PARASITES OF ANIMALS. 333 



petite fails, the animal leaves its fellows and may be found in 

 a corner of the pasturage or under a tree, its skin covered 

 with vermin and flies, which it no longer has the vigor to 

 brush off. The patient finally dies in a state of extreme 

 weakness. 



Worms in the bowels often form a serious complication, 

 though one too much overlooked. From the presence of 

 these arise indigestions, tympany (bloating), and above all, 

 diarrhoea, which rapidly exhaust the strength and hasten 

 death. 



The parasites found in the intestines of oxen in sucli cases 

 are chiefly : the Strongylus radiatus, in the small intestines, 

 and the Tricocephalus affinis and occasionally the Sclerosto- 

 mum hypostomum in the larger intestines. These are merely 

 the common parasites of the ox, which increase in direct ratio 

 with the debility and the improper condition of the aliments. 

 The same holds good in the horse and ass. In similar condi- 

 tions their small intestines contain the Ascaris megalocepliala, 

 and their large intestines the Sclerostomum equinum, the S. 

 tetracanthum and the Oxyuris curvula. To describe these 

 worms at length would unnecessarily extend this paper, and 

 serve no good purpose. 



Duration. — In ordinary cases, calves will live two or three 

 months after being attacked, although the blocking up of the 

 windpipe or principal bronchial tubes by pellets of worms, 

 or the accumulation in the lungs of ova and embryos to the 

 extent of causing a general inflammation, may at anytime pre- 

 cipitate death. Mr. Swift's calves died at periods of from 

 nine to fifteen days after they were noticed to be ill.' 



j» 



'■'■ Prevention. — Two indications present themselves as calcu- 

 lated to prevent this disease : — 1st. To prevent the worms 

 from gaining access to the system ; and 2d. To bring the an- 

 imal into a condition unfavorable to the development and 

 destructive work of the worms. 



Under the first head might be mentioned many specific pre- 

 cautions : 1st. In localities where the parasite is known to 

 exist, lambs or calves should not be depastured on land recently 



