VETERINARY MEDICINE. 883 



The intradermal test for tuberculosis in cattle and hogs, C. M. Haring and 

 R. M. Bell {California Sta. Bui. 2.'f.i (lOlJf), pp. 9.i-15J,, figs. 20).— Some of the 

 material reported in this l)ulletin has been noted from another source (E. S. R., 

 29, p. 490). "In all, 4,92G intradermal tests have been made on 4,001 cattle, 

 1,614 of which reacted, and there has been an opportunity to check these 

 results by autopsies in 341 cases and by the discovery of lesions on physical 

 examination in 54 additional cases. To 291 cattle that reacted to the intra- 

 dermal test the subcutaneous test was subsequently or simultaneously applied, 

 and 282 cattle reacted. Forty-four cattle with a positive intradermal reaction 

 gave no thermal reaction to the subcutaneous test." 



It was possible to brinj: to autopsy only 10 of the cattle which failed to react 

 to the subcutaneous method, but in 9 of these tuberculous lesions were noted. 

 Thirty-five of the cattle which failed to react to the intradermal test later 

 reacted to the subcutaneous test. " Two of these cows which rejicted to the 

 subcutaneous method, but showed no swelling at the point of intradermal 

 injection, were found on autopsy to be tuberculous." 



The cattle which reacted to the intradermal test and manifested a local 

 swelling usually showed a thermal reaction which resembled that produced by 

 the ordinary subcutaneous injection. When an intradermal injection was given 

 a few days after a subcutaneous injection, the results obtained were not reliable. 

 *' The thermal reaction which accompanies the intradermal iujection usually 

 subsides in 20 hours, but it seems desirable not to apply the subcutaneous test 

 for several days after the intradermal. The longer the interval the better." 



While the results with Koch's tuberculin in 10 per cent solutions and with 

 alcoholic precipitated tuberculin in 0.5 per cent solutions compared favorably 

 in accuracy with the usual subcutaneous method, a more satisfactory method 

 seemed to be to give one-fifth cc. of a 5 to 50 per cent solution of an alcoholic 

 precipitated tuberculin in the subcaudal fold and to administer 2 cc. of Koch's 

 old tuberculin (10 per cent) subcutaneously. "With this kind and strength of 

 tuberculin the local reactions are pronounced and the thermal reactions are 

 as characteristic as those that occur from subcutaneous injections alone." 



The application of strong disinfectants at the site of injection is to be avoided. 



The intradermal reaction is much harder to interpret than either the 

 ophthalmic or the subcutaneous test inasmuch as a great deal of experience is 

 necessary to interpret the significance of the local swelling. This is especially 

 true when glycerin is present in the tuberculin. "When 5 per cent solutions 

 of potent precipitated tuberculin are used both the ophthalmic and intradermal 

 methods equal the subcutaneous test in accuracy, but we have found that the 

 ophthalmic method is unsuitable for use in routine testing under California 

 conditions, except when the cattle can be kept indoors. The intradermal 

 method has proved very satisfactory in the out-of-door tuberculin testing 

 frequently necessary in this State, and for the nonofficial testing of large num- 

 bers of cattle is preferable to the subcutaneous method. ... By adminis- 

 tering the ophthalmic, intradermal, and subcutaneous tests simultaneously, a 

 higher percentage of tuberculous cattle will be detected than if dependence is 

 placed on one test alone. 



The intradermal test was also found very valuable for detecting tuberculosis 

 in hogs. A dose of one-fifth cc. of 10 per cent precipitated tuberculin was used 

 and with it tuberculous hogs often showed a thermal as well as a local reac- 

 tion. No decision was reached as to the best site for making the injection. 

 The larger swellings, however, were noted when the injection was made at the 

 edge of the ear. For measuring the swelling a special form of caliper is de- 

 scribed and illustrated. 



