370 DISEASES OF CATTLE, SHEEP, GOATS, ETC. 



Thin-necked bladder worms (Tsenia, Tiydatigena} are most 

 commonly found attached to the mesentery and omentum. There 

 is no medicinal treatment. 



TAPEWORM CYSTS IN THE MUSCLES, BEEF MEASLES. 



Small tapeworm cysts (Tsenia saginata) , about the size of a 

 pea, found in the muscles of cattle are the larvae of the common tape- 

 worm of man. Cattle become infected from feed or water which 

 has been contaminated by the feces of persons harboring the adult 

 tapeworms, and human beings in turn become infected by eating 

 raw or rare beef infested with the larval stage (measly beef) . 



To prevent cattle from becoming infested with this parasite 

 care should be taken that human feces are not placed where they 

 will contaminate the feed or drinking water. 



GID. 



Bladder worms (Multiceps socialis, or Coenurus cerebralis) 

 which are occasionally found in the brain of cattle, and cause gid, 

 turnsick, or staggers, deserve mention, as they are rather common 

 among sheep in the Northwest. As already alluded to, these worms 

 are the intermediate stage of a tapeworm found in dogs, and their 

 life history and the means of preventing infection have been briefly 

 discussed above. 



Cattle harboring this parasite show symptoms indicating an 

 affection of the brain, walking or turning in circles, dizziness, un- 

 even gait, impaired vision, etc. 



Treatment consists in trephining the skull and removing the 

 parasite, an operation which requires a skillful operator and is 

 frequently unsuccessful. Unless the parasite is removed affected 

 cattle almost invariably die. 



THREAD WORMS IN THE ABDOMINAL CAVITY. 



Thread worms (Filaria labiato papillosa) 2 to 4 inches long 

 are frequently found in the abdominal cavity. They seem to cause 

 little or no trouble. The embryos produced by these worms enter 

 the blood vessels. Stable flies while sucking blood take up these em- 

 bryos, which undergo a certain amount of development in the 

 body of the flies. These flies, again biting cattle, introduce the 

 partially developed worms with which they are infested into the 

 circulation, whence the worms migrate to the abdominal cavity 

 and there develop to maturity. The roundworms found occasion- 

 ally in the anterior chamber of the eye are perhaps immature 

 forms of this species which have reached this location during their 

 migration. 



LUNG WORMS. (See Verminous Bronchitis.) 



PARASITES OP THE BLOOD. 



A species of fluke (Schistosoma bovis) which lives in the blood 

 vessels (the large veins) of cattle in tropical and subtropical coun- 

 tries causes bloody urine, and a condition of the rectum somewhat 

 resembling piles. The embryos of Filaria labiato-papillosa which 

 occur in the blood may be found by microscopical examination. 

 They apparently cause no trouble. The organism \vhich causes 

 Texas fever is a protozoan parasite (Piroplasma bigeminup^) of 



