148 TAENIA. 



Other parasites besides lice act as mediums and supply the conditions 

 favorable to transmission and propagation. 



The history of the development of tape-worm in a general way suggests 

 the manner in which they may be acquired. It is necessary that a living 

 embryo be first introduced into the stomach. This usually happens from 

 eating infested meat, which has not been sufficiently cooked to destroy 

 the embryos or render them incapable of further development. 



It is of interest to know that in certain countries, taenia with but rare 

 exceptions infests all the inhabitants, among whom raw cow's flesh is 

 looked upon as the greatest delicacy. In this instance both men and cattle 

 furnish the conditions favorable to propagation. 



Several varieties of tape-worm infest the canine race, and are found at 

 every period of life although most rarely among puppies. As regards 

 medical practice, the discrimination is of but little importance, the same 

 measures of treatment being alike applicable to all. 



The most common form is cucumerine ( Taenia Cucumerina) . This is a 

 delicate tape-worm which measures from ten to twenty inches in length. 

 The anterior portion of the body is like a thread, and the segments are 

 short but lengthen towards the tail. As they ripen the divisions between 

 the segments become more marked so that the worm presents a chain- 

 like appearance. They move about actively in the intestinal canal, and 

 are expelled with the feces or escape of themselves. 



The largest tape-worm found in the dog is the marginated, ( Taenia Mar- 

 ginata ) which may reach ten feet in length and the germ from which it is 

 propagated is derived from the sheep. 



Among certain sporting dogs the taenia serrata is the more common, and 

 the parasite from which it is developed is furnished by the hare and rab- 

 bit. This tape-worm varies from two to three feet in length. Many other 

 varieties exist, a study of which would be interesting but of little practi- 

 cal benefit. 



Symptoms . —The symptoms especially due to the presence of tape- 

 worm are but vague and indefinite. Disturbances of digestion, nutrition, 

 and of the nervous system occur, but in many instances are not suffi- 

 ciently prominent to clearly indicate the existence of taenia. 



When the appetite is voracious, and the animal seems strong, active, 

 and apparently in good health yet poor in flesh, if tonic treatment is em- 

 ployed and still the animal remains emaciated, then the presence of a 

 tape-worm should be strongly suspected, and the discharges from the 

 bowels carefully examined. The appearance of segments among the feces 

 will be of course conclusive evidence, and yet it must be remembered 

 that some are so small, others so delicate, they are casil y overlooked ; again 

 it is doubted if some forms of the parasites are expelled spontaneously. 



