THE ANIMAL PARASITES OF CATTLE. 



535 



of several yards and to a breadth of three-fourths of an inch. Small 



portions of tapeworms, consisting of one or more segments, are 



occasionally seen in the droppings of infested cattle. The life history 



is not known, but the infectious stage is undoubtedly taken in with 



the food or Avater, infection being spread by the eggs of the parasite 



contained in the feces of infested animals. The eggs perhaps are 



swallowed by some small creature (an insect, worm, or snail) which 



acts as an intermediate 



host, and which when 



swallowed accidentally b}' 



a cow while grazing or 



drinking carries with it 



into the cow's stomach the 



infectious stage of the 



tapeworm. 



Adult cattle do not seem 

 to suffer much from in- 

 festation with tapeworms, 

 but in calves these para- 

 sites may cause scouring 

 and emaciation. 



Treatment for tape- 

 worms. — Medical treat- 

 ment for tapeworms in 

 cattle is usually unsatis- 

 factory, but the bluest one 

 treatment used for stom- 

 ach worms and mentioned 

 above (p. 533) may be 

 tried. Arsenic in doses of 

 1^ to 3 grains has been 

 claimed to give good re- 

 sults in the treatment of 

 calves for tapeworms. 



RoU:ND WORMS. 



Fir;. 23. — A tapeworm (Moniezia 

 infests cattle. 



ims'iima\ which 



A large roundworm 

 {Ascaris vitidoru7n) meas- 

 uring 6 to 12 inches in length sometimes found in the intestines of 

 cattle, especially calves, may cause inflammation and occasionally 

 rupture of the intestine. Infection occurs through the swallowing 

 of the eggs of the parasite in food or water which has been con- 

 taminated with the feces of infested cattle. 



A number of species of small roundworms, varying in size from an 

 eighth of an inch to an inch or more in length, occur in the intestines. 



