432 Veterinary Medicine. 



meats, scraps and swill, from the excreta and flesh of each other, 

 and from other sources, so that if trichinosis exists in the neigh- 

 borhood they become infested and infest the pigs in their turn. 



3. When hogs are fed on the offal of abattoirs, it should be at 

 a distance from the latter and the slaughter-house products 

 should have been subjected to prolonged boiling and carried 

 to the hog pens in vessels which have also been just subjected to 

 a boiling temperature. 



4. Kitchen scraps and swill should also be thoroughly 

 boiled before moving them to the pig pen. If taken to the 

 pen raw there will be many loopholes for diffusion of trichinae 

 and especially through rats and other vermin, in which the worms 

 rapidly multiply. If the meats are first cut into pieces of three 

 inches in diameter, the boiling may be implicitly relied on. 



5. Hog pens, yards or pastures should not be allowed on 

 streams (especially small or sluggish ones) that have received 

 the drainage of ground or pens occupied by other hogs, of 

 slaughter-houses, rendering works, sewers or privies. 



6. Hogs must be prevented from running at large on un- 

 fenced grounds, highways, commons, or any place where they 

 can find human excrement. 



7. All carcases of hogs, not destined for human food should 

 be promptly burned, dissolved in acids or subjected to pro- 

 longed boiling (better if superheated as in rendering). Dead 

 rats, mice and other vermin should be similarly treated. 



Prevention in Man. The foundation of radical prevention 

 of trichinosis in man rests on the extermination of the worm in 

 the pig. Until that can be done other measures of protection 

 must be maintained for the human race. 



I. Thoroughly cook all flesh that is to be eaten. It has 

 been shown that epidemics of trichinosis occur chiefly in persons 

 who eat pork underdone, and hence the frequency "of such out- 

 breaks in Northern Germany and in German families in America 

 and their rarity in Belgium, France, England and America. The 

 thoroughness of the cooking is the main question and the experi- 

 ments of Colin especially throw definite light on this question. 

 A mass of trichiuous flesh weighing four pounds subjected to 

 active boiling for an hour and a half and then fed to a dog and a 

 brown rat produced no living trichina in their intestine. A sec- 



