454 Veterinary Medicine. 



Cysts. The cysts vary in size and are often collected in groups, 

 each cyst usually containing two worms, a male and female ; less 

 frequently a male and two females, or a female and two males, 

 and still more rarely, four or five worms in a single cyst. Beside 

 the worms the cyst contains a quantity of purulent debris, includ- 

 ing multitudes of ova. In old cysts the parent worms may have 

 died and disintegrated, leaving only the ova. I/Utz has observed 

 peritoneal effusions and fistulous indurations in connection with 

 the encysted worms in the vicinity of the kidneys. 



Fletcher found that when the worms were very numerous in 

 the liver and when general disorders had set in there were exten- 

 sive hepatic congestion and softening. To the ravages of the 

 worm he attributed a destructive epizootic which went by the 

 name of hog cholera. In these cases it is difficult to e.stimate, 

 from the description, the relative causative importance of the en- 

 cysted hepatic parasites on the one hand, and of a possible coinci- 

 dent hog cholera infection on the other. Hepatic derangement 

 might well cause portal congestion, intestinal catarrh, indiges- 

 tions, fermentations, and dysenteric disorder, to say nothing of 

 metabolic or microbian toxic products in the liver. The case 

 may be fairly compared to outbreaks of alleged hog cholera, 

 which were found to be associated with multitudes of intestinal 

 worms, and in which the free administration of tobacco led to a 

 cure. With our present light it is important to bear in mind 

 that the stephanurus may enter and encyst itself in the liver, in 

 large numbers, producing symptoms that resemble those of acute 

 congestive affections of that organ. Also that secondary ga.stro- 

 intestinal disorders, easily mistaken for hog cholera, may result. 

 On the other hand we should bear in mind that Fletcher found 

 the parasite in nine out of ten pigs killed in the Indianapolis abat- 

 toirs, although the animals had shown no sign of illness, being in 

 fine condition, and killed for packing. 



Pig breeders in America have been in the habit of attributing 

 all cases of weakness, stiffness, and paralysis of the hind limbs in 

 swine, to this kidney worm, but there can be no doubt that this 

 wide generalization is usually erroneous. Rheumatism, sprained 

 back, rickets, intestinal disorders, causing sympathetic nervous 

 atony, disordered innervation as the result of poisoning of the 

 nerve centres by toxins produced by fermentations in the swill or 



