820 Trichina Disease. 



For the certain recognition of trichinae, niicroseopic examination is essential. 

 According to Johue, this may lie undertaken in fine oat-grain-sized pieces of muscle 

 which, after the addition of water or common salt solution (O.T'/c), or acetic acid 

 (0.1 to O.o'/c), have been pressed together between two glass plates (the best form is 

 the socalled compressorium). Ten, or at most 40 to 50 diameters of magnification are 

 sufficient. By this means, free parasites or non-t-alcified capsules, enclosing young 

 trichina^, may be recognized very easily, while after calcification in a transparent 

 light only tlie black, characteristic lemon-shaped capsules are visible. After addi- 

 tion of dilute hydrochloric acid the lime salts dissolve out, whereupon the trichinie 

 inside the capsule, which has now become transparent, appear in view. For examina- 

 tion the above named muscles are best adapted. 



For scientific examination Tikhomiroff recommends the following procedure: 

 The small-cut pieces of muscle that are to be examined are for half an hour put 

 into a mixture of nitric acid (4 parts) and chloride of potassium (1 part), and 

 then carefully shaken in distilled water, whereby the muscle is made to separate into 

 fine fibres. Minute swellings may be perceived in the fibres with the naked eye; 

 under the microscope the eneapsuled trichinae may easily be seen. Close puts a small 

 piece of the suspected muscle in a conical glass containing a mixture of hydro- 

 chloric acid and pepsin. The separated trichinae sink to the bottom and can easily 

 be removed with the pipette. 



As additional anatomical changes one finds, before encap- 

 sulation, only hyperemia of the lung and parenclmiiatous de- 

 generation of the internal organs, further, acute intestinal ca- 

 tarrh and acute swelling of the mesenteric hmph glands, es- 

 pecially during the residence of trichinae in the intestine. 



Mature trichinae are found 4 to 6 weeks, at latest 8 weeks, after infection in 

 the anterior part of the small intestine, seldom in the large bowel. To discover these, 

 the intestinal contents are diluted with water when the trichina may be recognized 

 with the naked eye as very fine, short, whitish threads. Yet it is more suitable to 

 put a drop of the mixture between the slide and cover glass and examine it with 

 a magnification of 40 to 50 diameters. 



Symptoms. In living swine trichinosis has not yet been 

 diagnosed, although there is no doubt that after intensive in- 

 fection symptoms of disease arise, but these are ascri])ed to 

 other affections. The symptoms of trichinosis in s\\dne have 

 therefore been observed only after feeding experiments. 



The disease of the intestine mostly declares itself 3 or 4 

 days after infection, at the latest towards the end of the first 

 week. The animals suddenly become ailing, take no food, vomit 

 at times, crouch in the straw and move about unwillingly with 

 arched backs. Obstinate diarrhea is hardly ever absent ; at first 

 the feces are pultaceous, then watery and ill smelling, and the 

 animals also show sjonptoms of colic. After an extensive in- 

 fection the animals rapidly lose condition and sometimes die at 

 the end of the second week, in other cases the s^Tiiptoms of an 

 attack of muscular disease manifest themselves. 



The second stage generally sets in towards the end of the 

 second week, and in the meantime the animal rubs itself on 

 hard objects, moves about stiffly and later lies motionless in 

 one place with outstretched or bent extremities. Breathing be- 

 comes very painful and superficial. Huskiness also is seldom 

 absent. If the disease involves the muscles of mastication, 

 chewing is hindered, and occasionally total trismus may arise, 

 while the affection of the throat muscles causes difficulty in 



