208 



Treatment is in line of prevention only. Clean, 

 pure fresh water, free of the eggs or the parasites, 

 is necessary if the trouble is to be eradicated. The 

 old ponds, ordinarily filled with stagnant water, 

 should be drained. They harbor many bad para- 

 sites, and their harm is far beyond their value. 

 When water for sheep and cattle is taken from pure 

 streams or wells the trouble from liver flukes and 

 other parasites is reduced to a minimurr 



LOCKJAW. — This disease, very frequently called 

 tetanus, is an infectious disease in which the body 

 muscles are spasmodically contracted or stiffened. 

 The muscles that move the jaw are frequently af- 

 fected and the animal is unable to open the mouth. 

 Because of this condition the disease is commonly 

 known as lockjaw. 



The spread of the disease does not occur through 

 healthy animals coming in contact with animals 

 having tetanus, but by inoculation. The germ of 

 tetanus is present in the soil, manure and dust. 

 It enters the body by way of wounds, especially 

 punctured and bruised wounds. The injury may 

 result from stepping on a nail, and the germs are 

 planted in the deeper structures of the foot. Such 

 a wound usually has poor drainage, the horn of the 

 hoof closing the mouth or opening. Here the germs 

 grow and produce a poisonous toxin that is said 

 to be the most powerful produced by any bacteria. 

 This toxin acts on the nerve centers of the brain 

 and spinal cord, causing extensive spasmodic con- 

 traction of the body muscles. 



Tetanus sometimes occurs in the absence of any 

 noticeable wound. It may be in such cases that 

 the seat of the infection is a slight abrasion of the 

 skin, or the lining membranes of the respiratory 

 and digestive tracts. The tetanus bacillus is a 



