ing pre-injcition tenipei'ature.s not exceed- 

 ing 103.1° and post-injection temperatures 

 exceeding 104" F. must be regarded as tuber- 

 culous while post-injection temperatures 

 above 103.1° and not exceeding 104." must be 

 considered as doubtful, and considered indi- 

 vidually. 



"It is the writer's belief, after tlie careful 

 examination of many tests and the making 

 of many post mortems following tuberculin 

 injection, tliat a slight rise may represent a 

 reaction. When the maximum temperature 

 ranges from 103.5° F. down to 103" F., or 

 even a few tenths of a degree less, the cases 

 are suspicious if the curve is well marked. 

 When animals with such temperatures are 

 slaughtered from 40 to 60% of them usually 

 i-eveal tuberculous lesions. AVItli our i»rc»ent 

 kno\vle«lKe «»iie osiiiuot be ho.siIIao of a re- 

 action with SI toiiuuTature oiir^ e having' Ji 

 iiiaxiiiiiini of less than 104" K., but in all 

 cases in wliifli tbe .siib.sequeut teiniieratiire 

 rang'es between KKt" and 104" should be con- 

 sidered Nuspiclous. There are a few cattle 

 owners who exclude from the herd animals 

 that give a temperature even lower than 103" 

 F. following the injection of tuberculin if 

 there is evidence of a gradual rise and de- 

 cline." (Moore.) 



Iiniiiiiuitv From Previous Injections of Tn- 

 berenlin. In some cases repeated injections 

 of tuberculin result in immunity to its action 

 so that it is onl.v possible to judge a tuber- 

 culin test correc'tly when it is positively 

 known that the injected animal or animals 

 liave not been treated with tuberculin at any 

 time within the preceding four weeks and 

 some authorities extend this limit to six 

 months and even a year. Nocard's experi- 

 ments showed that of 24 reacting cows only 

 33% reacted to a test applied 24 to 48 hours 



