DISEASES OF SWINE 533 



LUNG FLUKE. 



The lung fluke, Paragonimus Westermanii, is sometimes found 

 encysted in the lungs of hogs killed in the abattoir. Dr. A. J. Payne, 

 chief inspector in charge at Cincinnati during the latter part of 

 1898, found 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 flukes in American 

 swine are 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, but beyond this nothing positive has 'been demonstrat- 

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

 (Ind. B. 100.) 



MEASLES. 



Measles of the pig is a parasitic disease caused by the Cysti- 

 cercus cellulosse. Rud, a larval form of the Taenia solium, a tape- 

 worm sometimes found in man. The frequency of measles corres- 

 ponds with that of the tapeworm, as the pig becomes infected by 

 eating human excrements which contain segments of this parasite. 

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

 especially in the region of the abdomen, in the tongue, heart, neck, 

 shoulders, 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 spot 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 are passed out 

 with the faeces. These contain a large number of eggs and on 

 reaching the stomach are freed from their shells by the dissolving 

 action of the gastric juice. The embryo 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 as the head of a pin, 

 and in sixty days it has grown to about the size of a pea. It is then 

 enclosed in connective tissue and has fully developed, and at the end 

 of this period a well formed neck can be seen. Degenerative changes 

 take place quite early. The connective tissue capsule becomes infil- 

 trated with lime salts, and gradually the whole parasite undergoes a 

 calcareous degeneration. 



Symptoms. There are no definite symptoms. Some inves- 

 tigators have described as symptoms of measles, a hoarse voice, fall- 

 ing out of the hair, depression, loss of appetite, weakness, emacia- 

 tion, a partial paralysis, diarrhoea and oedematous swellings in the 

 region of the head, neck and shoulders. A more positive diagnosis 

 may be made by examining the visible mucous membrane of the 

 mouth, especially in the region of the tongue, for the characteristic 



