222 



details of the procedure are matters of 

 secondary consideration ; the one essential 

 thing is to make sure that the animals 

 have been adequately inoculated. Our one 

 guide is to produce a reaction, such as will 

 protect against reinoculation ; and pro- 

 vided this be done, little significance 

 would seem to attach to its particular 

 features or mode of production. 



In arranging for the inoculation of 

 herds it is desirable to have a suitable 

 bleeder on the spot, and to use the blood 

 as soon as possible after it has been shed 

 and defibrinated ; but if for any reason 

 this cannot be done, the inoculations may 

 be performed with blood transmitted from 

 a distant place or station. The possibility 

 of thus transporting blood was first 

 pointed out some years ago by Mr. Barnes, 

 M.E.C.V.S., of Eockhampton. As an in- 

 dication of what may be done in this way, 

 I venture to insert here some observations 

 made during the course of our experi- 

 ments. 



Our initial inoculations were performed 

 with blood sent from Brisbane to Sydney, 

 the interval elapsing between the bleding 

 and the inoculation being three days. 

 The animals inoculated exhibited refrac- 

 tory reactions, were immune to reinocula- 

 tion. and, although getting tick fever, did 

 not succumb when exposed to ticks at 

 Greenfell, and were not worse tlian many 

 animals inoculated with recently shed 

 blood. The same sequence of events oc- 

 curred in relation to a second sample of 

 blood obtained in the same way. A sam- 

 ple of blood sent from Grafton to Sydney, 

 used after an interval of four days, pro- 

 duced a good reaction in the animal in- 

 oculated with it. 



With the idea of obtaining some guide 

 as to the length of time blood would re- 

 tain its infectivity after being shefl, the 

 following experiment was ])erformod : — 

 Blood was taken by Mr. Stewart from 

 three animals at Eockhampton — one in- 

 oculated, and two controls. Some sent to 

 Mr. Archer, antl user! three days after col- 

 lection, produced goorl reactions in all 

 animals inor-iilatod. Some sent to Mr. 

 Pound at Brisbane, anfl used two days 

 after collection, produced good reactions 

 in all animals inoculated. Some sent to 

 me in Sydney, and was used five days after 



collection, but of the three animals in- 

 oculated only two exhibited a very slight 

 reaction. Thanks to the courteous as- 

 sistance of Mr. Archer and Mr. Pound, we 

 were thus in possession of facts which in- 

 dicate that the infectivity remains in shed 

 blood for between three and five days. 



It must be stated, however, that in the 

 various observations just mentioned, the 

 collection and transmission were con- 

 ducted by specially skilled individuals in 

 such a way as to materially lessen the 

 chances of putrefaction. In less expert 

 hands, and with faulty methods, the blood 

 might become putrid within the times 

 above mentioned. It need scarcely be said 

 that the slightest taint makes the blood 

 utterly unsuitable and dangerous. As a 

 practical rule, it may be taken that trans- 

 mitted blood should not be relied upon 

 when it has been more than two days on 

 its journey. 



Conclusion. 

 The conclusions arrived at in my pre- 

 vious report, based to some extent on the 

 observations of others, can now be re- 

 viewed in the light of our own subsequent 

 experience, recorded in this report. 



The need for maintenance of the first 

 line of defence there indicated— viz., the 

 exclusion of tick-infested cattle, with com- 

 pulsory crush inspection and dipping ot 

 possibly infested beasts— is aftorded the 

 strongest support by the facts concerning 

 cattle ticks presented in Part V. of this 

 report It is obviously our best pohcy to 

 spare no eft'orts in keeping the ticks out 

 of the Colony as long as possible. ihe 

 recent success of the Government m secur- 

 in^^ the continuance of an adequate butter 

 area is a matter upon which the respon- 

 sible authorities are to be warmly con- 

 gratulated. . 



The conclusion previously arrived at as 

 to the value of inoculation is also borne 

 out by the more recent observation re- 

 corded in Part VI. of this report. It is 

 plainly evident that, although the pro- 

 tection conferred bv inoculation may not 

 be perfect, it is yet such as to be of very 

 o-reat service in reducing the ravages ot 

 tick-fever. The difference between in- 

 oculated and control animals observed at 

 Greenfell were really more obvious to the 



