1 Juty, 1899,] QUEENSLAND AGRICULTURAL JOURNAL. 79 
experiments so far, then, seems to force the conclusion that when, as a result 
of the injection of tuberculin, a definite re-action is obtained, the animal is 
affected with tuberculosis. It is true that some observers have been unable to 
find traces of the disease on post-mortem examination after the re-action has 
been apparently definite; but how far such inability to find the lesions 
has been due to careless, insufficient, or hurried search on post-mortem it is 
difficult to say. In other cases, notably in one or two States in America, where the 
test has been carried out under adverse and unsuitable conditions (in saleyards, 
market-stalls, &c.); and where sufficient care has not been used in interpreting 
the temperature-records and other factors component to a “re-action,” 
numerous mistakes have been made. When, on the introduction of the test, 
operators were not as familiar with its intricacies and delicacies as: they now 
are, mistakes occurred occasionally ; and in one case as many as 11 per cent. of 
animals which were supposed to have re-acted were found to be free from the 
disease on post-mortem examination. But the accumulated experience of the 
past five years in all countries in the world in which the test has been put into 
operation seems to prove conclusively that, while errors and mistakes have been 
made, not more than an infinitesimal number are chargeable to the failure of 
tuberculin itself. Professor McFadyean, M.B., F.R.C.V.S., &c., Dean of the 
London Veterinary College, who at first was openly sceptical as to the universal 
reliability of tuberculin, has recently announced that when the test is carried out 
in an intelligent and discreet manner it is “ practically infallible.” And the 
results of the small series of experiments carried out in Victoria would seem to 
endorse that dictum. 
The question arises, howeyer, and has been asked, whether, in case there is 
no re-action after tuberculin injection, it is certain that no tuberculosis exists. 
That is to say, whether in some cases tuberculin fails to indicate the disease 
whenitis present. Perhaps this does occur occasionally—so rarely, however, and 
in such circumstances that for practical purposes the reliability of tuberculin in 
a negative as well as an affirmative sense may be definitely affirmed. 
In this connection it will be of interest to note the following particulars:— 
On the occasion of the second testing of Herd Z., in May last, the chairman ° 
authorised me to purchase one of the healthy cows, that had not re-acted on 
either occasion, for post-mortem examination; and the owner, on being made 
acquainted with the object of the purchase, at once generously offered to give 
up another of the non-re-acting cows for a like purpose. The selection of the 
cows was left to the farm manager, who chose two which, prior to application of 
the test, he had been strongly suspicious were tuberculous. The temperature 
charts of each of these cows on each occasion, together with a brief history and 
details of the post-mortem examination of each, are given in Table I.* 
TABLE I. 
GivING THE TEMPERATURES BEFORE AND AYTER INJECTION or Two Non-ReACTING ANIMALS. 
» Temperature before Temperature after 
Injection, | Injection. 
: | Varia- 
= EE oo ; j tion. 
Four Half-_ Mean, | Twelve | Vifteen | Eighteen 
hours. | hour. | hours. | hours. | hours. 
| 
es 102'5 1020 | 102'3 102°0 | 102°5 | 1023 | 102:3 | Nil. 
| 
4 
| 
| 
U 
| 1 
iGjeaea |e aa | ee, 
| 
No.2} 13:0 | 1023 | 1026 1015 1015 | 1020 | 1017 | 11 fan 
| ; | 
First Test—January, 1897 
' { | | 
No.1 | 1022 1030 | 1026 100°6 | 101:0 at 100°8 | 18 fall 
Second Test—May, 1898 ! | 
| 
\ | | 
No.2] 1013 | 101°6 1014 101'9 . 1015 we 101'7 | 0°3 rise- 
| 
* Two more of the non-re-acting cows of this herd have been slaughtered and carefully 
examined since the text of this report was written, and not the slightest trace of tuberculosis 
could be found.—S.8.C 
