PREVENTION OF VEEMICEOUS DISEASES. 509 



can be destroyed by tracheal injections of camphor and creosote ; 

 but as skilled labour has to be employed, and then only one of the 

 three worms in the lamb is affected, the method is scarcely to be 

 advised, in sheep. Fumigations with sulphur, &c., are equally un- 

 satisfactory. All we can do is to keep the stock well fed, isolate 

 the aflfected ones, and avoid foul pastures. In gapes, however, 

 allowing a drop of camphorated or eucalyptus oil to run down 

 the trachea is always satisfactory, and perhaps is the best way to 

 treat birds when only a few are attacked ; but when large numbers 

 have gapes the use of the fumigating-box is advisable. Blowing 

 into the box, with bellows, finely ground camphor and chalk causes 

 the worms to relax their hold and the birds to cough, and so the 

 nematodes are expectorated. 



Plukes or trematodes are impossible to destroy, as far as our 

 present knowledge goes, when once fairly housed in the bile-ducts 

 and liver. Land along the edges of rivers and streams may be said 

 to be generally liable to be infested with trematode germs, which, 

 as pointed out previously, live in the water-snails {Liinn<eus trun- 

 eatulus) during part of their early life. Certain meadows in which 

 these molluscs abound are sure to affect the flock ; such land 

 should thus be fed to beasts which, although sometimes subject 

 to trematodes, are not seriously affected. Attention should be 

 paid to the moUuscan hosts, hordes of which may be destroyed, 

 when cleaning out the . ditches and dykes, by casting lime over the 

 mud brought out, when not only the primary host but the embryo 

 flukes are killed. In all parasitic vermiceous diseases the strength 

 of the host must be well maintained by good and rich feeding, so 

 that the invaded animal can withstand the extra drain on its 

 system. This and proper sanitary measures, the application of a 

 few well-known vermifuges, and the de,struction of diseased parts 

 instead of giving them to dogs and other animals, are the main 

 points in preventing the too persistent losses from vermiceous 

 diseases. 



In the case of infected food, which seldom now passes out of the 

 markets in this country, thorough cooking destroys the cysts and 

 germs of various diseases, the chances of infection being very slight. 

 Water plays a prominent part in the distribution of these com- 

 plaints, and where possible the purest spring- water only should be 

 employed, for stock as well as for man, especially during and after 

 an outbreak. 



