Page:The New International Encyclopædia 1st ed. v. 04.djvu/414

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CATTLE PLAGUE. 352 CATTLE PLAGUE. Causes. Faulty hygiene, by lowerin;; vitality, probably renders animals more prone to the at- tack aiid less able to bear up against it. Like hydrophobia, smallpox, or syphilis, it is devel- oped only by special virus. This virus occurs abundantly in the blood of every plague-stricken Ix-a-st. in the discharge from its nostrils, mouth, or eyes, in the otT-scouring;* from the bowels, probably even in the breath. It may be trans- ferred to healthy beasts by inoculation. A little of the blood or iiasal or other mucous discharges of a ]ilague case, if introduced underneath the skin of a healthy cow, develops the disease with- in a few days. The transference of the virus or contagion from the sick to the sound animal is not always so direct and evident. As with other contagious diseases, the virus may be car- ried considerable distances in the air ; it may ad- here to the food that has lain before infected beasts: to the litter from the stalls, or even after it has been heaped for weeks ; to the clothes of attendants: to the floors, walls, or sUiUing of buildings; or to imperfectly cleansed cattle- cars. It may gain access to the blood probably through the air-passages, perhaps also by ab- sorption through the mucous surface of the bowels, or even through the skin. Symptoms. In from three to six days after an animal has been exposed to the virus of cattle plague, or from 36 to 48 hours after being purposely inoculated, the temperature of the bodv is raised several degrees. A delicate thermometer introduced into the vagina or rec- tum, instead of marking about 101° V., indi- cates 104° to 10()°. Two or three days later a striking dullness is manifested, and the animal becomes indifferent to surroundings. The pdpils of the eyes are contracted, and the animal may be in a state of vertigo or coma. Within 12 to 24 hours the milk-secretion is diminished by one-half or two-thirds, the mucous membrane of the mouth is generally observed to be slightly reddened, and soon a granular, yellowish-white eruption, consisting of thickened epithelium cells and granules, appears on the gums round the incisor teeth, and by and by on the lips and dental pad. Some hours later the same erup- tion extends to the cheeks, tongue, and hard palate. Within 48 hours a crust of epithelium covers the gums, lips, and mouth, and then, wiped away or accidentally rubbed off, leaves the abraded membrane red and vascular and ex- hibiting patches of erosion. Tlie membrane lin- ing the vagina indicates verj' similar appear- ances ; it is reddened and vascular, dotted with grayish, translucent elevations about the size of rape-seeds, covered with a whitish-yellow, usu- ally sticky discharge, and occasionally marked with patches of excoriation. The skin is dry; there is hence a perverted development of scarf- skin, and of the oleaginous secretion of the irri- tated sebaceous glands. The skin is thus invest- ed with yellowish .scales; while on its thinner portions— about the lips, between the thighs, and on the udder — there are inqiular eruptions or elevations. The animal hangs its head, arches its back, the eyes are leaden and watery, and fi-om both eyes "and nose there latterly comes a dirty, slimy discharge. Appetite and rumina- tion are irregular. The breathing is oppressed; expiration is prolonged and accompanied by a peciiliar grunt. The pulse is small and thready, and is quickened as death ajjproaches. The bowels, usually confined at first, l)ecome, toward the sixth or seventh <lay, nnich relaxed; the discharges passed, often with pain and strain- ing, are profuse and liquid, offensive, acrid, pale- colored, and occasionally mixed with blood. Tlie patient loses weight and strength, totters if it attempts to walk, and luefcrs to lie rather than to stand. Death usually occurs within from two to seven days, and is preceded by muscular twitehings, a i)eeuliar, offensive smell, a cold, clammy state of body, moaning, grinding of the teeth, and rapidly increasing prostration. Prognosis. Cases usually terminate unfavor- ably when the animal's temperature falls rapid- ly; the pulse becomes small, quick, and weak; the breathing more difficult, distressed, and moan- ing; the diarrha?a increased, and the depression more notable. A more favor:iblc termination may be anticipated when, after the fifth day, the heightened temperature, so notable even from the earUcst stages, abates gradually; the breathing becomes cosier, the pulse finncr, the visible mucous membranes appear healthier, and patches of extravasation or erosion speedily disajipear. Sheep do not take rinderpest spimtaneously, and even when kejjt with diseased cattle, or in- oculated with cattle-plague virus, they do not catch the disease so certainly as do cattle. hen diseased, they exhibit, however, very similar .s-mptoms; but Professor Riill and ether observers" record that upward of 40 per cent, recover. C4oats, deer, anteloj)es. gazelles, yaks, and, indeed, all animals taking rinderpest ex- hibit with tolerable uniformity the same char- acteristic symptoms. Post-mortem Appearances. The mucous mem- branes are generally deeper-colored than nat- ural, are congested, softened, marked in places with the same granular patches discoverable during life within the mouth of the vagina, and in bad eases exhibit ledema. hemorrhage, and sloughing. The first three stomachs sometimes contain a good deal of food, but show less de- clensicm from health than does the fourth stom- ach, the mucous membrane of w'hieh is dotted with spots of congestion and extravasation. The coats of the bowels arc thinned and easily torn. The mucous coat, especially toward the middle of the small intestine, the opening into the ca-cum and posterior half of the rectum, is much congested, bai-ed of epithelium, and sometimes marked with blood-spots, but never ulcerated. Peyer's glands, so generally inflamed in the somewhat analogous typhoid feer of man, are l)erfectly healthy. The liver is yellow, and the gall-l)lailder contains an abundance of fluid. The respiratory mucous membrane, like the di- gestive, is vascular, and marked with submucous hemorrhage; the lungs are generally emphyse- matous, the heart often nuirked with blood- sjiots. The urino-genital, like the other mucous membranes, is congested in females, esi)eeially toward the lower i>art of the vagina and vulva; tlu- kidneys are enlarged and hemorrhagic in the cortical zone; the serous membranes and nervous centres are perfectly unchanged. As in other septicemic diseases," a considerable increase in the number of white blood-corpuscles is ob- served. The blood itself is dark in color; in the later stages it contains less water, probably owing to the draining diarrhiea, and about