Chapter XVI: Front Matter (16)

_Receptivity_ must be considered in every case. In countries and districts habitually immune from sheeppox, all breeds appear to be equally susceptible, the only refractory specimens being sheep that have survived a first attack, and lambs born of ewes that had the disease (naturally or inoculated) during the later stages of gestation. New born lambs, on an exclusively milk diet, are alleged to be somewhat refractory. In a country where sheeppox has prevailed long and extensively, as in Algiers and Brittany, certain breeds of sheep seem to have attained to a large measure of immunity (Nocard). This is doubtless largely due to the survival of the more insusceptible strains of blood, as Algerian sheep carried into France lead to most virulent outbreaks among the native animals (Galtier).

This relative immunity is still more decided when we come to animals of other genera. Though the latest results of research seem to identify the sporidia found in the different forms of variola, yet the long habit of living in an environment found in the ovine race unfits the germ for pathogenic life in various other genera that have their own variolæ. Sacco and Villain reported inoculations from sheep to man, but as the first was experimenting with variola at the same time, and the second did not test his pustules by reinoculation the results are not convincing. Küchenmeister had a general eruption in sheep after intravenous injection of variola of man, but failed to test it by reinoculation. Voisin and Nocard on the other hand were uniformly unsuccessful in attempts to convey sheeppox to man, and the handling of variolous flocks from time immemorial must have led to many cases in man, had he been appreciably receptive. It is virtually the same with cowpox. Huzard vaccinated 2,000 sheep without producing immunity from sheeppox. Voisin had precisely similar results. He further inoculated infants with sheeppox, and later, successfully, with vaccine lymph.

It does not follow that these genera would be insusceptible under all conditions. Yet the failure to immunize against each other would argue a wider divergence of sheeppox and cowpox, than of smallpox and cowpox, or than of bovine and avian tuberculosis.

Galtier failed to inoculate sheeppox on rabbits or Guinea pigs, yet Jourdan, records a destructive outbreak in the Alps, in hares, kept in the same places with variolous sheep.

_Accessory External Causes._ All unwholesome conditions of life, and especially overcrowding, filth, starvation, and neglect contribute to the extension of the infection. Still more so, the importation of sheep, whether in the parks of armies, or in the channels of trade, by rail, or steamboat, through stockyards or markets.

The virus is possessed of unusual vitality, and in the dried condition, secluded from air and light will remain virulent for an indefinite period. Hence the danger of wool, and dried sheepskins. Even in the moisture of an ordinary shed it has retained its infectiveness for five or six months. The sheep that has recovered from the affection may transmit the disease to others for a period of six weeks. The virulence is rapidly destroyed by exposure to free air and sunshine, by a high temperature (140° F.), by dilute HCl (2:100), by carbolic acid (2:100), by zinc chloride (5:100), by potassæ permanganas (10:100), by lime chloride (4:100), or indeed by any of the strong antiseptics.

_Incubation._ This extends from four to seven days on an average, with a minimum of two and a maximum of twenty days. The conditions favoring an early eruption are youth, high condition, and a hot season, or close warm building, with overcrowding. Those favoring a tardy eruption are old age, debility, and above all a cold or wet season with exposure in the open air. Simonds, who inoculated in England in the cold months (October and November) never saw it exceed 13 days. In certain cases, however when the eruption had already commenced in mild weather, the sudden occurrence of a week of cold and wet, would stop it short to start anew on the return of warm weather a week later. In inoculated cases the incubation is shortened, while it is prolonged when the virus is introduced by the digestive or respiratory passages.

_Symptoms._ During the last two or three days of a prolonged incubation and especially in old sheep, there may be some impairment of appetite and rumination, dulness, a stiffness of movement of the hind limbs, and a disposition to lag behind the flock. The temperature may even have risen (104.5° F.), yet Simonds has never seen the febrile symptoms precede the eruption.

There follow, trembling, or rigors, accelerated pulse (80 to 90) and breathing, arched back, anorexia, suspension of rumination, costiveness, redness of the eyes, epiphora, a watery discharge from the nose, gradually becoming more viscid, and a marked hyperthermia (105°, 106° or 107° F.) If the skin is white, a blush, with some heat, is shown in the seat of the future eruption, usually on the parts uncovered by wool, the axillæ, sternum, abdomen, udder, inner sides of the thighs, lower surface of the tail, and the face—especially the eyelids, nostrils and lips.

In two days more, deep red points, like flea bites, appear more or less numerously, in the congested parts of the skin, and in twenty-four hours these have increased to firm rounded papules which are felt to extend into the true skin. These vary in size from 3 to 12 mm. or more. In two or three days the papule has become firmer and less tender, and shows in the centre a paler area where the exudation has resolved it into a vesicle. The characteristic sheeppox vesicle is rounded or flattened on its summit, being rarely pointed as in smallpox, or umbilicated as in cowpox. It is usually surrounded by a pink zone, which is at times infiltrated, firm and resistant. After about the sixth day, the vesicle becomes yellowish from the formation of pus. The pustules, with the surrounding tumefaction, encrease for about three days, when if they have not become confluent nor infected, they begin to dry up, acquiring a grayish crust on the surface which gradually encreases to a thick scab, which in five or six days more is detached leaving a pink, pitted spot covered by forming epidermis. Sometimes no distinct scab forms, but the crust dries, cracks up, and falls off in scales.

All the vesicles do not appear at once, but some earlier and some later, so that the successive stages of the eruption may be often seen together on the same subject, and the case is thereby materially prolonged.

As in other forms of variola the hyperthermia usually subsides with the appearance of the eruption, but as often reappears in some measure with pustulation (secondary fever of reaction), and becomes more severe in proportion to the extent and confluence of the eruption and the occurrence of complex infection.

The eruption may invade the conjunctiva, the cornea (inducing blindness), the nasal mucosa (causing difficult breathing), the mouth (salivation, difficult mastication), the pharynx (difficult deglutition), the stomach and intestines (diarrhœa), the bronchia (cough), or the vulva.

With the occurrence of desiccation, in discrete cases, the fever subsides, the swelling of the skin and head disappears, the discharges from the nose and eyes cease, and the animal is restored to health.

A secondary eruption will sometimes take place, but only papules form, which disappear without reaching maturity.

The duration of discrete sheep pox is usually about three weeks, but it may reach four in cool weather. It is more rapid and more prone to dangerous complications in hot weather. As the members of a flock are usually attacked in succession, it may take three months to pass through a flock.

In _confluent_ or _complicated cases_ the fever of invasion is very high, the sheep dull, prostrate, tender to touch along the back and loins particularly, with hurried, labored, panting, breathing, and mawkish, fevered breath, the weakness increases rapidly, standing even may become difficult, the wool is loosened and falls off in patches, the exposed skin is red, shading, it may be, into a violet hue. The head droops, the lips and nostrils swell, saliva drivels abundantly, anorexia is complete, though thirst may be ardent, a yellowish and even reddish, fœtid discharge may flow from the nose, respiration is difficult, the eyes are watery and deeply sunken, and the head, limbs, breast and abdomen are extensively infiltrated and œdematous.

Fever does not subside with the occurrence of eruption, which may appear thickly over the whole body, the woolly parts as well as the bare or hairy. The vesicles, which have often a dark, unhealthy look, tend to become confluent, and instead of proceeding regularly to maturity, they may remain hard or indolent papules or nodules or blacken and dry up. The secretion, when it takes place, is liable to be a thick, yellowish, fœtid pus. The eruption has much more tendency than with the discrete form to invade mucosæ, and not infrequently the serosæ are involved, especially those covering the lungs, liver and spleen. In the worst cases death may result from the fever before any eruption has taken place, in other cases the extent of the internal lesions tends to hasten a fatal result. With the amount of care that can be given to a flock, confluent cases are usually fatal.

In connection with the itching and scratching of the nose, abrasions and complex infections ensue, resulting in extensive ulceration and gangrene implicating the nasal cartilages and bones. The eruption around the pasterns may lead to shedding of the hoofs, and sloughing of the whole digital structures. Suppurating and gangrenous swellings form subcutaneously and in the lymph glands with fatal results. Blindness is especially liable to happen from the formation of the eruption on the conjunctiva and cornea. Ulcerations and sloughs are common on the internal mucosæ, and even on the serosæ. In implication of the abdominal organs, a fœtid diarrhœa is usually present, and in pregnant ewes abortion is the usual result.

_Lesions._ The cutaneous lesions are in their multilocular structure, the same as in cowpox, but differ materially in size and form. The typical vesicle is small (5 to 12 mm.), and neither broad and umbilicated like cowpox, nor conical and pointed as in smallpox, but round with a slight flattening on the summit. On the same animal may often be found all the successive stages at once, red points or hæmorrhagic spots, vesiculation, pustulation and even desiccation. The early changes are seen in the papillary layer and rete mucosum, in the form of swelling and congestion of the papillæ, exudation, active proliferation of the epidermic and tissue cells, and migration of leucocytes, (embryonic cells polynuclear) vacuolation of the papule, the spaces being filled with a straw colored exudate, and finally, the replacing of this by pus. If the local inflammation is very acute, the pustule may be resolved into a small abscess. On section of the skin the affected parts are found to be the seat of congestion and gelatinoid exudation, extending into the subcutaneous and intermuscular connective tissue, and even the muscles themselves are blackish and their capillaries engorged. The exudation is especially abundant in the dependent parts (head, neck, sternal and abdominal regions, legs). In proportion to the severity of the attack there are congestion, exudation, swelling, and blood extravasation in the lymph glands.

The nasal mucosa is congested, thickened or even ulcerated with abundant, tenacious, muco-purulent secretion and the nasal chambers narrowed or obstructed, and similar changes may be present in the larynx, trachea and bronchia. Spots of ecchymosis and even distinct variolous vesicles are to be expected. The pleuræ are often the seat of congestion, petechiæ, exudation, and discoloration (red or pale). The lung may show congestion and hepatisation in circumscribed areas, or there may be on the surface of such hepatised portions red or grayish foci, like a lentil, pea or bean, the seat of degeneration or forming minute abscesses. The pericardium and myocardium may be involved to a limited extent.

The buccal and pharyngeal mucosæ may be the seats of vesicles, or erosions or ulcers the result of their destruction, and the gastro-intestinal mucosa presents ecchymoses, vesicles, abrasions, and open sores in the midst of inflamed catarrhal patches. The mesenteric and other lymph glands are congested, swollen, softened and friable. Congestions and petechiæ are found on the peritoneum, liver, spleen and kidneys, with, at times, nodular foci. In certain cases congestions and effusions have been found on the pia mater and arachnoid, in the cerebral ventricles and the brain substance.

_Prognosis._ _Mortality._ Mortality varies much with the severity of the special outbreak and the conditions of life, favorable or otherwise, in which the flock is placed. In the milder forms the mortality may not exceed seven per cent, while in the more violent the whole flock almost may perish. A fatality of 20 to 30 per cent is the general average. Yet the inoculated form kills but 2 per cent.

If at the outset there is great weakness and prostration, complete anorexia and high fever, the prospect is discouraging. If the fever is moderate and strength and appetite retained, the case is very hopeful. On its first advent into a new country it causes a far greater mortality than after it has been long domiciled there, and frequent outbreaks have killed off the more susceptible strains of blood. Again very hot weather, or, still more, the prevalence of cold, drenching rains aggravates an outbreak and greatly encreases the fatality.

The loss is not to be measured by the deaths alone. The failure of the crop of lambs, through abortion, the shedding of wool, the loss of sight, hearing, hoofs, digits, flesh, stamina, etc, render recovery far from desirable, in the worst cases, as the animal fails to thrive or pay for its keep. On the contrary it is immune from any future attack, and if left in a thrifty condition it becomes especially valuable in a district where sheeppox prevails.

_Treatment._ Once established in the system the disease will follow its regular course, through all its stages. Yet we can, by dieting, pure air, cleanliness, shelter and even by medicinal measures, do much to render that course a safe one. Cool sheds, pure air, clean floor, dry clean litter and shelter from rain are above all important. The sheep may be separated in different enclosures in small lots of 5 or 6 to prevent crowding, heating, and excitement, and in any case the infected should be removed from the noninfected, and even from each other to avoid infection and reinfection. This is especially requisite in hot weather.

For the strong and vigorous, a diet of sliced roots and meal (oat, bran, linseed, barley, wheat middlings) is good, while for the weak, gruels of oat meal, barley meal, linseed meal, or the same agents dry, may be given. Powdered saltpeter may be given in this (1 oz. to 8 or 10 sheep) and common salt allowed to be licked at will. Drinking water may be given pure, or slightly acidulated with sulphuric or hydrochloric acid, or hyposulphite or bisulphite of soda may be used as a substitute for the latter. The bowels are usually costive, and may be relieved at first by 3 ozs. of sodic sulphate, and later, if need be, by soapy injections. Often during the course of the disease a sudden access of fever may be cut short by a mild laxative, if that is not contra-indicated by existing diarrhœa.

Avoid giving heating agents to bring out the eruption. The severity of any case and the danger of complex infection are usually in ratio with the extent of the eruption.

Lotions of hyposulphite of soda may be applied to the affected parts from the first, and even weak lotions of chloride of zinc after the maturation of the pustules. For the eyes, nose and mouth antiseptic lotions may be called for.

In the advanced stages, in weak subjects, tonics and stimulants may prove useful. To the mineral acid, quinine (10 grain doses) or gentian (drachm doses) or other bitter may be added for valuable stock.

Treatment is only permissible in the case of very valuable animals and when they are surrounded with the most perfect antiseptic precautions, to prevent the escape of the infection.

_Prevention._ As in all dangerous infections this must be the preëminent object, and when a new country has been invaded by the disease, no sentiment nor alleged value of affected or exposed animals should be made the warrant for treatment, nor stand in the way of the extinction of the plague by the most rigorous measures. The recovery of an individual flock is never to be put in the balance with the danger to which other flocks are thereby exposed. To avoid smuggling away of exposed animals, and consequent spread of the disease, the loss should be met by the commonwealth and no foolish idea of administrative economy, should tempt a stock owner to endanger the flocks of a whole nation.

Sheep and goats from countries where sheeppox exists should be absolutely excluded. If, in exceptional cases they are allowed to land on our shores, they should be guaranteed by a veterinary certificate as coming from a noninfected district, by a route free of infection, they should be critically examined by an expert on arrival, and if passed, should still with all clothing and utensils, be subjected to thorough disinfection. The clothing of attendants should be similarly dealt with. If importation is merely across a frontier, a quarantine of 21 days followed by a disinfectant bath should be enforced.

If sheeppox has gained a footing in a flock in a new country, the flock should be at once appraised and destroyed, and the place thoroughly disinfected and shut up for three months. All cars, ships, wharfs, landings, chutes, yards, buildings, parks, roads, etc., used by them should be closed and thoroughly disinfected. All flocks exposed to any such place or thing should be placed in strict quarantine for three weeks, under official veterinary supervision and disposed of, should they become affected.

As an alternative each infected and suspected flock should be secluded in a well fenced place or shed from which all men except the necessary attendants, all dogs and other mammals, including vermin, all birds and as far as possible all flies are excluded. They should be divided into small lots of 5 or 6 placed in separate pens, their temperatures should be taken 3 or 4 times a day, and any one showing a temperature of 104° or 105° F. should be instantly removed to a separate pen, and destroyed as soon as the disease can be identified. In this way a diseased sheep can usually be removed before it has infected its fellows, and at the worst the infection will rarely spread beyond the 5 or 6 animals enclosed in the pen where the first case appeared. It is well to sprinkle the wool of all the flock with a 5 per cent solution of carbolic acid, and the floor or ground with chloride of lime. The diseased carcasses should be thoroughly sterilized by burning, boiling, or immersion in strong acids, or they should be deeply buried, the infected pen disinfected on each occasion, and the hands and clothes of the attendants purified.

Careful treatment in this way will usually cut short the disease with the loss of those only that were already infected when the outbreak was taken in hand, but it must be in the hands of men who are at once experts and vigilant and trustworthy. The English invasion of 1862, under the direction of the late Professor Gamgee, was completely stamped out in four weeks on this plan, whereas the invasion of 1847, met by the expedients of inoculation and quarantine, lasted for four years, with great losses in a number of flocks, and a very heavy bill for continued expert supervision. This should be a wholesome lesson to the American legislators who consider the prompt extinction of infection, by abolishing this source of its increase in the living body, as a wasteful outlay.

_Preventive Inoculation, Ovination._ If it were possible to give immunity against sheeppox by inoculation with the exudate of cowpox, and without danger to the sheep from fatal cowpox, or from its transformation into the more destructive sheeppox, it would be a most desirable resource. But experiment goes to show that vaccination is useless, in the temperate climates at least. Sacco, Hussan, Buniva and others in Italy vaccinated sheep extensively and claimed to have obtained good results, but this has not been endorsed by subsequent observers. D’Arboval vaccinated 1,523 sheep, of which 1,341 contracted cowpox, and out of 429 of these exposed to sheeppox later, 308 contracted the latter disease. Ceely vaccinated two sheep, both of which afterward had mild sheeppox through inoculation. Simonds and Marson vaccinated 306 sheep, 112 of them successfully, and of these last two-thirds contracted cowpox a second time on re-vaccination. Twenty-nine of the successfully vaccinated sheep were inoculated with sheeppox lymph, and in every case successfully. It is obvious that vaccination, as a protective measure, is absolutely untrustworthy in France or in England. Under the warm skies of Italy, as in Persia, there may be a close relationship between the two diseases, yet in Italy sheeppox was constantly prevalent, and it is to be feared that the immunity in a number of cases was due to a previous attack of that disease rather than to the vaccination. It should be noted that in Persia sheeppox is said to be communicable to man, while in England, Ceely failed to transmit it.

Ceely suggested variolisation with human smallpox as a preventive of sheeppox, but Simonds and Marson failed to convey smallpox to the sheep, though the same animal readily contracted sheeppox. One can hardly contemplate Ceely’s proposal with equanimity. Immunity for sheep would be dearly bought at the cost of a general diffusion of smallpox virus.

_Ovination_ or inoculation with the lymph of sheeppox is the only available method of immunization. It entails, however, an extraordinary multiplication of the virus in each inoculated animal, and considering the numerous loopholes for its possible diffusion it can only be looked on as a very dangerous and usually, in the long run, a very expensive resort. The experience of England, above referred to, is eloquent in witnessing against ovination, and “in Prussia and Austria the dissemination of sheeppox went hand in hand with inoculation.”—Friedberger and Fröhner.

On the other hand _ovination_ is not fatal to the flock operated on. The mortality is often below 1 percent., and virtually never exceeds 4, with a general average of about 2 per cent. It is this comparative impunity of the inoculated flock which closes the eyes of most persons to the great danger to a whole country and the wasteful prodigality of the operation.

_Ovination_ further shortens the duration of the outbreak in a large flock, passing all through the disease in 21 days, whereas as contracted by simple exposure, the duration of the outbreak may last 90 days or more. It further enables the owner to give such protection, shelter and care as will guard the flock against exposure and dangerous complications. But while preferable to the abandoning of the disease to its natural course, it is always to be strongly condemned, where it is possible to adopt the method which detects the sick animal in the incipient stage by thermometry, and does away with the infection by its removal, followed by disinfection. The only excuse for ovination is the general prevalence of sheeppox on an island or other secluded district where there is no great added danger from the further diffusion of the virus, and when its simultaneous practice over the whole region can be made the basis for universal disinfection and the definite extinction of the contagium.

_Technique of Ovination._ The lymph (“ovine”) should be taken from a mild case of the disease, and from a vesicle at full maturity (about the 6th day), but containing as yet a clear, translucent exudate, without turbidity or other indication of formation of pus, or other infection. Inoculation is made by preference on the bare lower surface of the tail near its tip or 3 to 4 inches behind the anus. If this is unsuitable, the inner side of the ear, an inch from the tip is usually selected, though there is here an added element of danger, owing to its proximity to the eye. The insertion is made with an ordinary suture needle, which is introduced obliquely under the epidermis about one line, and pressed upon with the thumb as it is withdrawn. A still better instrument is the inoculation needle or lancet with a groove or spoonlike hollow on one side. Or the skin may be scratched or abraded with the lancet, as in vaccination, until serum oozes, when the virus is rubbed on and the part is covered with a piece of sticking plaster. On the third or fifth day the flock is again examined and those that have failed to _take_ are ovinated anew.

The virus is most conveniently taken direct from the affected sheep, but it may be preserved in capillary tubes, or on glass or ivory points, or mixed with glycerine between glass plates, or finally, the first scab well dried may be preserved and utilized, a minute portion being inserted with the lancet in a pocket made under the epidermis.

Attempts have been made to secure a mitigated and safer virus, by diluting the lymph with water or normal salt solution (1:50–150) (Peuch), by amputating the seat of inoculation (the tip of the ear) on the 4th or 7th day, when the vesicle is formed (Galtier), by taking a susceptible sheep and inoculating it with sheeppox virus for ten consecutive days, and then selecting for use the lymph from the papule of the sixth inoculation. The inoculations of the seventh day and later give rise to no papule even (Pourquier). By this means it is claimed that the inoculated disease remains strictly local, passes through its successive stages in a shorter time (15 days or less), and is perfectly harmless to the sheep inoculated. Nocard and Mollereau sought the same end by mixing the virus with oxygenated water, and Semmer and Raupach by heating it to 130° F. In view of the facts that it is only under extraordinary conditions that ovination is permissible at all, and that the mortality, resulting from it can be kept down to about 1 per cent., it seems hardly worth while to attempt to obviate this loss, by any method which may come short of the full measure of immunity.

Ovination confers immunity for a year or longer.

The care of the flock during eruption is the same as in sheeppox contracted in the usual way.

SHEEPPOX IN GOAT. VARIOLA CAPRINA.

The goat can be successfully inoculated from the sheep, the resulting vesicles being smaller and less prominent, and the disease assuming a milder type. It is alleged to pass naturally from sheep to goat, and from goat to sheep, as well as from goat to goat but, on the whole, it is a rare disease and goats have been known to live in flocks of sheep attacked with sheeppox, without themselves contracting the disease. The malady seems to be of little account to the goat, yet in sheep countries, the interests of flockmasters would demand that it should be stamped out as vigorously as the same disease in sheep.

GOATPOX; VARIOLA CAPRINA.

In Persia according to Bruce goats suffer from a form of variola, having larger vesicles, umbilicated and approximating to, if not identical with cowpox. In Algiers there is found a goatpox from which sheep are alleged to be immune (Nocard, Peuch, Bremond, Galtier) so that further observations are wanted to put the different forms of variola of the goat in their proper places. In a country where sheeppox is constantly present, there is of course the possible source of fallacy of experimenting with animals that have already had the disease, therefore it would be expedient to put all forms of goat variola under police control.

SWINEPOX. VARIOLA SUILLA.

Variola appears to be rather more frequent in swine than in goats. Ficanus as quoted by Joubert saw it in 1567, contracted it was supposed from smallpox patients. It was noted by Ramazini in 1690, by Stegman in 1697, and later by Gerlach and others. In 1891 517 cases were reported in Hungary. It is said to be derived from man by the use of bed straw for litter and from sheep by occupying the same stall. It can be transmitted experimentally from pig to pig, from pigs to goats, and from goats back to pigs (Gerlach). It is also claimed to pass from the pig to man (Freidberger and Fröhner). Young pigs are especially subject to it and one attack confers immunity for the future.

_Symptoms._ After a febrile condition of variable length, but usually of a high intensity, red spots appear on the head, neck, chest, belly or inside the arms and thighs, at first like flea bites, but passing through the stage of papule to become vesicular on the sixth day. About the ninth or tenth day they become purulent, and in two or three days more a black, concave, circular crust has formed which is soon detached. The eruption may be _local_ or _general_, _discrete_ or _confluent_ and the issue of the case will depend much on this character. In exceptional cases the eruption invades the mouth, eye, throat, stomach, or intestines. Croker notes the accompaniment of a fatal lobular catarrhal pneumonia.

It must be carefully distinguished from urticaria, eczema, and eruptions due to pustulating irritants.

_Treatment_ is in the main the same as for sheep, care being taken to secure perfect cleanliness, pure air, dry clean litter, easily digested food, and protection from crowding, undue heat, cold or wet. Buttermilk and other acidulous and diuretic drinks are recommended, and careful attention to the state of the bowels throughout.

_Prevention_ is still more important, and better than any treatment would be the most rigorous measures for its extinction along the lines laid down for sheep pox. Whether the infection has been derived from man or sheep it must be looked on as eminently dangerous to the class of animal from which it originated, and every available means used for its extinction.

DOG POX: VARIOLA CANINA.

Dog pox is rare, the affection occurring especially in the young. It is said to be derived in certain cases from smallpox patients (Weiskopf), and in others from sheep pox (Röll). The latter claims that the dog has also its own specific form. Dupuis and others claim experimental transmission from man to dog. At the same time eruptions connected with gastric or hepatic disorder, distemper, eczema, or aphthous fever are liable to be mistaken for it.

_Symptoms._ The young animals suffer from fever for a day or two, followed by heat and redness on the sides and belly, and points of deeper red, like flea bites, which gradually evolve through papules and vesicles to pustules, and terminate in crusts, that drop off leaving round bare spots. The vesicles may appear locally or generally and may be discrete or confluent. Sucking puppies, when attacked usually perish.

In _treatment_ the same hygienic measures are demanded as for other animals, special care being required to keep the bowels and kidneys acting in a healthy manner. Perfect cleanliness must be secured, and nonstimulating easily digested food. Excessive fever would demand tepid baths, cold sponging, or acetanilid, and undue warmth, crowding and cold exposure must be alike guarded against.

In view of the alleged sources of the disease in man and sheep, the strictest seclusion of the affected dog, in disinfected surroundings will become absolutely essential and when this cannot be carried out he should be summarily destroyed.

VESICULAR EXANTHEMA OF HORSES.

_Definition_: Vesicles usually on external genitals, with fever and
infection. Causes: Contagion by coition, clothing or stable utensils;
inoculated on man or cow, resembles cowpox, but a first attack does
not always immunize a stallion; inoculable on sheep, goat and pig.
Symptoms: Incubation one to six days; local redness, heat, swelling,
tenderness, papule, vesicle, pustule, scab, desquamation,
depigmentation on genitals or in sucklings on mouth, lips, nose; may
extend to mammary and inguinal regions, with swelling, stiffness and
constitutional disturbance. Diagnosis from dourine. Treatment:
Cleanliness, astringent, antiseptic lotions; open and disinfect
abscesses; laxatives or diuretics. Prevention: Withhold from breeding.

_Definition._ An acute infectious disease, manifested by hyperthermia, hyperæmia, and the formation usually on the external generative organs of a crop of papules rapidly progressing to vesicles, pustules and open sores, and attended by great local irritation and itching. It runs a mild course and recovery ensues spontaneously in about fifteen days.

_Causes._ The disease is only known as a contagious affection, propagated from animal to animal by breeding together, or by using the same comb, brush or rubber, or by sucking, and in rare cases by other accidental or experimental inoculations. To make a successful inoculation the virus must be taken from the vesicles or pustules. When transferred to man or ox it develops an eruption which is indistinguishable from cowpox (Trasbot, Peuch, Galtier). Still a first attack does not always confer immunity, as stallions may have two successive attacks within a few weeks (Steinhoff). This implies that either this is not genuine cowpox, as claimed in France, or that two different exanthematous affections have been classed as one. Inoculation with the virus has produced a characteristic eruption in sheep, goats and pigs.

_Symptoms._ After a period of incubation of from one to six days there appear heat, swelling and tenderness of the affected part, followed by the formation of papules, gradually passing into vesicles, pustules and scabs which scale off, leaving a white depigmented surface. In stallions and mares the usual seat of the eruption is the external generative organs; in young sucking animals the mouth, lips, nose and quarters, and in inoculated cases wherever the virus has been implanted.

In the _mare_ there is swelling of the lips of the vulva and redness of the vaginal and vulvar mucosa with points of a darker red, which become firm, papular, vesicular and finally pustular. A similar eruption shows on the skin of the swollen labiæ, on the lower surface of the tail and on the hips, though on these points the phenomena are obscured somewhat by the abundance of pigment. The contents of the vesicles are at first limpid but gradually change to opaque yellowish white, brown, or even red from slight blood extravasation. It causes not only marked tenderness but great itching so that the patient rubs the tail and rump, rupturing the vesicles, causing blood extravasations and retarding healing. The sores are primarily two or three lines in diameter but may widen and deepen under the friction. The surface may be red and angry and covered by a yellowish viscid discharge. When they heal they leave on the dark skin, round spots white and devoid of pigment. The itching during the acute stage of the disease, leads to generative excitement, frequent straining, contractions of the erector clitoris and ejection of urine. The animal appears to be constantly in heat, yet the absence of hyperthermia shows that there is no constitutional disorder nor central nervous affection. The disease appears to be purely local.

In the _stallion_ after a similar incubation, the penis and usually the sheath become swollen and congested and if free from pigment there are dark points as described in the vulva. These points become firm, prominent, and finally vesicular and pustular. If continued in service the resulting sores may extend and prove protracted. In the absence of service they tend to heal about the fifteenth day. The eruption may extend on the scrotum, the inner side of the thighs, the throat, the lower surface of the neck, and the inside of the forelegs; on any parts indeed that may become soiled on mounting the mare. The meatus urinarius is red, swollen and angry, and shows a muco-purulent discharge. Generative excitement is shown by the more frequent rising and falling of the testicles, protrusion and retraction of the penis, and the frequency of urination.

In bad cases in both sexes the eruption encroaches more widely on the skin, and subcutaneous abscesses may form on the vulva, anus, tail, between the thighs or on the scrotal, mammary or inguinal regions. These are attended by extensive local swellings extending on the croup, or down to the hock, or forward to the hind limbs. In such cases there is more or less stiffness or lameness, with constitutional disturbance, hyperthermia, gastric disorder and emaciation.

_Diagnosis._ This disease is distinguished from dourine by the known absence of the latter from the locality, by the ready transmission, of the benign exanthema to cattle, by the entire absence of paresis or mental hebetude, by its rapid progress and early recovery, usually in fifteen days.

_Treatment_ consists in thorough cleanliness, and the application of cooling, astringent, antiseptic lotions to the affected parts. Solutions of borax, boric acid, sulphate or chloride of zinc, permanganate of potash, corrosive sublimate, chlorine water, creolin, lysol, carbolic acid, or other such agent with glycerine will act promptly and well. In the severe cases with secondary abscesses the latter must be opened and the cavities treated antiseptically. Cooling laxatives and diuretics with salicylates or hyposulphites may also be desirable.

_Prevention._ No animal having sores nor discharge from the generative organs should be used for breeding. The owner of the animal infected by breeding has a good claim for damages.

VESICULAR EXANTHEMA IN CATTLE.

Definition: acute infections, eruptive affection, usually of the
genitals, in cattle, transmitted by breeding, and marked by
congestion, papules, vesicles and pustules. Cause: infection by
coition; by contact, by gutter, by tail, by licking, in sucklings.
Oxen and non-pregnant cows suffer. Symptoms: incubation 1 to 6 days,
cows have swelling, red points, papules, vesicles and pustules on
vulvar mucosa and adjoining skin, with profuse glairy discharge, and
it may be fever: bull has matting of preputial hairs, frequent
micturition, swollen sheath, red penis, vesicles, even necrotic ulcers
and distortion. Immunization short, uncertain. Treatment as in horse.
Prevention: seclusion and disinfection of animals, disinfection of
stalls, gutters, rubbing posts, trees, complete segregation of sick
from healthy.

_Definition._ An acute eruptive affection, attacking particularly the generative organs of breeding cattle, manifested by congestion, papules, vesicles and pustules of the mucosa and skin and transmitted largely by copulation.

_Causes._ The one known cause is infection and the most common mode of communicating it is by the generative act. In this it agrees with the mild coital exanthema of horses, and the two affections have been considered as identical with each other and with cowpox (Trasbot). The similarity of the symptoms and the duration of the disease sustain this view, but, if correct, it is probable that the affection has undergone a distinct modification which adapts the microbe especially to life in the genital canal, and to the maintenance of its virulence for a longer period, and finally, robs it of the power of producing any permanent immunity. Cowpox, though raised on the lips of the vulva, the inner side of the thighs and the abdomen where it can be easily reached by the tail does not tend to implicate the genital canal, and it so quickly secures immunity, that neither male nor female would be likely to long convey the disease. Yet in both horses and cattle experience shows that the acquired immunity of vesicular exanthema is very short lived.

Cattle, much more than horses, are liable to transmission of the disease by other channels than coition. Contact with the same soiled stall and gutter, the direct transference to adjoining animals by the soiled tail, and the greater frequency with which they lick themselves and others doubtless contribute to this. The frequency of non-coital infection is shown in Numann’s cases affecting the anus and sheath in oxen; also in Fenner’s long list of cases in 669 non-pregnant cows, in a number of cows in advanced pregnancy and in calves of a few weeks old (Friedberger and Fröhner).

_Symptoms. In Cows._ After an incubation of one to six, (or exceptionally ten) days, there occur swelling and redness of the lips of the vulva, and the vaginal mucosa with here and there dark red points, and an abundant clear, glairy discharge. The red points may become firm and papular, and an exudate beneath the epithelium transforms them into vesicles at first translucent but later yellow or brown as pus cells accumulate. The clear mucous discharge meanwhile becomes opaque and, as the pustules open, forming sores, yellowish and purulent. This discharge soils the tails and hips, drains out on the back part of the stall and the gutters and is carried by the tail to the udder and to other stock. Itching may be severe and the constant rubbing and switching of the tail, may irritate the sores and cause them to deepen or extend, beside favoring septic infection and local necrotic processes. In such cases there may be more or less fever, impairment of appetite, rumination and digestion, and of the secretion of milk. Abortion is not unknown though exceptional.

_Symptoms. In Bull._ The matting together of the long hairs of the prepuce may be the first indication of the disease, attended or followed by frequent micturition, or by standing with the tail raised and the accelerator urinæ pulsating over the ischiatic arch as if passing urine. The sheath appears swollen, the penis red granular, and angry, with red spots, and even the scrotum may be involved in the enlargement. The red points advance as in the female through the different forms of papule, vesicle and pustule to the formation of sores which are more or less red and angry. There may be an indisposition or even inability to protract the penis, and the bull may be tardy to serve, or in case the organ is erected and used, blood may ooze from the respective sores. The disease usually lasts about two weeks, but may recur a few weeks later in connection with a new infection. In aggravated and prolonged cases there may be local septic and necrotic processes, and general fever and digestive disturbances. Distortions of the penis may render the subject permanently useless as a sire.

_Treatment_ is essentially the same as in the horse. Antiseptic and astringent solutions (sulphate of zinc, iron or copper (2:100), nitrate of silver, carbolic acid, corrosive sublimate, lysol, creolin, etc.) may be used to advantage. Laxatives and diuretics may be called for.

_Prevention._ This would require the temporary seclusion and final disinfection of all animals attacked, the thorough cleansing and disinfection of the stalls and gutters, as well as all posts, trees and fences on which the animals rub themselves. The attendants should use no combs, brushes, sponges nor rubbers indiscriminately on the sick and healthy. They should disinfect their hands and, if necessary, their clothes after having handled the sick and before handling or milking sound animals. An obvious precaution is to place the sick and healthy in separate buildings and yards.

INFECTIOUS GENITAL CATARRH IN RABBITS.

Freidberger and Fröhner record a very contagious catarrhal affection of the vulva and prepuce in high bred rabbits, and conveyed from animal to animal by sexual congress. The characteristic symptoms were extensive swelling of the parts and an abundant muco-purulent discharge.

Injection of the genital passages with a sulphate of copper solution (1 to 2 per cent) for several weeks in succession effected a cure.

INFECTIOUS ULCEROUS STOMATITIS IN LAMBS AND KIDS.

Prevails in France. Predisposing causes, bad hygiene. Specific cause,
streptococcus. Pathogenesis, to lambs and kids through sucking,
drinking, feeding; inoculable on Guinea-pig, not rabbit. Lesions: like
thrush, congested patches, with curd-like concretion; epithelium,
leucocytes, microbe; in bad cases gastro-enteritis, hepatitis, or
pneumonia. Symptoms: hyperthermia, refusal of teat, froth on lips,
dulness, debility, emaciation, death in 15 days; in mouth, concretions
and red raw sores; cough, hurried breathing, diarrhœa; subacute cases
have little fever, or infection. Mortality 8 per cent. in acute cases,
none in subacute. Prevention: separation and disinfection of fold.
Treatment: antiseptics to mouth; borax, sulphites, chlorate of potash,
sodium salicylate, iron chloride, copperas, silver nitrate. Feed
through tube or syringe. Internally, sulphites.

This is found in all parts of France, as described by Besnoit.

_Causes._ The predisposition, as in the case of many other fatal internal inflammations, depends largely on faulty hygiene, foul, ill ventilated, hot, close, damp, overcrowded folds, without sunshine, drainage or free access to the outer air.

The _specific cause_ is a large coccus, isolated or in chains of 2, 3, 4 or more (streptococcus), and found abundantly in the pultaceous buccal exudate, and in the internal lesions developed by autoinfection. It grows readily in bouillon in the form of a precipitate in the bottom of the liquid, in gelatine and glucose in very small, thin colonies, and on potato in creamy masses. It is stained by anilin and by Gram’s (iodine) preparation.

_Pathogenesis._ Inoculable on the Guinea pig, it is harmless to the rabbit. It is readily conveyed to lambs and kids by inoculation, or through the teats, by licking, drinking, feeding, etc. Acute cases are very virulent, subacute very little so. Isolated cases of the latter are not uncommon.

_Lesions._ The buccal lesions are like those of _thrush_ (_muguet_). The mucosa is more or less congested and reddened with raised patches, of varying extent, of white, curdy looking concretions, composed of excess of epithelial cells and leucocytes with an abundant exudate. The specific coccus is present in great numbers and often in almost pure cultures. The internal lesions found in the more acute and fatal cases are mostly in the form of gastro-enteritis, hepatitis and pneumonia, containing the specific cocci, and due to the inhalation or swallowing of the virulent buccal products.

_Symptoms._ In the _acute cases_ an intense hyperthermia is the first symptom, speedily followed by refusal to suck, the accumulation of froth around the lips, great dulness and lassitude, prostration, rapidly advancing debility, and emaciation, and death in 15 days in a condition of marasmus and inanition. When the mouth is opened the curdy white or yellowish white patches of exudation are seen with an abundant glairy mucus, and occasionally red, raw, angry patches from which the morbid growth has been detached. The symptoms of pneumonia or of muco-enteritis are usually in evidence, with or without diarrhœal or dysenteric discharges. Acute cases are extremely contagious.

In _subacute cases_ the lesions are confined to the buccal mucosa, as curdy white, raised concretions with ulcerous surfaces, frothy lips and refusal of the teat, but without marked hyperthermia or constitutional disturbance. Contagion is little marked, the disease appearing enzoötically in flocks, or even as but one case in each of several flocks.

_Mortality._ Eight per cent. of acute cases may perish, but the subacute nearly all recover.

_Prevention._ When the disease has appeared in a flock, or in its vicinity, the mouths of the lambs should be examined daily and affected subjects and their dams carefully separated. A thorough disinfection of the fold is imperative.

_Treatment._ Use antiseptics on the mouth, selecting the non-poisonous articles. Borax may be rubbed freely on the patches. Solutions of sulphite, bisulphite or hyposulphite of soda (1 oz. to 1 qt.) may be used at frequent intervals on the mouth; chlorate of potash (5:100), sodium salicylate (1:100), iron chloride (1:100) may be used. Ulcerous patches may be cauterized by iron sulphate, silver nitrate, or the potential cautery. Besnoit advises mercuric chloride (1:1,000) for cutaneous lesions, but this would be unsuitable for either mouth or lips. The strength must be sustained by the dam’s milk given through a tube or syringe. For gastric lesions the sulphites may be given.

CONTAGIOUS ABORTION.

Definition: Premature expulsion of non-viable fœtus. Synonyms.
Susceptible animals: cows, goats, sows, mares. Accessory causes: Ice
cold drinks at periods of ovulation, frozen aliments, ice cold bath or
rain storm, mechanical injuries, unwholesome fermentescible food,
indigestible foods, close stabling, heavy milking, early breeding,
inbreeding, stagnant water, ergot, smut, vegetable irritants or
ecbolics, constitutional diseases, irritation of generative organs,
death of fœtus, urinary calculi, odor of carcass or carrion,
contagion, experimental infection between cows, between mare and cow,
relation to omphalitis. Nocard’s streptococci and bacilli, Bang’s
bacillus with best growth in two distinct grades of oxygenation,
Galtier’s observations, bacterium of the Colon group in America,
infection of the calves (pneumonia). Various kinds of infectious
abortion. Acquired immunity, variable in different forms. Immunized
cow still infecting. Symptoms. Lesions. Abortion in mares.
Therapeutics. Prevention: Protection of a sound herd, guarantee with
purchase, government control, precautions with male or unimpregnated
female, with pregnant. Extinction in a herd, separation, disinfection,
disposal of abortion, manure, urine, disinfection of animal, of
genital organs, precautions as to service, new born, fields, ewes.
Disinfectants, subcutem or in muscles.

_Definition._ The premature expulsion of the product of conception before it is viable out of the womb. Strictly speaking, a parturition in which the offspring is so far matured as to be _viable_ is a _premature parturition_, while if it is _non-viable_ it is an _abortion_. Vulgarly, however, as applied to herds, the term is used for any early parting with the fœtus. In this wider sense infectious abortion is _the premature expulsion of the fœtus owing to an infectious catarrh of the womb, transmitted from one animal to another by the transference of the microbe_.

_Synonyms._ Infectious Abortion, Enzoötic Abortion, Epizoötic Abortion.

_Animals Affected._ Abortion is most common in cows, and less frequent in ewes, goats, sows and mares.

_Forms and Accessory Causes of Abortion._ It was formerly supposed that abortion in herds was mainly due to mechanical and chemical agencies acting injuriously on the system, and in adopting the explanation of a particulate, transferrable, infectious agent for the habitual widespread forms of the disease, we should not forget these accessory causes, many of which by themselves cause sporadic abortions without the intervention of an infectious element.

The free _consumption of ice cold water_ by the healthy dam causes active gastro-intestinal peristalsis and vigorous movements of the advanced fœtus, which can be seen or felt in the right flank, so that this is often resorted to, to determine whether the animal is pregnant or not. If this is frequently repeated or carried to excess in susceptible animals it will at times cause abortions. As in all other cases of mechanical or physiological disturbance, this is most operative at those periods of constitutional changes, which if the animal had been unimpregnated would have brought about ovulation and œstrum.

The greedy ingestion of _cold aliments_, like _frozen roots_, or green vegetation covered with _hoar frost_, may have a similar action, the more so that such aliments are extremely fermentescible and liable to cause tympany and undue pressure on the gravid womb.

Even without ingestion, exposure to _cold rain or snow storms_ or the _plunging in ice cold water_ tends to produce excessive peristalsis and fœtal movements and thereby prove injurious.

_Mechanical injuries_ to the abdomen as _crushing by a gate_, _kicks_, _hooking with horns or tusks_, _hounding with dogs_, _riding of each other when a cow is in heat_, are liable to produce congestions, detachment of fœtal membranes, and even death of the fœtus.

Very _fermentescible foods_ like those following a wet season or _bad harvest_, or those made of the leafy albuminous plants like lucerne (alfalfa), sainfoin and clover, act injuriously in the way of causing tympanies and compressions, but it must also be recognized that we are here dealing with fodders abounding in bacterial ferments, and that some of their products may act physiologically as ecbolics, even if the bacteria themselves do not colonize the genital passages as infections.

_Insufficient food_ or very _innutritious forage_, too _close stabling_, _heavy milking_, _early breeding_ (dam or sire), _inbreeding_, are liable to lower the general stamina and throw the system more open to the action of other factors.

_Stagnant_, _corrupt drinking water_ has been charged with causing abortion, and the trouble has ceased when it has been withdrawn, but it is difficult to estimate its value in different cases—disturbing digestion, fermentation, poisoning, or introducing of actual infection.

_Ergoted grasses_ and _smut_ in maize, wheat or oats, have been often charged with wide spread abortions, and though each has in turn been administered in large and continuous doses without causing abortion, this does not invalidate the many cases in which it manifestly had that effect, nor does it show that obstetricians have been mistaken in their almost immemorial trust in ergot as an ecbolic. It must be recognized, however, that grown under different conditions, of sunshine and shade, and harvested at different stages of its development, ergot varies greatly in its physiological action, as it does also from having been overkept and thus one specimen is effective or dangerous while another is absolutely ineffective. The specific action of the alkaloids in determining contraction of involuntary muscular fibre, is seen alike when used medicinally and when acting as an accidental toxic agent in causing spasms, nervous torpor or paralysis, delirium; gangrene of the feet, tail or tip of the ear; or contraction of the womb and expulsion of its contents. Like other agents mentioned ergot is at times an active ecbolic when coöperating with other similarly operating agencies.

_Irritant vegetables_ of various kinds are to be dreaded. Such as act on the bowels and kidneys, keeping up a constant diarrhœa and diuresis, are quite liable to cause abortion in susceptible subjects. _Savin_, _tansy_ and _rue_ have obtained a bad reputation in this sense.

_Cotton root bark_ is an active ecbolic, but is not likely to harm animals unless deliberately administered.