57 



it applicable to the intra-dermal test. This latter method of test- 

 ing continues to give absolute satisfacion especially since a method 

 has been evolved by this Division for the speedy retest of any 

 questionable reactions. This consists in the injection — intra-der- 

 mally — in a fold of skin on the side of the neck of an equal dose 

 of concentrated tuberculin, as that ordinarily injected into the 

 sub-caudal fold. Owing to the thickness of the hide on the side 

 of the neck there is little or no danger of the point of the needle 

 penetrating the cutis, making the injection sub-cutaneous instead 

 of intra-dermal. The neck region, however, is less accessible or 

 convenient for injection under ordinary circumstances and the 

 resulting reaction is less conspicuoiis, requiring palpitation or even 

 accurate measuring in its interpretation. But where there is the 

 slightest doubt about the result of a sub-caudal injection the neck 

 injection should be resorted to immediately and an examination 

 48 to 72 hours later will dispel any doubt as to the diagnosis. 

 This was beautifully demonstrated on a high priced Holstein 

 bull recently imported which failed to give a characteristic reac- 

 tion to the sub-caudal injection even though the local swelling 

 indicated the possible presence of infection. The animal was 

 then injected on the side of the neck an^l 50 hours later the double 

 fold of the hide at the place of iniection had assumed a thickness 

 four times greater than original. This swelling w^as hardlv notice- 

 able so long as the hide was allowed to remain flat on the neck 

 and only became conspicuously manifest when the hide was raised 

 in a fold between the index finger and the thumb. With this 

 neck test to assist in doubtfid cases T feel absolutely confident 

 that the intra-dermal form of the tuberculin test may be con- 

 sidered absolutely reliable as a means of diagnosing bovine tuber- 

 culosis. 



Like in the former general tests the cooperation of the local 

 Board of Supervisors, through the City and County Physician, 

 has been extended through the assignment of ]\Iilk Inspector 

 Richards to assist in making the tests. His personal acquaintance 

 with all the milk producers and his intimate knowledge of the 

 composition of the various herds has been of good value to us in 

 carrying on this work. 



Glaiidcrs. 



I regret to report the appearance of glanders in a stable where 

 the disease has been known to occur on previous occasions, but 

 where no case has developed for more than two years. As this 

 recrudescence of the disease after such a long interval is indica- 

 tive of the presence on the premises of an old "carrier" of the 

 infection — that is, an infected animal exhibiting no symptoms of 

 the disease — it has been decided to test all the animals in the 

 stable as well as such animals which have been in contact with 

 these. This occasion will lend an opportunity to apply a new 



