The Eggs and Larvae of Swine 
Parasites 
In view of the fact that one of the protozoan forms is very com¬ 
monly present in swine feces and may be mistaken for a parasite egg, 
this form is briefly noted here. It is Balantidium coli, one of the 
ciliates. In fresh feces it may be found actively moving about, in which 
case it will resemble the parasite as figured here (Fig. 17). In older 
feces it is found encysted and is then much more suggestive of a 
parasite egg. 
Tapeworms are rarely found in swine and can not be regarded as 
normally parasitic in this host. The few records we have of these 
Fig. 17. Balantidium coli. Enlarged. From Gedoelst, 1912, after Leuckart. 
worms from swine indicate, for the most part, that they are present as 
a result of the swine having eaten entrails of sheep or other animals, 
the swine being slaughtered shortly afterwards while the worms were 
yet present and undigested, or that the worms had developed in the 
swine but had failed to attain the normal development attained in the 
usual host, the worms being sterile. In view of this fact, the injunc¬ 
tions occasionally published by some writers, advising the feeding of 
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