14: THE DISEASES OF DOMESTIC ANIMALS. 



In fact, it may truly be said that they have been found infecting 

 pork in whatever land, and wherever they have been sought for. 



As to their presence in other animals than man and the hog, 

 they have only been unquestionably found in warm-blooded ani- 

 mals, such as cats, dogs, rabbits, rats, mice, the marmot, the wild 

 hog of Europe, and even the hippopotamus. 



Gerlach has produced invasion in calves and horses, while 

 Leisering w r as unable to in the latter animal. 



Several reports have been published with reference to the dis- 

 covery of trichinae in the flesh of fish and other cold-blooded ani- 

 mals, but they all fail of experimental proof, and are non-conforma- 

 ble with our knowledge of the physiological activities of the parasite, 

 which becomes torpid in a temperature a few degrees below that of 

 the ordinary living mammal. 



For some unknown reason they do not seem to be able to invade 

 the muscles of fowls, though some authors claim to have found 

 them in the intestines. A case is reported of invasion of some 

 soldiers from eating a goose (" Philadelphia Medical Times," April 

 13, 1878), the accuracy of which is very questionable, as pigs are 

 fully as easily stolen as geese; and no evidence exists that they 

 were seen in the flesh of the goose. 



With regard to hens, I made quite a series of experiments. 



1. I fed them with highly infected pork, in the natural way. 

 Eesults negative. !No trichinae, either in the intestines or mus- 

 cles. 



2. Assuming that the triturating powers of the gizzard might be 

 sufficient to destroy the parasites before they could gain access to 

 the intestines, I caused a quantity of infected pork to be chopped 

 for several hours, until it became a veritable mush; microscopic 

 examination of this mass revealed the presence of numerous free 

 trichinae. This mass was stirred up with warm water, so that it 

 could be drawn into a coarse syringe ; the intestines of the fowls 

 were then washed out as cleanly as possible with warm enemas, and 

 time given for the water to flow off again. Several syriugefuls of 

 the mass were then injected, and the outflow stopped artificially. 

 After forty-eight hours this obstruction was removed. Eesults 

 absolutely negative, so far as producing muscle-invasion was con- 

 cerned, at an examination made four weeks from the time of the 

 experiment. No trichinae in intestines. 



3. The abdominal cavity of six other fowls was opened, and two 

 tablespoonfuls of the watery mass, but thicker than the preceding, 

 poured in. The aperture was then sewed up. The hens drooped 



