Part 17

In recent years tincture of aconite has become a popular stable remedy. If an animal is ailing, aconite is given whether indicated or not. Fortunately the dose used is generally small, and for this reason the damage done is much less than it would otherwise be. Aconite is one of the most deadly poisons known. It produces paralysis of motion and sensation, depresses the heart's action, and causes death by paralysis of respiration. In large doses it causes profuse salivation, champing of the jaws, and attempts at swallowing. If not sufficient to cause death, there is impaired appetite with more or less nausea for some time after. In poisonous doses it causes the animal to tremble violently, to lose power to support itself, and brings on slight convulsions, with perspiration. The pulse is depressed, irregular, and afterwards intermittent.

Treatment.--The chemical antidote is tannic acid, which forms an insoluble compound with the aconitin. The depressing effect on the heart should be counteracted by the use of ammonia, digitalis, alcohol, camphor, or other diffusible stimulants, which have a physiological effect opposite to aconite.

POISONOUS PLANTS.

An important group of poisons may be classed under this head. In most cases it is poison naturally belonging in the plant; in other cases the poisonous principle is developed in what would otherwise be harmless plants as a plant disease, or as a fermentation or putrefaction due to bacterial growth and observed in forage, grain, or meal that has become heated, damaged, or "spoilt."

The subject of poisonous plants is an important one and is of especial interest to those using the western stock ranges, for it is probable that there is no other single cause producing so many fatalities. In this article only a few of the more important plants are treated in a brief way, for an extended treatise would be necessary if the subject were to be handled adequately. Further information should be sought in the more elaborate publications. Many of the American poisonous plants have been treated in bulletins issued by the United States Department of Agriculture.

Treatment for plant poisoning.--Remedies given by the mouth in most cases fail to give relief to cattle affected by poisonous plants. The material of the poisonous plants in the first stomach is not very largely affected by a remedy given as a drench. If any beneficial result is effected, it must be on the material which has already passed into the fourth stomach, so that to get any real antidotal result the remedy must be given repeatedly in order to meet the alkaloid poisons as they are passing through the fourth stomach. While certain substances like tannic acid and potassium permanganate are the logical antidotes for plant poisons, in practical application they are very disappointing in the treatment of ruminant animals. Reliance must be mainly on prevention and upon such remedies as will increase elimination. A laxative or purgative is always helpful, and for this purpose Epsom salt may be given in pound doses, or linseed oil in doses of 1 or 2 pints. In some few cases special remedies can be given as is indicated below.

It is well to bear in mind that cattle while grazing freely in good pasture are not likely to eat poisonous plants to any extent. If these same plants are gathered and thrown in a pile, the animals, through a kind of pernicious curiosity, may eat them with disastrous results. This has frequently happened when freshly cut branches of cherry, yew, oleander, and other plants have been thrown where dairy cattle could get at them.

OAKS.

The foliage of oaks is a valuable constituent of the forage on many ranges and pastures. It has been shown, however, that when this is eaten without some admixture of other food, cattle frequently sicken and die. Many cases of the poisoning of cattle by acorns have been reported in England and Germany, and there have been some complaints in the United States. Harmful results from eating acorns do not seem likely to occur except as they are eaten in considerable quantities.

Symptoms.--The symptoms of oak poisoning are constipation, mucus and blood in the feces, emaciation, and edema. The symptoms of acorn poisoning are much the same.

Treatment.--Change of pasture or an addition of other food material.

HORSE CHESTNUT--BUCKEYE.

All the species of ∆sculus, popularly known as horse chestnut or buckeye, are considered poisonous. The bark, leaves, and fruit are injurious. It is said that if the fruit is boiled or roasted and washed out it becomes harmless and even is a desirable addition to the feed of cattle. The Indians in time of scarcity of food have used the fruit after preparing it in this way. The buckeyes are said to have a specific effect in producing abortion in cattle and goats.

DEATH CAMAS (SPECIES OF ZYGADENUS).

The death-camas plants, which are commonly known in the Pacific States as "lobelia," are especially destructive of sheep, but cattle sometimes eat them and are poisoned. Cases of cattle poisoning are not likely to result fatally.

Symptoms.--The symptoms are salivation, nausea accompanied by vomiting, great weakness, and lowered temperature.

Treatment.--There is no effective treatment for death-camas poisoning.

FLY POISON (CHROSPERMA MUSC∆TORIUM).

This plant, which is closely related to the death-camas plants, is sometimes known as "stagger grass" and causes a considerable loss in the Southern States. It grows earlier than the grasses, and on this account is more likely to be eaten. Like death camas, it produces pronounced nausea, resulting in vomiting and weakness, and in cases which recover the effects may continue for several days. Apparently the injurious effects are more common in the case of cattle than in other domestic animals. There is no known way of treating these animals, though doubtless purgatives would be beneficial.

YEW (TAXUS BACCATA).

The European yew has long been known as a very poisonous plant. It is cultivated in America, and while cases of poisoning have not been common, it is well to recognize its dangerous character. A comparatively small dose is poisonous and ordinarily acts with great rapidity. It causes respiratory paralysis and the animal dies in convulsions.

LAUREL.

The laurels, including the broad-leafed laurel, Kalmia latifolia, the narrow-leafed laurel, Kalmia angustifolia, the rhododendrons, and other closely related plants are poisonous and cause considerable losses. It is dangerous to let cattle graze where these plants are abundant at times when other forage is scarce. The symptoms are salivation, nausea and vomiting, spasms, dizziness, stupor, and death.

FERN.

The common brake or bracken fern, Pteris aquilina, has been considered responsible for the poisoning of many horses and cattle. Many cases have been reported in England and Germany, and some well-authenticated cases in the United States. Very little has been learned experimentally of fern poisoning, but there seems to be little question that it has been the cause of many deaths. The symptoms are said to be temperature higher than normal, loss of appetite, bloody discharges from mouth, nose, and bowels, and great depression followed by coma and death. Some authors say that the urine is colored by blood. It is thought by some that the disease known as "red water" in the northwestern United States and Canada is caused by eating ferns.

SORGHUM POISONING.

Under certain conditions sorghum contains enough hydrocyanic acid to make it exceedingly dangerous to cattle. These cases of poisoning most commonly occur when cattle are pastured upon the young plant or upon a field where the crop has been cut and is making a second growth. Conditions of drought make the sorghum especially dangerous. There is some reason to think that the frosted second growth is particularly rich in hydrocyanic acid. The cases of poisoning occur when animals are grazed upon the plant, but not from the harvested crop or from silage. If cattle are grazed on sorghum or sorghum stubble they should at first be under constant observation and should be removed as soon as any signs of illness appear. Similar precautions should be used in grazing kafir.

CORNSTALK DISEASE.