272 SWINE 



times the disease may last much longer. A hog may even 

 be affected with the disease and not show the effects of it 

 until after he is slaughtered. The duration of the disease 

 also is determined to a greater or less extent by the con- 

 dition of the animal and the amount of tubercular ma- 

 terial eaten. 



Kind of Pigs Affected. Young pigs are more subject 

 to the disease than older hogs, and brood sows are more 

 likely to be affected than barrows because during the 

 periods of gestation and lactation they are more reduced 

 in vitality, hence more subject to disease. A strong, 

 healthy, vigorous animal can withstand the attacks of 

 this disease as well as of others better than one that is 

 not in such a condition. Therefore it is not necessarily 

 true that all animals eating tuberculous feed become 

 affected with the disease. Those that are weakest in con- 

 stitution and have the lowest degree of vitality, or those 

 that eat the largest quantity of the diseased material, are 

 the ones that are affected first and also are the ones that 

 will succumb first. 



HANDLING A TUBERCULAR HERD. 



If the disease is present in a herd, it can very readily be 

 diagnosed before it has advanced sufficiently far to be 

 transmitted from one individual to another. The diag- 

 nosis consists in knowing whether the animals are thrifty 

 in appearance, whether they cough, whether they are 

 making rapid gains, or whether they are gradually losing 

 in flesh and finally die. If the glands of the neck are 

 affected to the extent that they become swollen, this may 

 also be used as a means of diagnosing. If the disease 

 seems to be present in a herd, the individuals that are ap- 

 parently the most affected should be immediately killed 



