164 LIVESTOCK ON THE FARM 



The test docs not give any indication as to the stage of the 

 disease. A cow in which the disease is just starting may 

 react like one in which the disease is well advanced. 



During the first stage of the disease no one can make 

 a diagnosis by physical means. After the disease has become 

 well advanced a cow may show a lack of thrift or may even 

 lose flesh. She may or may not cough. These symptoms may 

 also result from other causes. 



Upon postmortem examination a tuberculous animal will 

 show tubercles in the lungs, along the intestines, in the glands 

 along the intestinal wall, on the inside of the chest cavity, in 

 the glands of the neck or in some of the other body glands. 

 These tubercles are enlargements, inflamed around the out- 

 side, with pus in the center. Sometimes this is soft and 

 sometimes it is hard but always it has a gritty nature when 

 cut through with a knife. This grittiness is due to limy sub- 

 stances left by the germs. The pus is caused by germs dying 

 on the inside of a tubercle for the want of food. 



Milk from tuberculous cows should not be fed to calves or 

 to pigs, except after pasteurization or sterilization. Pigs 

 are very easily infected and the disease works very rapidly 

 with them. The author knows of 40 fall pigs that died of 

 this disease by January. Cattle may live several years and 

 in fact may sometimes have the disease and die of old age. 

 Animals that are strong constitutionally and are well fed 

 will not contract the disease as readily or succumb as quickly 

 as those that are not so strong. 



ABORTION 



Another disease which causes great losses among dairy 

 cows is contagious abortion. This is also a germ disease. 

 The germ in this case lives and works in the vagina and causes 

 the foetus to be expelled. 



This disease may be carried by the bull or by cows coming 

 into contact with each other so that the germs get from one 

 to another. Litter or manure may also carry the germs and 

 spread the disease. Before buying animals or using a herd 

 bull from another herd one should make sure that the herd 

 is free from this disease. 



