TRICHIXIASIS OF MAN AND ANIMALS. 29 



diarrhoea, yet, in these animals, it was impossible to find any em- 

 bryos in their faeces. 



This by no means excludes the possibility of finding them in 

 other cases ; yet their passage away with the faeces must in a meas- 

 ure be retarded from their being buried in a profuse layer of mu- 

 cus, which is the product of the irritation caused by them. 



In none of these swine was it possible to discover anything 

 resembling the subcutaneous oedema which comes to pass in man 

 under the same circumstances, and which serves essentially to the 

 confirmation of the diagnosis. 



Leisering, of Dresden, has also made numerous experiments 

 with swine, of the same nature.* 



He says : " One can not speak of a trichin-disease in swine, 

 which is characterized by distinct and pathognomonic phenomena. 

 In this regard the trichinae deport themselves similarly to the cysti- 

 cerci, measles." 



Gerlach f says : 



a. " About two fifths of the hogs fed were either not affected 

 or but slightly indisposed ; the remaining three fifths were visibly 

 sick. 



b. " The light cases presented nothing of diagnostic value, while 

 in the severe ones the symptoms were of such a character that, 

 with the aid of the scalpel and microscope, a diagnosis could be 

 made." 



(This is no more than saying that, with diarrhoea and abdominal 

 pains, followed by disturbances in the motor functions, the scalpel 

 and microscope would reveal the true cause, if trichinae.) 



c. " After an attack of trichiniasis, the hog again becomes well, 

 and can be raised and fattened, as if nothing had happened. 



d. "In cases which apparently pass over symptomless, as the 

 animal betrays but slight constitutional disturbances, the infection 

 is still sufficient to make the flesh a dangerous article of food. 



e. " Hogs are most susceptible to trichin-invasion in early age. 

 Old hogs are not easily infected ; i. e., the muscles are not very 

 much invaded by the parasites. 



f. " Death results in over one half of the extremely severe cases. 



g. " Death is caused by means of intestinal irritation, as well as 

 the severe muscular disturbances. Forty-one per cent die by the 

 former, and fifty-nine by the latter." 



That trichinae can only gain entrance to an organism by means 

 of the mouth and alimentary canal is beyond all question. 

 * "Eericht u. d. veterinair Wesen im Sachsen," 18G2, p. 118. f " Die Trichinen." 



