204 PARASITES OF THE, DOMESTIC ANIMALS . 



"Ransom's investigations showed that under careful inspection the 

 percentage of affected sheep in this country has amounted to two per 

 cent, or more, and that approximately twenty thousand sheep carcasses 

 were retained in 1912 ia abattoirs under Federal inspection on account 

 of sheep measles due to this parasite. 



"The bladder worm, Cysticercus ovis, in the meat of sheep is oval and 

 ranges in size from about one-third of a centimeter (one-eighth of an 

 inch) to almost a centimeter (three-eighths of an inch) in length. Inside 

 of this bladder there is a single tapeworm head, in which respect, as well 

 as in size, this cysticercus differs from a hydatid or a coenurus. Numer- 

 ous cysts, however, may be scattered through the musculature, so that 

 in their numbers there is a compensation, so to speak, for their small 

 size and lack of multiplicity of heads. Inasmuch as the presence of these 

 cysts calls for condemnation of a part or all of the infested carcass, ac- 

 cording to the degree of the infestation, and the number of carcasses 

 amoimts to twenty thousand a year, this parasite has considerable 

 economic interest for this country, and never more than at the present 

 time when the "high cost of living" is such a vital topic. 



"When one of these cysticerci from mutton is ingested by a dog, the 

 tapeworm head passes undigested to the dog's intestine and develops 

 into a fairly large tapeworm, comparable to the gid tapeworm. Sim- 

 ilarly, this tapeworm, Tmnia ovis, produces eggs which are passed 

 out with the feces of the dog, and which are ingested by sheep as 

 they graze over range or pasture or drink water contaminated by these 

 feces. 



"The parasite has been found in Europe, Africa, and New Zealand. 

 It has been found thus far in seven States in this country. It appears 

 to be particularly prevalent in the West, a fact that is possibly related 

 to carelessness on the part of the western sheepmen as regards disposal 

 of carcasses of sheep djdng on the range." 



Control. — Measures of prevention consist in restraining dogs from 

 access to the flesh of affected sheep unless it is rendered non-infective 

 by cooking. Homeless dogs should be destroyed, and others going 

 about where their excrement may contaminate the food and water of 

 sheep should be kept free from tapeworms as a precuation, not only 

 against this, but other tapeworm larvse infesting sheep. 



CcENUROsis, Gid 



Gid, turnsick, or staggers are popular terms applied to a disease of 

 the brain or spinal cord, caused by the presence in these locations of 

 the gid parasite Multiceps multiceps {Coenurus cerehralis), the coenurus 

 or larval stage of the tapeworm of the dog Multiceps multiceps, Fig. 113 

 (p. 179). 



