i6 Bulletin 150. 



Lymph glands ui front of the middle of the shoulder blade m ay- 

 be suspected if of unequal size and form on the two sides, if hard 

 and nodular, or if soft and fluctuating. They rarely caseate and 



burst. 



Other lymph gla7ids that may be similarly affected, and that 

 are superficial enough to be felt, are the glands at the entrance of 

 the chest in front of the two first ribs, the glajids 07i the flank 

 above and in front of the stifle, and, in the young, the glands 

 situated high up in the groiii. 



Tuberculosis of the bones a7id joints is seen in 3'oung growing 

 animals, affecting especially the large joints of the limbs, the 

 elbow and knee, the stifle and hock, but also at times the bones 

 and joints of the digits. The ends of the bones become enlarged 

 and tender and the joints overdistended, tense and elastic. The 

 lameness ma3^ be extreme. 



PROPORTION OF OCCULT CASES. 



In herds which have the disease in the most intense form, by 

 reason of long standing, indoor life, and repeated reinfection 

 nearly all may be detected by the objective S3^mtoms, but in such 

 herds nearly every animal is diseased. In ordinary- herds, where 

 the disease is less intense, at least two- thirds of the diseased ani- 

 mals would escape under such an examination. In one herd of 

 70 head in which the tuberculin test condemned 24 head (being 

 50 per cent of the mature animals) I left the examination after 

 slaughter to the veterinarian of the A. J. C. C. who was at the 

 time skeptical as to the value of the tuberculin test. He wrote 

 me afterward of his surprise at finding ever}'- one of the 24 

 condemned animals tuberculous, when not one of them had 

 shown symptoms by which he could recognize the disease in 

 life. This is no exceptional case, and may be advanced rather 

 as a typical example of the ordinar}^ infected country herd. 



It is manifest that if we aim at speedil}^ and certainl}^ clearing 

 a herd of tuberculosis we must have some better method of diag- 

 nosing the disease than the best physical examination. Attempts 

 have been made to discover the bacillus in the expectoration, 

 milk or nodular h'mph glands, but this requires prolonged care- 



