. The external and internal parasites of [man and] domestic animals. rane ofthe intestine, particularly in the coecum and colon, but some-times in ihQ small intestine and duodenum, and even in thepancreas. At the points where it adheres it Figure S3,causes small, dark-colored, raised spots. Theysometimes occur in vast numbers in the largeintestine, completely covering the surface;the number sometimes amounting, it is said,to a million or more. Ordinarily, however,these parasites, when lodged in the intestines,do not appear to produce any marked dis-ease or notable symptoms, although when ingre
. The external and internal parasites of [man and] domestic animals. rane ofthe intestine, particularly in the coecum and colon, but some-times in ihQ small intestine and duodenum, and even in thepancreas. At the points where it adheres it Figure S3,causes small, dark-colored, raised spots. Theysometimes occur in vast numbers in the largeintestine, completely covering the surface;the number sometimes amounting, it is said,to a million or more. Ordinarily, however,these parasites, when lodged in the intestines,do not appear to produce any marked dis-ease or notable symptoms, although when ingreat numbers, there can be no doubt butthat they must cause some inflammation andpain. More serious results, sometimes prov-ing fatal, happen when the worms enter theblood-vessels. They produce large aneurisms or dilations ofthe arteries, chiefly in the anterior mesenteric artery, but Figure 83.—Sclerostoma equinum, female, natural size; and anterior portion en-larged ; a, mouth; b, circle of hooks; c, o-sophagus; d, intestine; e, reproductiveorgans. From PARASITES OF ANIMALS. 137 also in the arteries of the colon, coecum, small intestine, andliver, as well as in the posterior mesenteric and renal arteries,and others adjacent to the intestine. These tumors are gen-erally fusiform, and as large as a mans finger; but they aresometimes globular, and may become as large as a manshead. The middle meml^rane of the artery in these dilationsbecomes enormously thickened, sometimes being twelve timesas thick as in the healthy artery. In old tumors various hardor calcareous deposits often take place in the thickened wallsor in the inner membrane; and in such cases, the walls beingweakened, are liable to be ruptured by some unusual exertionof the animal, when death results almost instantly. In theinterior of the aneurism there is generally a deposit of fibrin,firmly adherent to the inner surface. In this and in the dif-ferent layers of the walls the worms are found, — sometimes
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectparasit, bookyear1870
