218 



ZOOLOGY. 



in bad spirits; the tail straightens out, and they 

 often remain standing with bent limbs and arched 

 backs. There may be, in addition, pains in the 

 abdomen, diarrhcsa, and fever. Later on, when 

 the trichinae have settled down in the muscles, the 

 pigs suffer from stiffness in the legs and tenderness 

 in the loins ; they often cry out in pain. After this, 

 however, health and appetite may return, and they 

 can be fattened. Trichinous swine therefore appear 

 quite sound, and are slaughtered in due course. The 

 trichinae in the pig are found most abundantly in the 

 diaphragm, the masticatory, eye-, and other muscles 

 of the head, also in those of the neck, larynx, abdomen, 

 and loins. The fore part is more infested by trichinae 

 than the hinder part, but in very bad cases they are 

 found everywhere, even in the hams. Remedies : 

 (1) The swine must be prevented, as far as possible, 

 from taking up trichinae, and therefore must never 

 be given the offal from other slaughtered swine. 

 The flesh of trichinous swine should be burnt, and 

 not buried, lest dogs or other animals should eat it 

 and spread trichinosis. (2) Care must be taken that 

 no trichinous pork is eaten by human beings (micro- 

 scopic examination; meat inspection). Pork (or 

 sausages) must never be used raw or half cooked. 

 Trichina3 are killed by a temperature of 140° to 150° F. 

 The inside of the piece of meat must be exposed to 

 this temperature. 



Family : Filaridae {Slender Thread Worms). 



Elongated and thread-shaped. Round mouth. Do 

 not infest the gut or other cavities, but the tissues of 

 the body, chiefly connective tissue. None of the 

 species require notice here. 



Family : Ascaridse {Round Worms). 



Relatively shorter than the worms of the preceding 

 family. Mouth triangular, surrounded by three teat- 



