PLEURO-PNEUMONIA.

As very little is, at present, known of the nature of this disease, we give the reader the views of Mr. Dun, who received the gold medal offered by the Agricultural Society for the best essay on this subject.

"The causes of the disease, both immediate and remote, are subjects full of interest and importance; and a knowledge of them not only aids in the prevention of disease, but also leads the practitioner to form a more correct prognosis, and to pursue the most approved course of treatment. It is, however, unfortunate that the causes of pleuro-pneumonia have not as yet been satisfactorily explained. No department of the history of the disease is less understood, or more involved in doubt and obscurity. But in this respect pleuro-pneumonia is not peculiar: it is but one of an extensive class which embraces most epidemic and epizoötic diseases. And if the causes which produce influenza, fevers, and cholera, were clearly explained, those which produce pleuro-pneumonia would, in all probability, be easy of solution.

"Viewing the wide-spread and similar effects of pleuro-pneumonia, we may surmise that they are referable to some common cause. And although much difference of opinion exists upon this subject, it cannot be denied that contagion is a most active cause in the diffusion of the disease. Indeed, a due consideration of the history and spread of pleuro-pneumonia over all parts of the land will be sufficient to show that, in certain stages of the disease, it possesses the power of infecting animals apparently in a sound and healthy condition, and otherwise unexposed to the action of any exciting cause. The peculiarity of the progress of this disease, from the time that it first appeared in England, is of itself no small evidence of its contagious nature. Its slow and gradual progress is eminently characteristic of diffusion by contagion; and not only were the earlier cases which occurred in this island distinctly proved to have arisen from contact with the Irish droves, but also subsequent cases, even up to the present day, show numerous examples in which contagion is clearly and unequivocally traceable.... Although pleuro-pneumonia is not produced by the action of anyone of these circumstances alone, [referring to noxious effluvia, &c.,] yet many of them must be considered as predisposing to the disease; and although not its immediate exciting causes, yet, by depressing the physical powers, they render the system more liable to disease, and less able to withstand its assaults. Deficient ventilation, filth, insufficient and bad food, may indeed predispose to the disease, concentrate the animal effluvia, and become the matrix and nidus of the organic poison; but still, not one, alone, of these circumstances, or even all of them combined, can produce the disease in question. There must be the subtle poison to call them into operation, the specific influence to generate the disease."

"On the other hand, it appears probable that the exciting cause, whether it be contagion, or whatever else, cannot, of itself, generate the disease; but that certain conditions or predisposing causes are necessary to its existence, and without which its specific effects cannot be produced. But although these remote or predisposing causes are very numerous, they are often difficult of detection; nay, it is sometimes impossible to tell to what the disease is referable, or upon what weak point the exciting cause has fixed itself. A source of perplexity results from the fact.... The predisposing causes of the disease admit of many divisions and subdivisions; they may, however, be considered under two general heads—hereditary and acquired.

"With reference to the former, we know that good points and properties of an animal are transmitted from one generation to another; so also are faults, and the tendencies to particular diseases. As in the same families there is a similarity of external form, so is there also an internal likeness, which accounts for the common nature of their constitution, modified, however, by difference of age, sex, &c.

"Among the acquired predisposing causes of pleuro-pneumonia may be enumerated general debility, local weakness, resulting from previous disease, irritants and stimulants, exposure to cold, damp or sudden changes of temperature, the want of cleanliness, the breathing of an atmosphere vitiated by the decomposition of animal or vegetable matters, or laden with any other impurity. In short, under this head may be included every thing which tends to lower the health and vigor of the system, and consequently to increase the susceptibility to disease.

"The primary symptoms of pleuro-pneumonia are generally obscure, and too often excite but little attention or anxiety. As the disease steals on, the animal becomes dull and dejected, and, if in the field, separates itself from its fellows. It becomes uneasy, ceases to ruminate, and the respirations are a little hurried. If it be a milk-cow, the lacteal secretion is diminished, and the udder is hot and tender. The eyes are dull, the head is lowered, nose protruded, and the nostrils expanded. The urine generally becomes scanty and high-colored. It is seldom thought that much is the matter with the animal until it ceases to eat; but this criterion does not hold good in most cases of the disease, for the animal at the outset still takes its food, and continues to do so until the blood becomes impoverished and poisoned; it is then that the system becomes deranged, the digestive process impaired, and fever established. The skin adheres to the ribs, and there is tenderness along the spine. Manipulation of the trachea, and percussion applied to the sides, causes the animal to evince pain. Although the beast may have been ill only three days, the number of pulsations are generally about seventy per minute; but they are sometimes eighty, and even more. In the first stage, the artery under the jaw feels full and large; but as the disease runs on, the pulse rapidly becomes smaller, quicker, and more oppressed. The breathing is labored, and goes on accelerating as the local inflammation increases. The fore extremities are planted wide apart, with the elbows turned out in order to arch the ribs, and form fixed points for the action of those muscles which the animal brings into operation to assist the respiratory process. In pleuro-pneumonia, the hot stage of fever is never of long duration, [simply because there is not enough vitality in the system to keep up a continued fever.] The state of collapse quickly ensues, when the surface heat again decreases, and the pulse becomes small and less distinct. We have now that low typhoid fever so much to be dreaded, and which characterizes the disease in common with epizoötics.

" ... The horse laboring under pleuro-pneumonia, or, indeed, any pulmonary disease, will not lie down; but, in the same circumstances, cattle do so as readily as in health. They do not, however, lie upon their side, but couch upon the sternum, which is broad and flat, and covered by a quantity of fibro-cellular substance, which serves as a cushion; while the articulation between the lower extremities of the ribs admits of lateral expansion of the chest. In this position cattle generally lie towards the side principally affected, thus relieving the sounder side, and enabling it to act more freely. There is sometimes a shivering and general tremor, which may exist throughout the whole course of the disease. (This is owing to a loss of equilibrium between the nerves of nutrition and the circulation.) ... As the case advances in severity, and runs on to an unfavorable termination, the pulse loses its strength and becomes quicker. Respiration is in most cases attended by a grunt at the commencement of expiration—a symptom, however, not observable in the horse. The expired air is cold, and of a noisome odor. The animal crouches. There is sometimes an apparent knuckling over at the fetlocks, caused by pain in the joints. This symptom is mostly observable in cases when the pleura and pericardium are affected. The animal grinds its teeth. The appetite has now entirely failed, and the emaciation becomes extreme. The muscles, especially those employed in respiration, become wasted; the belly is tucked, and the flanks heave; the oppressive uneasiness is excessive; the strength fails, under the convulsive efforts attendant upon respiration, and the poor animal dies.

"In using means to prevent the occurrence of the disease, we should endeavor to maintain in a sound and healthy tone the physical powers of the stock, and to avoid whatever tends to depress the vital force. Exposure to the influence of contagion [and infection] must be guarded against, and, on the appearance of the disease, every precaution must be used to prevent the healthy having communication with the sick. By a steady pursuance, on the part of the stock proprietor, of these precautionary measures, and by the exercise of care, prudence, and attention, the virulence of the disease will, we are sure, be much abated, and its progress checked."

As the reader could not be benefited by our detailing the system of medication pursued in England,—at least we should judge not, when we take into consideration the great loss that attends their best efforts,—we shall therefore proceed to inform the reader what the treatment ought to be in the different stages of the disease.

General Indication of Cure in Pleuro-Pneumonia.—Restore the suppressed evacuations, or the secretions and excretions, if they are obstructed.

If bronchial irritation or a cough be present, shield and defend the mucous surfaces from irritation. Relieve congestions by equalizing the circulation. Support the powers of the system. Relieve all urgent symptoms.

Special Practice.—Suppose a cow to be attacked with a slight cough. She appears dull, and is off her feed; pulse full, and bowels constipated; and she is evidently out of condition.

Then the medicines should be anti-spasmodic and relaxant, tonic, diaphoretic, and lubricating.

The following is a good example:—

Powdered golden seal, (tonic,)1 table-spoonful.
Powdered mandrake, (relaxant,)2 tea-spoonfuls.
Powdered lobelia, (anti-spasmodic,)1 tea-spoonful.
Powdered slippery elm or mallows, (lubricating,)1 table-spoonful.
Powdered hyssop tea, (diaphoretic,)1 gallon.

After straining the hyssop tea, mix with it the other ingredients, and give a quart every two hours.

In the mean time, administer the following injection:—

Powdered lobelia,1/2 table-spoonful.
Powdered ginger,1/2 table-spoonful.
Boiling water,1 gallon.

When cool, inject.

Particular attention must be paid to the general surface, If the surface and the extremities are cold, then employ friction, warmth, and moisture. The animal must be in a comfortable barn, neither too hot nor too cold; if it be imperfectly ventilated, the atmosphere may be improved by stirring a red-hot iron in vinegar or pyroligneous acid, or by pouring either of these articles on heated bricks. The strength is to be supported, provided the animal be in poor condition, with gruel, made of flour and shorts, equal parts; but, as it frequently happens (in this country) that animals in good flesh are attacked, in such case food would be inadmissible.

Suppose the animal to have been at pasture, and she is not observed to be "ailing" until rumination is suspended. She then droops her head, and has a cough, accompanied with difficult breathing, weakness in the legs, and sore throat. Then, in addition to warmth, moisture, and friction, as already directed, apply to the joints and throat the following:

Boiling vinegar,1 quart.
African cayenne,1 table-spoonful.

The throat being sore, the part should be rubbed gently. The joints may be rubbed with energy for several minutes. The liquid must not be applied too hot.

Take
Virginia snakeroot,2 ounces.
Sage,2 ounces.
Skullcap, (herb),1 ounce.
Pleurisy root,1 ounce.
Infuse in boiling water,1 gallon.

After standing for the space of one hour, strain; then add a gill of honey and an ounce of powdered licorice or slippery elm. Give a quart every four hours.

Should the cough be troublesome, give

Balsam copaiba,1 table-spoonful.
Sirup of garlic,1 ounce.
Thin gruel,1 quart.

Give the whole at a dose, and repeat as occasion may require. A second dose, however, should not be given until twelve hours have elapsed.

Injections must not be overlooked, for several important indications can be fulfilled by them. (For the different forms, see Appendix.)

If the disease has assumed a typhus form, then the indications will be,—

First. To equalize the circulation and nervous system, and maintain that equilibrium. This is done by giving the following:—

Powdered African cayenne,1 tea-spoonful.
Powdered flagroot,1 table-spoonful.
Skullcap,1/2 ounce.
Marshmallows,4 ounces.

Put the whole of the ingredients into a gallon of water; boil for five minutes; and, when cool, strain; sweeten with a small quantity of honey; then give a quart every two hours.

The next indication is, to counteract the tendency to putrescence. This may be done by causing the animal to inhale the fumes of pyroligneous acid, and by the internal use of bayberry bark. They are both termed antiseptics. The usual method of generating vapor for inhalation is, by first covering the animal's head with a horse-cloth, the corners of which are suffered to fall below the animal's nose, and held by assistants in such a manner as to prevent, as much as possible, the escape of the vapor. A hot brick is then to be grasped in a pair of tongs, and held about a foot beneath the nose. An assistant then pours the acid, (very gradually,) on the brick. Half a pint of acid will be sufficient for one steaming, provided it be used with discretion; for if too much is poured on the brick at once, the temperature will be too rapidly lowered.

In reference to the internal use of bayberry, it may be well to remark, that it is a powerful astringent and antiseptic, and should always be combined with relaxing, lubricating medicines. Such are licorice and slippery elm.

The following may be given as a safe and efficient antiseptic drink:—

Powdered bayberry bark,1/2 table-spoonful.
Powdered charcoal,1 table-spoonful.
Slippery elm,1 ounce.
Boiling water,1 gallon.

Mix. Give a quart every two hours.

The diet should consist of flour gruel and boiled carrots. Boiled carrots may be allowed (provided the animal will eat them) during the whole stage of the malady.

The object of these examples of special practice is to direct the mind of the farmer at once to something that will answer a given purpose, without presuming to say that it is the best in the world for that purpose. The reader will find in our materia medica a number of articles that will fulfil the same indications just as well.