TUBERCULOSIS AND PNEUMONIA. 137 



pheasants is tuberculosis*. This disease is very infectious, 

 the infection being conveyed by the excreta contaminating 

 the soil, and so getting on to the food. The birds affected 

 become anaemic, dull, and emaciated, and their loss of weight 

 is so well known to pheasant breeders that they are termed 

 " light birds." The real diagnosis of avine tuberculosis can, 

 however, only be made by post-mortem examination, and in 

 many cases a bacteriological one is also necessary. The 

 disease is produced by a specific bacillus, closely allied to, if 

 not the same as, the bacillus which produces human tuber- 

 culosis. This obtaining entrance with the food first causes 

 tuberculous ulceration of some portion of the intestinal tract; 

 the spleen and liver are next affected, and the bird becomes 

 thin and dies. The lungs are seldom the seat of tuberculous 

 disease, though it has beeu seen there, and also in very rare 

 cases in some of the lymphatic glands. The appearance of 

 the liver is very marked, being mottled with white nodules 

 from the size of a pin's head to that of a pea; but it is not 

 safe to rely wholly upon the appearance of this organ, for a 

 somewhat similar condition is produced by coccidiosis, and in 

 many cases a bacteriological examination alone can determine 

 the difference. Unfortunately there is no curative treatment 

 for this disease, and, when once it makes its appearance, the 

 only thing to do is to kill and burn all sickly birds, and put 

 the healthy ones on to i'resh ground. It is even better to 

 kill off all the old stock and get a fresh and healthy supply of 

 birds, at the same time taking care to burn all the old 

 aviaries and to build new ones on fresh ground. 



Young pheasants are very liable to pneumonia. This 

 disease, during the cold and wet seasons of 1909 and 1910, 

 caused the death of many young birds, especially the weaker 

 and later hatched. 



The most troublesome and fatal disease known as the 

 "gapes" is caused by the presence of small red worms in the 

 trachea, or windpipe. For the first careful demonstration of 

 the cause of this disease we are indebted to the late Dr. 



