July 4th they were tested with 4 cc. of Bureau of Animal Industry 

 tuberculin. Four of them showed a rise in temperature, but the 

 curve was not typical of a tuberculin reaction. We have proven 

 that all but one of them were tubercular, in the following manner : 



Seven were autopsied, and in six of these extensive lesions were 

 found in the lungs and associated lympathic glands ; in the other the 

 retropharyngeal glands only were involved. One was proven 

 tubercular by infecting a guinea pig from pus from a tubercular 

 abscess in the prepectoral region. This cow was eventually autopsied 

 after having been inoculated in the carotid artery, as is describee 

 later in this paper. The eighth cow was proven tubercular by in- 

 fecting a guinea pig with her feces. One of the interesting things 

 to be noted is that the tuberculin test failed to give a reaction, 

 although the animals were actively tubercular. We have observed 

 this failure to react in an instance where about twenty reacting 

 dairy cows were removed from a dairy ^ dried up and turned into a 

 mountain pasture. When re-tested several months later most of 

 them failed to react. These observations support us in the stand 

 that in removing cows from dairy herds because they react to the 

 tuberculin, no re-tests should be permitted. We believe the rule 

 should be : Once reacted, always condemned. Outdoor life and 

 freedom from the drain of milking may possibly cure some, cows, 

 but the cases just described show that, although they may improve 

 in condition and cease to react to tuberculin, they may still be dis- 

 seminating virulent bacilli, and that young, susceptible animals 

 quickly contract the disease, even under an environment which acts 

 with benefit on old and chronically tubercular dairy cows. 



Re-testing Recently Tuberculinized Cattle. 



Tests of Vallee's method by re-testing recently tuberculinized cat- 

 tle have been made on thirty-seven reacting cows. By this method it 

 is claimed that animals can be successfully re-tested in forty-eight 

 hours after a previous injection. The procedure is to inject a double 

 or triple dose and take the temperatures every two hours from the 

 second to the eighteenth. The reaction is said to usually occur much 

 sooner than in the original test. The results of our work as given in 

 the following table are based on the injection of 4 cc. of tuberculin at 

 the retest, the temperature being taken every two hours from the 

 second to the eighteenth hour after injection. 



It is interesting to note in corroboration of Vallee's observations 

 that, in the retests made within five days, the animals reacting to the 

 second injection usually had a rise of temperature sooner than at the 

 first test, but the only conclusion to be drawn from this limited num- 



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