. Annual report of the North Carolina Agricultural Experiment Station. THE PORK WORM- Trichina spiralis. This is a nematode worm,thread-like in form, taperingto the head. The length orthe mature worm is from A toJ- inch. The female bringsforth her young alive, insteadof in, the egg, as with mostother worms. In the larvalstate the worm is found doub-led up till it resembles theletter S, in cysts in the mus-cles of different flesh-eatingFemaie-nat- animais5 but with the greatest frequency in the rat, hog andhuman. The mature form are found only in the intestines, wherethey remain but a brief per
. Annual report of the North Carolina Agricultural Experiment Station. THE PORK WORM- Trichina spiralis. This is a nematode worm,thread-like in form, taperingto the head. The length orthe mature worm is from A toJ- inch. The female bringsforth her young alive, insteadof in, the egg, as with mostother worms. In the larvalstate the worm is found doub-led up till it resembles theletter S, in cysts in the mus-cles of different flesh-eatingFemaie-nat- animais5 but with the greatest frequency in the rat, hog andhuman. The mature form are found only in the intestines, wherethey remain but a brief period, just long enough to grow to maturityand propagate, which usually takes a week. The old worms then Figure 21.—Spine-headed worm,ural size. PARASITES OF DOMESTIC ANIMALS. 133. die and the young larvae emigrate to the striped muscles where theybecome encysted and remain dormant until they are taken into thestomach of some animal which eats the flesh which they in the stomach, the cyst or case dissolves and sets free theenclosed worm, which, in three or four days, grows to maturity, as already stated. A single ounce of infestedpork may contain as high as 300,000 encystedworms—sufficient to stock the animal whicheats it with 25,000,000 larvae. The larva maylive dormant in the cysts for from eight toeighteen months. At the end of the latterperiod the enclosed worms are usually dead andthe space filled with a deposit of lime. Hencepork two years old is usually entirely safe touse, even if eaten raw. The symptoms of intestinal infestation in thepig are, loss of appetite, thirst, grinding theteeth, and fever. The eyes have a peculiarglassy appearance, the back is arched, the tailuncurled, and there is more or less symptoms last until
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectagriculture, bookyear
