Page:Encyclopædia Britannica, Ninth Edition, v. 17.djvu/70

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58 MURRAIN one country to another, their concentration in markets, their incessant renewal, the mixing of native with foreign animals, a general indifference to the existence of con tagious diseases and the losses they might inflict, the absence of anything like an organization to control and regulate this movement, carry out sanitary regulations, and investigate and suppress these murrains all these have operated in rendering some of the most harassing and destructive scourges more or less cosmopolitan, spread ing them from a very limited area in the middle of a continent to every quarter of the globe, where they flourish as vigorously and persistently as if indigenous to the soil. The best-known murrains are discussed below. 1. Anthrax.. This is one of the most diffused and interesting of murrains, affecting, as it does, wild as well as domesticated animals. It prevails, in one or more of its forms, over the entire surface of the globe. It at times decimates the reindeer herds in Lapland and the Polar regions, and is only too well known in the tropics and in temperate latitudes. It has been observed and described in Russia, Siberia, Central Asia, China, Cochin China, Egypt, West Indies, Peru, Paraguay, Brazil, Mexico, and other parts of North and South America, in Australia, and on different parts of the African continent, while for other European countries the writings which have been published with regard to its nature, its peculiar character istics, and the injury it inflicts are innumerable. Countries in which are extensive marshes, or the subsoil of which is tenacious or impermeable, are usually those most frequently and seriously visited. Thus there are regions notorious for the prevalence of this murrain, such as the marshes of Sologne, Dombes, and Bresse in France ; certain parts of Germany, Hungary, and Poland ; in Spain it is severely felt in the half-submerged valleys and the maritime coasts of Catalonia, as well as in the Romagna and other marshy districts of Italy ; while it is epizootic, and even panzootic, in the swampy regions of Esthonia, Livonia, Courland, and especially of Siberia, where it is known as the Sibir- skaja jaswa (Siberian boil-plague), and where it sometimes happens that, in order to suppress its ravages, battalions of soldiers must be sent to bury or burn the carcases of infected animals which float in the canals or lie in the swamps, rendering the air and the water pestilent. The records of the anthrax go back to a very ancient date. It is supposed to be the murrain of Exodus. Classical writers allude to the anthrax as if it were the only cattle disease worthy of mention (see Virgil, Georg., iii.). It figures largely in the histories of the Early and Middle Ages as a devastating pestilence among animals, and through them to mankind ; and our oldest Anglo-Saxon manuscripts contain many fantastic recipes, leechdoms, charms, and incantations for the prevention or cure of the " blacan blezene " (black blain) and the relief of the " elf- shot " creatures. From these up to our own times it has attracted more and more attention, as even in the last and this century it has sometimes spread in an epizootic manner over the whole of Europe, from Siberia to France. It was in this malady that the presence of disease-producing germs (bacilli] was first discovered by Pollender and veteri nary surgeon Brauell of Dorpat, and their real character afterwards verified by Davaine ; and it has been in their experiments with this disease that Chauveau, Toussaint, and Pasteur have shown how to make the morbific poison its own antidote. Symptoms. These vary according as the disease runs its course as a general or localized affection. While death is usually rapid or sudden when the malady is general, constituting what is desig nated splenic apoplexy or anthrax fever, in the local form, marked by the formation of carbuncles before general infection occurs, it is more protracted. In the apoplectic form there is apparently no local manifestation, and dissolution may take place so quickly (in a few minutes) that there is no time to afford relief. One or more of the best-conditioned and perhaps robust animals in a herd or Hock, which until then exhibited no sign of the disease, are sud denly struck down as if shot while grazing, feeding in the stable, or travelling, and rise no more. Or they commence all at once to tremble and stagger ; the breathing becomes hurried and the pulse very rapid, while the heart beats violently ; the internal tempera ture of the body is high ; blood flows from the nose, mouth, and anus ; the visible mucous membranes are almost black in tint ; and death soon supervenes, being immediately preceded by delirium, convulsions, or coma. In some cases the animal rallies from a first attack, but soon a second ensues, to which it speedily succumbs, the creature in the interval remaining drowsy and showing mus cular tremors. In the carbuncular form the tumours may appear in any part of the body, being preceded or accompanied by fever. When the tongue is affected, the disease is usually known as blain of the tongue, tongue evil, or glossanthrax. The tumours or malignant pustules are developed in the sub cutaneous connective tissue, where this is loose and plentiful, in the interstices of the muscles, and in the lymphatic glands. In the various animals affected they have their special affinities for certain regions, as between the branches of the lower jaw, upper part of the throat, lower portion of the neck, breast, behind the shoulders, back, flank, substance of the tongue, &c. If the part where an anthrax tumour is about to appear is covered with hair, this will be observed to become erect, and if the hand is passed over the part perhaps a slight crepitation will be felt ; there is also increased sensibility. In many cases there soon appears a nodosity, simple or multiple, about the size of a small nut and circular or irregular in outline. Ordinarily this is little sensitive in itself, the pain the animal experiences being due to the increased sensibility of the surrounding parts. In other instances the tumour suddenly com mences in the appearance of a soft cedematous swelling, crepitating and undefined. When the eruption takes this form the tumours are quickly developed, and in a few hours invade all the neighbour ing parts, extending in every direction with equal rapidity, the skin covering them becoming tense and hard like parchment, and crackling on pressure. As they extend they become cold and in sensible, a variable number of phlyctsence arise on their surface, and these quickly bursting give issue to a serous irritant fluid. If an incision is made in the swelling at this stage there is no symptom of pain, and a black or reddish serum escapes, extremely foetid and corrosive, which produces a noise as it flows like the crackling of paper or the bubbling of boiling water. Sometimes passive haemor rhage ensues after the incision is made, and continues until death. In whatever form the tumours are developed, their course is always the same, being more rapid the earlier they appear. In from two to eight hours they attain a considerable size, and tlfe tissues mortify as they are invaded. As they are developed the animal seems to become relieved, the fever abates, and the more urgent symptoms vanish. But, when they have attained certain proportions, general symptoms are manifested, and these vary according as the malady is to terminate favourably or otherwise. In some rare instances the matter which constitutes the tumours is suddenly absorbed, abundant sweats, an increased flow of urine, or a serous foetid diarrhoea ensue, and the animal promptly recovers. In other cases, by surgical intervention, the evolution of the tumours is limited to a certain extent ; they reach the suppurative stage, and finally disappear. In ordinary circumstances, however, it happens that after the interval which follows the eruption, the organism being incapable of eliminating the morbid element, the tumours vanish ; but this is only a transference, for the disease assumes all the grave characters of anthrax fever without local manifestations, the general symptoms reappear, and, running their course with marvellous rapidity, the animal perishes in a few hours. A form of anthrax affects the horse more especially, and this by some authors has been designated anthrax typhus. It manifests itself locally and generally, and is very fatal (Fleming, Veterinary Sanitary Science and Police, vol. ii. p. 122). In cattle there is a disease very fatal among young stock, and known to breeders and graziers by various names, the most com mon of which is "black quarter," which had always been classed among the forms of anthrax until its nature was investigated by Arloing and Cornuvin, who have termed it symptomatic anthrax (Charbon symptomatique), while by others it has been named anthra- coid erysipelas, &c. This is at first a local disease, affecting usually one hind quarter, and occurring among young animals more espe cially, particularly those fed on rich food and thriving rapidly. It also occurs very suddenly, runs its course in a very brief space, and nearly always terminates fatally unless surgical and medical treat ment is promptly resorted to. It is caused also by a bacillus or bacterium somewhat different from that of ordinary anthrax. In splenic fever or splenic apoplexy, the most marked alterations observed after death are the effects of rapid decomposition, evidenced by the foul odour, disengagement of gas beneath the skin and in the tissues and cavities of the body, yellow or yellowish- red gelatinous exudation into and between the muscles, effusion