CHAPTER XXXI 



MANAGEMENT OF SHEEP (CONTINUED) 

 INTERNAL PARASITES 



Internal Parasites Two classes of worms Cestode and Nematode 

 Tape-worm producing Gid Liver-fluke producing Rot Strongylus 

 producing Husk or Hoose Sheep Bot Fly producing Bots in the 

 Head. 



T NTERN AL Parasites. There are two classes of worms 

 A of which the intestines of domestic animals are the 

 habitat, namely the cestode or tape-worms and the nematode 

 or round worms. The former require an intermediate host 

 or " bearer " to complete the cycle of their life-history, but 

 the whole life period of the latter is completed in the one 

 host. 



"Three Cestode worms are found in ruminants Tania 

 expansa, T. denticulate*, and T. alba. The first is the largest 

 tape-worm known, reaching a length of 40 feet. T. den- 

 ticulata is only about 18 inches, and T. alba about 9 feet 

 long ; all are unarmed, so they cannot attach themselves to 

 the walls of the intestine, and are therefore easily expelled 

 by a simple purgative ; they are not common in Britain, and 

 cause little functional derangement ; but on the Continent, 

 in Australia and in America, attacks of T. expansa have 

 assumed an epidemic form, producing diarrhoea and emacia- 

 tion, especially in lambs. T. expansa is also found in this 

 country associated with nematode worms in the stomach 

 and intestines of sheep, generally of the species Strongylus 

 contortus? a wire- worm about \ to \ of an inch in length, 2 



1 Young Cattle also suffer from the attack of a nematode worm 

 similar to Strongylus contortus, but larger ; these worms fix themselves to 

 the walls of the abomasum, or fourth stomach, and produce similar 

 effects to those seen in sheep, and the treatment is the same as for sheep. 

 Cysticercus bouts is the hydatid form of the Tcenia mediacannulata of 

 man. This cystic form is found in the muscle and connective tissue of 

 cattle, and gives rise to what is known as "measly beef." 



2 Described and illustrated at pp. 385-8 of the Author's Farming 

 Industries of Cape Colony. 



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