40 



SWINE 



PARASITES 



We find five or six varieties of worms 

 affecting swine, one of which has ah'cady 

 been described under bronchitis. The others 

 infest the stomach and intestinal canal. 



Probably the most harmful of parasites, 

 because it is communicated to man, with 

 oftentimes fatal results, is that known as 

 Trechinella Si:>iralis. This parasite may 

 affect practically all meat-eating animals. 

 If the flesh is infested the larvae are released 

 and find their way to the muscles where 

 they become lodged. During their migra- 

 tion from the stomach they cause severe 

 rheumatic pains. A man eating infested 

 pork which has not been properly cooked 

 becomes affected and in many cases 

 death follows. 



Pigs usually acquire the disease from 

 eating rats, or the flesh of another pig 

 which has died as a result of harboring the 

 worm. 



The symptoms are somewhat vague, but 

 we suspect the existence of these worms 

 when pigs show severe pains. They appar- 

 ently squeal and are uneasy for no cause, 

 frequently exhibiting pain when touched or 

 moved around. The parasite is not visible 

 to the naked eye, hence its presence may 

 not be diagnosed unless a search of the 

 muscles are made for the worm with the aid 

 of a microscope. 



Thorough cooking destroys the worm, 

 which therefore suggests the method of 

 prevention in the human. 



Another parasite which infests man is 

 also acquired from the pig. In the pig we 

 have the immature worm, known as 

 cysticercus or measly pork. Its presence 

 is manifested by small milky like bladders 

 about the size of tapioca, which may be seen 



THE COMMON ROUND WORM OF SWINE 

 (A Scaris Suum) a, Male; b, Female. 



on the heart and sometimes in the muscles. 

 These small bladders contain the head of 

 the parasite. When the partly cooked meat 

 is eaten by man the juices of the stomach 

 release the worm which immediately begins 

 to grow, adding a small segment at a time 

 to its body until it reaches a considerable 

 length. 



Man is the host of two tapeworms, the 

 one just mentioned acquired from eating 

 pork and the other from cattle. The mani- 

 festations in the pig are similar to those of 

 cattle and the life history is the same. 

 Cattle and swine take up the eggs of the 

 tapeworm passed by man. The larvae find 

 their resting place in the animals where they 

 remain immature and can only attain their 

 full growth when taken into the system of 

 human beings- Thorough cooking of all 

 meats is essential to human health. 



A GROUP OF CHESTER WHITE PIGS 



