New YorK AGRICULTURAL EXPERIMENT STATION. a7 
tion there would be no reaction although the disease may soon 
develop. To overcome this danger a subsequent test should be 
made in from three to six months. (3) It is known that cows that 
have reacted, may, because of the arrest of the disease, fail to re- 
act subsequently but later the disease may start up again, when 
the animal would react. We have records of several cases of this 
kind. Great care must be exercised, therefore, in the interpreta- 
tion of negative results, especially in tests made in herds where 
tuberculosis exists, and where it is possible that the animals failing 
to react have been infected. 
COMPOSITION OF THE STATION HERD. 
In December, 1900, the Station herd contained seventeen mature 
cows and eleven heifers ranging in age from eight months to two 
years. Eight of the cows were full-blooded Jerseys and the re- 
mainder, with a single exception, were Jersey grades. Two of the 
cows had been raised on the farm, while the remaining fifteen had 
been purchased in 1898-1899. The purchased animals represented 
nine herds in the central part of the State. 
Care had been exercised in purchasing to procure desirable ani- 
mals from all points of view. They were not bought, however, 
subject to the tuberculin test.4 
The young stock had all been raised on the farm and repre- 
sented the most promising heifers of the two preceding seasons. 
PoeNviNGe PUBERCUEROSIS IN- THE HERD: 
In the fall of 1900, Cow No. 8, which had been purchased by 
the Station in 1898, steadily lost flesh. She was given a physical 
examination on Noy. 27 by a local veterinarian who pronounced 
her tuberculous. She was promptly killed and found to be suffer- 
ing from the disease in its advanced stage.” As in many other 
* Soon after the arrival of the new animals abortion became troublesome 
and continued for some years. This trouble- seriously interfered with our 
later attempts at renewing the cows through their offspring as not only did 
many of the old cows lose a calf but for some years practically every heifer 
lost one calf and in one case two in succession. 
* The autopsy notes show the following distribution of lesions: 
“Right sub-maxillary lymph gland contained pus. Caudal mediastinal 
lymph gland enlarged to eight inches in length and tuberculous. Lungs 
