810 i;(>Ai;i) or .\(ii(i( ri.riin:. 



Li'suMis mikI Syiii|'I«'iiis.— Tlu'S*' iiic <lirc<lly dfiMiitli'iit mi iln- presence 

 of the rtukc in .the liody. aud as llie liver is tiie (irit^aii yeiK'raily affected 

 and tlie chief abode of the parasite, the princiiial h'sions are in this orjran. 

 The rtutces aie contined to tlie yall duets, but inaj- pass out into tlie pioper 

 tissue of llic liver. Tliere is a catarrhal intlaniniation of the bile ducts. 

 The smaller ones beeoiue dilated aud form cysts. The inflammatory proc- 

 esses extend from the duets to the connective tissues of the liver ami it 

 becomes hypertroiilii«'d. The livei' cells are destro.ved to some extent. 

 dei)endinjr on the amount of infection, and a larce portion of the liver is 

 a mass of cicatricial tissue. The gall is changed in character, is less 

 thick, greenish brown or dirt.v red in color and contain liver cells, blood 

 V cells, etc. 



The Lung Fluke.— The lung fluke, paragonimus westermauii, is some- 

 times found incisted in the lungs of hogs killed in the abattoir. Dr. A. J. 

 Payne, chief inspector in charge at Cincinnati, found in the latter part of 

 1898 one per cent, of the hogs killed in the abattoir affected with this 

 parasite. The hogs were in good condition and only a few cysts were 

 found in each lung. The muscle fluke in American swine is probably 

 young specimens of the lung fluke. 



Its complete life history has not yet been determined, but according 

 to present knowledge the worm does not develop until after it leaves the 

 . host in the sputum. Some observers have succeeded in raising the em- 

 bryonic stage, l)ut beyond this nothing positive has been demonstrated. 

 This worm has been found in man, cat. dog, tiger and hog. 



Pork Measles.— Measles of the pig is a parasitic disease caused by the 

 Cysticercus cellulosae, a larval form of the Taenia solium, a tapeworm 

 sometimes foiuid in man. The frequency of measles corresponds Avith that 

 of tapeworm, as the pig becomes infected by eating Inunan excrements 

 which contain segments of this parasite. 



The bladder worms, or cysticerci, are found in the muscular tissue, 

 especiajly in the region of the abdomen, in the tongue, heart, neck, shoul- 

 ders, pelvis, flank and superior regions of the legs. They may be found in 

 other organs as well. The adult cysticerci represents a small vesicle 

 about the size of a pea or bean, of a dull white color and provided with a 

 head and neck. This is marked externally by a dark si)ot which is bent 

 in toward the inside of the vesicle. 



Method of Infection.— Man harbors the adult worm. Taenia Solium, and 

 hogs become infested with the larvae by taking into the digestive tract 

 the segments of the parasite that arc passed out with the faeces. These 

 contain a large number of eggs that on reaching the stomach are freed 

 from their shells by the dissolving action of the gastric juice. The em- 

 bryo is then free, perforates the intestinal wall, or enters a small blood 

 vessel and drifts along in the blood stream until it reaches a suitable 

 place to develop. Nine days after infection a small oval vesicle forms in 

 the infested tissues. In twenty days the bladder worm is about as large 



