Diagnosis in Sheep and Goats. This is based on the same phenomena as in cattle; the sudden and exalted hyperthermia, blush or petechiæ of the visible mucosæ, concretions on the lips, gums and skin, epiphora, salivation, prostration, emaciation and diarrhœa. These last symptoms are, however, less marked than in cattle and the mortality and infectiousness are materially reduced. Pneumonic complications are much more common in sheep.
Mortality. Among native cattle in the Steppes the mortality is 30 to 50 per cent. whereas elsewhere it is 90 to 95 per cent. Among sheep in Austria it reached 60 to 66 per cent. Among camels in Asia and Africa the fatality proved as high as among cattle. The Italian buffalo usually recovered after seven days illness.
Treatment. The therapeutic treatment of cattle affected with cattle plague has been eminently unsatisfactory and is so certain to become a means of extension of the disease that it is legally prohibited in all countries, in which the plague has not been allowed to become generally diffused. Where it has become general in an unfenced country in which accordingly its permanence is virtually ensured, it may be employed.
Serum-therapy is advocated by Refik Bey. An animal is hyper-immunized by repeated inoculations. His blood is then withdrawn and the serum obtained from it is injected in a dose of 25cc., subcutem, at a temperature of 104° F. The temperature is taken from the 3d to the 5th day and if it does not at this time rise above normal the treatment is ended. If still above normal a second dose of 25cc. is given. It is claimed that the serum is harmless and may be safely given in a single dose of 50cc. in case it is impossible to keep watch of the animal for five days.
Prevention by Immunization. Semmer attempted this by inoculating cattle with virus which had been weakened by heat or by passing it through the body of a Guinea pig. The results were, however, far from perfect and even in Russia the method failed of any wide acceptance. Koch and Edington in South Africa practised extensive inoculations with a mixture of the virus in bile. Still better results are claimed by Danyoz, Bordet and Theiler in the Transvaal. These treated the animals by injecting 25cc. to 50cc. of highly immunized blood, defibrinated, and while the subjects were thus rendered temporarily insusceptible, they were exposed to infection by contact with diseased animals.
As with serum-therapy, measures of this kind are only permissible in a country in which cattle plague is already generally diffused, and where there are no fences to limit the continued diffusion of the infection. The preservation of the cattle artificially infected until highly immunized, and again of the sick cattle requisite to give the disease to the cattle operated on, and finally of these last through the mild attacks that are to render them immune, affords an endless number of loopholes for the escape of contagion which would forbid the adoption of the method whenever the extinction of the disease is possible. When on the other hand a disease is already spread universally in a country destitute of fenced enclosures, in which herd mingles with herd in the most perfect freedom, and where accordingly extinction is impossible, the method is admissible and even commendable as a means of reducing the otherwise ruinous mortality.
Exclusion and Extinction of Cattle Plague. For countries adjoining lands infected with cattle plague such general measures as the following are imperative: Prohibition of all imports of cattle, sheep and other ruminants, camels and swine from such infected countries, also of the fresh hides and other products of such animals, and of litter, fodder and other things that may have been stored in the buildings with infected cattle or otherwise soiled by them. Prohibition of imports of all cattle or other ruminants from adjacent countries (which may be plague-free), but which animals have been carried in undisinfected cars or boats that had been in previous use for such species of animals drawn from infected countries, or that had been passed through infected countries, yards, buildings, loading banks, chutes, piers, gangways, or other places, or furnished with fodder, halters or appliances from such infected localities. In Eastern Europe the practice is to patrol the frontiers day and night to prevent the smuggling of cattle through from the infected country. Infected animals or herds, that it is sought to pass, are turned back or slaughtered. Sheep from countries that had been previously infected are often admitted on affidavit of the official veterinarian in the country from which they come, that during the three months before they left, there had been no contagious disease of cattle nor sheep in the locality, and on the further condition that they shall be slaughtered at the point of entry, or, if brought by rail, at the nearest slaughter house approached by such railroad after entry. In France, sheep, sent from Russia by sea, in French bottoms, certified as above by the Russian authorities, and accompanied on the voyage by a French veterinarian and certified sound by him, are allowed to circulate freely after three days detention at the port of arrival without evidence of disease.
In the United States the 90 days quarantine of cattle (dated from the time of shipping at the foreign port), and the 15 days for sheep and other ruminants under strict veterinary supervision is safe as regards the importation of cattle plague in live animals. The greatest danger will doubtless come from intercourse with the Phillipines, which were infected with the cattle plague during the recent war. The greatest possible precautions as regards the carriage of cattle on transports or other ships, will be necessary. Not only should no Phillipine cattle be imported, but no vessel, that has carried Phillipine cattle or sheep, should be allowed to take on board home cattle nor other ruminants until it has been thoroughly disinfected.
Cattle or sheep should be rejected when imported on ships which, on the same voyage or a recent one, carried fresh hides or other fresh products of animals, derived from a country in which rinderpest exists.
Hides that are thoroughly dried and salted, those that have been freely exposed for one week to the sun and air, and such as have been treated by active antiseptics, (caustic quicklime, mercuric chloride, lime chloride, formalin, phenic acid, etc.), need be held under no such restriction. The same applies to thoroughly dried, sunned and aired hair, wool, hoofs, horns, bones and sinews. Rendered tallow is equally safe.
Extinction of Cattle Plague in a Country. This should never be called for on the American Continent. The introduction of such a deadly disease, with such a short period of incubation, and such severe symptoms and rapid course, would argue a most reprehensible carelessness, which it is to be hoped will never be shown by the Federal Bureau of Animal Industry. Yet under the stress of a great European war this plague invariably overleaps the barriers successfully maintained in time of peace, and the same has happened to the two great English-speaking powers in connection with the wars in South Africa and the Phillipines respectively and therefore it cannot be said that importation is impossible under any possible circumstances.
In case of a recent importation the infection would be easily controlled. Trace at once to its destination every bovine animal and other ruminant that arrived on the infected vessel, and all that came in contact with them since, or with the gangways, wharfs, streets, highways, yards, houses, fields, cars, loading banks and other places and things that might have been contaminated; stop all cattle and sheep traffic or movement for a large area around each centre of possible infection caused by such cattle; remorselessly kill every head of such animals carried by such vessel, or that came in direct contact with them; bury, burn, boil or dissolve in mineral acids, every animal thus exposed; thoroughly disinfect the importing ship, and every house, place or thing the imported stock came in contact with, together with all the dejections and debris, and even the surface of the graves; make a census of all cattle within the different quarantined areas, and hold the owners or custodians responsible, under a heavy penalty, to report every death and every case of illness; whenever the cattle plague is found in a place dispose of the entire herd as has already been done with the infected imported stock, and in a very few weeks the plague can be completely extirpated. The violence of the individual attack, and the very short period of latency, makes the work incomparably easier than the extinction of lung plague. There is never a long period of uncertainty (incubation), there is virtually never a slight or occult case of the disease, there is no equivocal chronic form of the affection. The attack is made boldly and above board, and can be met successfully if met promptly and energetically. The danger in such cases lies, less in the nature of the disease, than in the army of foolish, even if well meaning, meddlers, who denounce the temporary interference of trade, the payment of indemnities to the cattle owners, the interference with private property, the destruction of valuable thoroughbred herds, the interruption of the dairyman’s business, the cost of disinfection, and a thousand other things, and who too often succeed in hampering and delaying action, until the infection has reached and spread over great unfenced territories thereby getting beyond control, or, short of this, has so established itself as to necessitate the outlay of a hundred thousand for every hundred that would have been demanded at first, and a long continued restriction of trade in place of the very transient interruption required by early, sharp, decisive action.
One of the most important prerequisites is that every state, but especially those on the seaboard and with ports of entry, should enact such laws as would make it possible for the Executive to act at a moment’s notice and to call in the help of the Federal Government to make an early and effective application of the only successful remedy. Most things can wait for the call, assembling and action of a legislature; the infection of cattle plague can not. Such laws are not superfluous. If never called for they still show a wise provision against a terrible, though remote, possibility; if really called for and they are not found ready, the great cattle industry and even the agriculture of the continent may be largely sacrificed by the neglect.
As guardian of the interests of The Philippines the United States is to-day called upon to consider the question of exterminating the disease which our interference brought upon the islands. On the unfenced lands of these islands we have to face on a smaller scale the problem of stamping out the plague which has baffled the wisdom of Europe and Asia. The individual islands may perhaps be taken independently, the cattle collected in small herds under fence, and by the sacrifice of a few the remainder of any herd that shows infection may be immunized, and the premises where they are confined disinfected until finally no more cases occur. But whatever method is adopted the seclusion of all within well fenced areas is the most important consideration. No nation has ever succeeded in extirpating this nor any other important infection in animals when they are allowed to run at large and mingle freely, herd with herd, on unfenced land.
PICTOU CATTLE DISEASE. HEPATIC CIRRHOSIS.
This is a fatal affection of cattle met with in the counties of Pictou and Antigonish, Nova Scotia, which seems to make a slow extension from farm to farm, but does not spread widely after the manner of a disease propagated by contagion alone, apart from other concurrent causes.
Alleged Causes. E. F. Thayer (1880) tells us that the inhabitants traced its origin to the arrival from Scotland, about 1853, of a ship in earth ballast, containing the seeds of the common ragweed of Europe (Ambrosia Artemisiæfolia), alleging that the trouble extended with the extension of this weed. This plant has a strong odor (it is known in Pictou as “Stinking Willie”), and, like other plants shedding an abundance of odoriferous pollen, has been charged with arousing “hay fever,” but though very common in Europe it has never been charged with producing anything like the Pictou cattle disease. The coincidence of the plant and the disease is manifestly a mere accident. Professor Lawson, of Halifax, investigated the flora of the district but was unable to find any poisonous plant to which the mortality could be attributed. D. McEachran tells us that many farms are covered with the ragweed, so that it is abundant in the hay, yet they are absolutely free from the disease.
The idea of a mineral poison must be dismissed in the same way. Pictou lies on the Silurian formation with abundant coal fields, and the chemical analyses made for McEachran were entirely fruitless of results.
Wyatt Johnston investigated the question of communicability by contagion from animal to animal, but he found that neither contact, nor inoculation produced positive results. Nothing positive has come of investigations into the possible microbiology of the disease. In blood from the jugular vein of a cow suffering from the disease, Thayer and McEachran found bacteria, under an object glass magnifying 600 diameters. Wyatt Johnston, “in a series of pretty exhaustive bacteriological examinations, in which all the tissues, including the blood, the spleen, the kidneys, lungs, and the fluids from the lymph glands” were employed, failed to find any constant or characteristic organism.
Attacks are very rare in winter, the disease usually appearing in the warm summer months, from June to August, and after the animals have been some time at pasture. This might lead to the suspicion of bacteria or other microbe on the growing vegetation; or of some insect enemy which, maturing at that season, transfers the poison from animal or other source to animal; or of some poison, vegetable or mineral, which acts injuriously on the liver, and which can only be had in the pasture. This, however, is mere hypothesis.
Liver affections are common in hot, damp seasons, but Pictou and Antigonish do not differ in climate from other counties in Nova Scotia, and much less do the infecting farms from those adjacent.
McEachran compares the disease to what occurs in the human being during famines, from the ingestion of innutritious and unsuitable agents especially deficient in albuminoids. The Pictou farmers, being nearly all fishermen, neglect the farms during the summer season, so that hay is only cut after the seeds have been shed, and when little nutritive matter is left in the stalks. Almost all the cases he saw were on such neglected farms. Wyatt Johnston, however, found it equally prevalent in overfed animals, so that hepatic disorder from either extreme seems to conduce to it. Again, if caused by lack of nutrition in the hay, winter, rather than summer, ought to be the season of attack and prevalence. Starvation and excess may both favor the attack, but the gradual extension from farm to farm, is strongly suggestive of the presence of a specific cause—probably a living organism.
The limitation of the disease to certain farms and even fields, and the cirrhotic condition of the liver remind one of the Schweinsberg disease of horses, and the lupinosis of sheep, in which the poison is evidently the product of cryptogamic or bacterial growth. With the damp, foggy climate of Nova Scotia, it would not be surprising if it should be ultimately shown that the source of the trouble is in a cryptogam which has as yet only invaded a given limited area. The winter immunity would be explainable on this basis. So also would be the statement of Wyatt Johnston that “When it attacks a new farm it affects chiefly animals that have been on the farm for two or three years. By the end of the second year it kills or attacks 10 per cent., and by the end of the third season it has practically involved all the old cattle which have been allowed to remain on the farm.” The hepatic disorder being a progressive one and probably due to the toxic products of fermentations carried on outside the animal body, a few only would show the morbid results at first, while later, with advancing structural changes in the liver, and an increase of the toxins that cause it, the number of sick animals would steadily increase.
Symptoms. The animal is at first dull and sluggish, with drooping head, lusterless eyes, staring coat, normal respiration and temperature, pulse often about 60 per minute, relaxed bowels and marked diminution of the milk secretion. The milk acquires a bitter taste and unpleasant odor. The pulse is usually full and soft, and the eyeballs may bulge visibly out of the sockets. The diarrhœa tends to encrease, the stools becoming liquid and black, yet in exceptional cases the bowels are confined for the first four or five days, or even permanently, appearing to be completely paretic. By the end of a week the abdomen becomes full and pendent with hollow flanks (pot bellied), or even rounded and tense, while manipulation and percussion show an abundant exudation into the peritoneal cavity. The pulse encreases in frequency (80) but the temperature is not elevated unless there is concurrent sepsis (Johnston). Thayer quotes an advanced case with a temperature of 105° F. He also notes obstinate standing, trembling of the muscles of the hind limbs, and complete suppression of appetite and milk secretion.
The disease is essentially chronic, often lasting a number of months. Many cases are doubtless slightly affected before external symptoms are manifested.
Lesions. If the disease has resulted in death there is usually marked emaciation, yet the abdomen is distended by accumulation of a clear yellowish fluid. From six to nine or more gallons may be present. The fat of the omentum, mesentery and sublumbar region has disappeared and the connective tissue is distended by a clear, amber-colored, watery fluid. The liver is the seat of marked changes. In the early stages it is congested and the gall ducts and bladder are filled to repletion with a thick, dark colored bile, which is further present in abundance in the intestines. In these early stages Johnston found cloudy swelling and opacity of the hepatic cells; somewhat later they had undergone distinct fatty degeneration. In the advanced stages, however, in animals that had been ill for two or three months, there was distinct fibrous degeneration, and compression and disappearance of the normal liver cells, in other words, a condition of marked cirrhosis, the result doubtless of the early congestion.
Johnston further notes the distension of the submucosa of the fourth stomach at intervals by a clear, viscid, liquid exudate, so that rounded swellings appear on the surface, and in some instances, after a month’s illness, distinct ulcers are shown upon the mucosa.
The lungs, pleuræ, pericardium and nervous system, are usually normal, unless in case of septic complication when petechiæ and circumscribed blood extravasations may be seen.
Text Book of Veterinary Medicine, Volume 4 (of 5) · The Wunder Library — complete classics, free to read, with narration.