456 Veterinary Medicine. 



Prevention. Every effort must be made to break the chains of 

 succession in the reproduction of the pinguicola. The presump- 

 tion is that the worm passes no part of its cycle of Hfe in any other 

 animal than the pig. There is no evidence of any other genus of 

 vertebrate or of invertebrate animals proving a host of the para- 

 site in its immature or mature condition. There is therefore no 

 need of any restriction with regard to other domesticated or wild 

 animals. 



Hogs should be excluded from all ground known to be infested, 

 or on which infested hogs have been, or which receives drainage 

 from fields, lots or pens occupied by other hogs ; also from water 

 derived from wells having leakage through a porous surface soil, 

 and from ponds, lakes or streams that are likely to bear the ova 

 of the pinguicola. If the parasite exists in the vicinity, the re- 

 striction of the water supply to deep wells, raised and closed at 

 the mouth, and cemented sufficiently far down to prevent all sur- 

 face drainage, or the boiling of all water supplied will be a most 

 important precaution. Above all, the pigs should be kept apart 

 from slaughter-houses, and streams into which they drain, and on 

 no account should they be allowed the offal or flesh of other pigs, 

 including .scraps from the kitchen, until such material has been 

 thoroughly cooked. The common feeding trough of the pig invites 

 infestment, since the animal can get in not only with his no.se but 

 also with his feet, filthy from direct contact with the urine and 

 faeces of himself and others. The trough should always have a 

 sloping cover, extending forward and upward at an angle of 45^ 

 from the posterior border, and which will at least exclude the feet 

 from the food. The trough should further be cleansed daily and 

 disinfected by a solution of salt, sulphuric acid or copperas. 



As in the case of other communicable disea,ses of pigs, the mass- 

 ing of these animals in large herds in the contaminated localities 

 is particularly dangerous, and their separation into small lots in 

 distinct enclosures, or better still, the seclu,sion of each pig in 

 its own pen will do much to prevent the propagation of the para- 

 site. If kept on paved or cemented floors only and scrupulously 

 clean, infestment will be largely obviated. 



Finally, purchased pigs should only be added to sound herds on 

 the basis of irrefragible evidence of the soundness of the herds 

 and locality from which they came, and even then only after quar- 

 antine. 



