SPECIFIC DISEASES 



infected by tuberculous fowls they are predisposed to in- 

 fection, as the evacuations of diseased birds contain the 

 organisms of tuberculosis. 



Pheasants that are reared under natural conditions are 

 unquestionably much less likely to develop the disease than 

 birds reared under artificial conditions. When Pheasants 

 have been interbred they become physically defective, and 

 this favours the development of tuberculosis or consumption. 

 It is customary to regard this malady as hereditary ; therefore 

 infected stock birds should be destroyed. 



Tuberculosis is due to the presence of minute living 

 organisms, known as bacilli, circulating in the blood and 

 lymph streams, with a disposition to locate themselves in the 

 tissue or organs, such as lymphatic glands and the liver, 

 where their presence sets up minute new growths known as 

 tubercles, which in advanced cases may stud the whole 

 surface of the liver, penetrate into its substance, likewise 

 lead to the production of variable sized new growths in 

 connection with the mesentery glands, which are at times 

 of stone-like consistency. 



The chief signs of tuberculosis are gradual emaciation. 



The introduction of infected broody hens may be a source 

 of infection, therefore every game-rearer should make it his 

 duty to select fowls kept on grass runs, and where the birds 

 are likely to be free from the trouble under consideration. 

 Tuberculosis is certainly much less frequently encountered 

 in Pheasants than in domestic fowls, the reason for this 

 being — in the writer's opinion — attributable to the different 

 conditions of existence and other reasons of secondary 

 importance. 



253 



