The Intrapalpebral and Intradermic Palpebral Tuberculin Tests

The Intrapalpebral and Intradermic Palpebral Tuberculin Tests

ABSTRACTS. from the .bronchial glands of each was proved to contain living virulent bacilli by the inoculation of guinea-pigs. These experiments show...

142KB Sizes 0 Downloads 13 Views

ABSTRACTS.

from the .bronchial glands of each was proved to contain living virulent bacilli by the inoculation of guinea-pigs. These experiments show that the tolerance of bovine a:J.imals to infection with tuberculosis is dependent upon the presence in their systems of living tubercle bacilli. The following conclusions are drawn :1. The lipoids soluble in boiling acetone and benzene extracted from tubercle bacilli exercise no protective action. 2. Crude or precipitated tuberculins, such as are usually prepared ID laboratories, exercise an obvious effect, which is merely a slowing of the process of development of the disease. 3. Bacilli killed by heat derived from ordinary glycerinised culmre media possess a slight protective power, due to the small amount of tuberculin ·carried aloug with them or contained in their bodies. 4. The intact bacillary protoplasm obtained from dead bacilli which are devoid of tuberculin possesses no immunising action at all. s. Lasting tolerance possessed by bovines to infection with tuberculosis -is due to the presence in their systems of living bacilli. The saprophytic existence of tubercle bacilli in the system leads to the production of soluble immunising substances different from those obtained in artificial culture media. (Calmette and Guerin, Ann. Ins!. Past., Vol. XXVIII., NO.4, April 19 14, pp. 319-337.)

THE INTRAPALPEBRAL AND INTRADERMIC PALPEBRAL TUBERCULIN TESTS. THE author discusses at some length the objections that may be raised to the ·use of the subcutaneous tuberculin test, dividing these objections into those which concern the practitioner and those which concern the owner. The principal objections encountered by the practitioner are: The amount ·of trouble involved in taking the temperatures; the possibility of errors being made in reading the temperatures; the difficulty of interpreting irregular results; the necessity of keeping the animals indoors, which is in itself sometimes sufficient to cause.a rise of temperature; the impossibility of applying the test to animals in a febrile condition; the necessity of carrying out the test at certain hours at the risk of makIng serious errors. These objections are not objections to the method Itself, but are due to the conditions under which the test has to be carried out. As regards the objections that may be raised by the owners of cattle, the author poinls out that there may be a reduction In the secretion of milk in reacting animals. There is a danger of specific mastitis occurring after .a longer or shorter interval, and, finally, there is the danger of aggravating the general condition of diseased animals In view of these objections the author is convinced that the local tests, intradermic and intrapalpebral, are more useful, more practical, and more economical from the owner's point of view, and from the practitioner's point of view more remunerative than the old method of subcutaneous injection. The difficulty of applying the test is imaginary, provided a suitable syringe is used; this should have a capacity of I ccm. The needle should be .about If cm. in length and '7 mm. in diameter. The barrel of the syrmge should be graduated into tenths, and the piston. rod should have a travelling ,stop on it.

266

ABSTRACTS.

It is advised that . I cc. of ordinary tuberculin should be used, special tuberculin of any kind not being required. When the test has been properly carried out a little swelling should be formed in the sub-epidermic tissue about the size of a large lentil, where the tuberculin is injected. Reactions are said to make their appearance more rapidly and more dearly the more recent and the more limited the lesions. After thirty-six to forty-eight hours the eyelid becomes swollen, redematous. and slightly tense, and the eye appears sunken. The tissues lose their suppleness, the skin is rigid and sometimes reddish and moderately sensitive. There may be slight lachrymation. EYen a moderate reaction is rendered quite obvious by comparison with the opposite eye. When the palpebral and caudal tests are carried out simultaneously they agree exactly, and should one of the tests have been improperly carried out. the other gives a positive result. An important practical point is that the tests are complementary, or they correct each other. For those who find the intradermic palpebral test too delicate a manipulation, a subcutaneous injection of t to ~ cc., or more, of tuberculin may be made into the upper or lower eyelid, this yielding a local reaction as characteristic as the intradermal test. The author has carried out tests upon about sixty animals, using different. doses of tuberculin, and he has found that as good results can be obtained. with k cc. as with k cc. If, however, the larger dose be used, the test approximates to the sub· cutaneous method, in that it is likely to produce a temperature reaction. with the accompanying disadvantages. . The method of testing is held to be free from all the objections that have: been raised above against the subcutaneous method. In practice the author makes an injection into both eyelids. (Moussu~ Bee. MU Vet., Vol. XCI., No. 13, 15th July 19 1 4, pp. 425-434.)

THE INTRADERMIC TUBERCULIN TEST APPLIED' TO THE EYELID. THE idea of applying the intradermic tuberculin ~est to the eyelid instead of the anal fold was suggested to the author by Lanfranchi's experiments in connection with the diagnosis of glanders by means of mallein used in this way. He does not, however, follow Lanfranchi's method exactly. Whereas in the experiments carried out by the latter the ordinary dose of mall