cent in permanent solution. No preparation stronger than the saturated solution should be used medicinally under any circumstances.

SALTPETER POISONING.

Both nitrate of soda and nitrate of potassium are poisonous to cattle. These substances are used for manure and for preserving meats. They may be administered in a drench by error in place of Glauber's salt, or they may be exposed within reach of cattle and thus be eaten. The toxic dose depends upon the condition of fullness of the stomach. If in solution and given on an empty stomach, as little as 3 ounces of saltpeter (nitrate of potassium) may be fatal to a cow. More of the Chile saltpeter (nitrate of soda) is required to cause serious trouble.

Symptoms.--Severe gastroenteritis, colic, tympanites, diarrhea, excessive urination, weakness, trembling, convulsions, collapse.

Treatment.--Same as for poisoning by common salt.

POISONING BY COMMON SALT.

A few pounds (3 to 5) of common salt will produce well-marked signs of poisoning in cattle. So much salt as this will not be taken by cattle except under unusual conditions. If the feed is poor in salt, and if no salt has been given for a long time, an intense "salt hunger" may occur that may lead an animal to eat a poisonous quantity, or an overdose of salt may be given by error as a drench. In order to prevent overeating of salt, it is doubtless better in salting cattle to use rock salt rather than that in more or less finely divided form.

Herring and mackerel brine and pork pickle are also poisonous, and are especially dangerous for hogs. In these substances there are, in addition to salt, certain products extracted from the fish or meat which undergo change and add to the toxicity of the solution. Sometimes saltpeter is present in such brines.

Symptoms.--The symptoms are great thirst, abdominal pain, diarrhea, poor appetite, redness and dryness of the mouth, increased urination, paralysis of the hind legs, weak pulse, general paralysis, coma, and death in from six to eight hours.

Treatment.--Allow as much warm water as the animal will drink; give protectives, such as linseed tea, etc. Linseed or olive oil may be given. To keep up the heart action give ether, alcohol, camphor, digitalis, or coffee. To allay pain, give opium.

VEGETABLE POISONS.

Vegetable poisons may be divided into two classes--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.

Treatment.--Give strong coffee, 1 to 4 quarts, aromatic spirits of ammonia or carbonate of ammonia. Atropia is the physiological antidote.

STRYCHNIN POISONING.

Strychnin is a very concentrated poison and produces its effect very quickly, usually only a few minutes being necessary if given in sufficient dose and in such a way that it will be at once absorbed. When employed as a medicine, as a rule, minimum doses should be used, as cattle are quite susceptible to its effects and may be killed by the maximum doses given in the common manuals of veterinary medicine. The first noticeable symptom is evidence of unrest or mental excitement; at the same time the muscles over the shoulder and croup may be seen to quiver or twitch, and later there occurs a more or less well-marked convulsion; the head is jerked back, the back arched and leg extended, the eyes drawn. The spasm continues for only a few minutes, when it relaxes and another occurs in a short time. The return is hastened by excitement and in a short time again disappears, continuing to disappear and reappear until death results. As the poisonous effect advances the intervals between the spasms become shorter and less marked and the spasms more severe until the animal dies in violent struggles.

Treatment.--The best method is to put the patient under the influence of chloral, chloroform, or ether, and keep it there continuously until the effect of the poison has passed off. Alcohol may be given in large doses.

ACONITE POISONING.