144 



VETERINARY STUDIES 



is adult in the dog. A common adult tapeworm of the human, 

 has its larval or cyst stage in the flesh of the hog, causing what 



is called "measly pork." 



The adult tapeworm constantly 

 forms new segments back of the 

 small head. These segments ma- 

 ture while new segments are being 

 added in front of them. The 

 terminal segments, filled with eggs, 

 separate and pass off with the 

 manure, while the head remains 

 attached to the mucous membrane 

 and continues to produce new 

 segments. 



The injury to the host may be 

 great or slight depending on the 

 location — usually in the intestine 

 — and number of worms. The 

 worms may impair intestinal 

 (capacity and function by mere 

 I)resence in large numbers. They 

 may enter bile ducts and cause 

 serious trouble. Some species have 

 heads armed Avith hooks which 

 irritate the intestine and thus im- 

 pair digestion and absorption. 

 They may produce and free to the 



Fig. 49. — A Common Tapeworm 



OF Sheep (Curtice.) 



Taenia expansa, 



1, Hjead and neck; A, A, 

 suckers; B, B, folds in neck; 

 C, C, first segments. 



2. Head and body, showing 

 segments. A, head. 



intestinal contents, toxins or poi- 

 sons. The cyst stage may seriously disturb the invaded host 

 organ, e.g., the brain as in gid. 



Treatment ^ can be useful only when given before weakness 

 begins. Preparation for treatment is most important. Allow 

 no dry bulky food for several days. Fast 12 to 24 hours, depend- 

 ing on age and previous feed. Then give 1 to 2 drams freshly 

 ground areca nut in a small feed such as damp bran, or in a 

 small quantity of thin sirup, so that each sheep gets its proper 

 dose. Copper sulphate used as for stomach worms (see Lee- 

 ture XXX) is also a satisfactory treatment, and may be used 

 for both parasites at the same time. Follow this treatment in 

 3 or 4 hours by a physic. 



^ For sheep. Dose varies greatly with age and weight. 



