60 QUEENSLAND AGRICULTURAL JOURNAL. [1 Jaw., 1899- 
fact must not be overlooked that a small bubble of air injected into the blood ~ 
vessel may cause instant death of the animal. Directly the syringe is coupled 
with the needle the cord is removed from the neck, and the blood ejected fromm 
the syringe into the vein. It is advisable on withdrawing the needle to pinch 
the skin around the wound and apply a little more carbolic solution before 
releasing the animal. After each calf has been inoculated, they should be kept 
in a well-grassed paddock with plenty of fresh water, and their temperatures 
taken regularly night and morning from the eighth to the twenty-fourth day 
after inoculation. Those giving a very decided reaction—viz., temperature 
rising from the normal (101°5 degrees Iahrenheit) to 106 degrees Fahrenheit 
or higher—are, when they have completely recovered (which will be within six 
weeks), suitable subjects for drawing blood from for general inoculation 
purposes, and are generally spoken of as ‘immune calves.” ‘The reasons wh y 
young animals are preferred are:—(1) They are easily handied and managed_ 
(2) The subcutaneous tissue of the neck between the jugular vein and the 
skin is not very thick. (3) In inoculating blood froma calf there is very 
little risk of introducing tuberculosis, which is seldom found in calves ; 
however, in order to minimise any possible risk from this disease, the calves 
can be all previously tested with tuberculin. 
METHOD OF DRAWING THE BLOOD FROM THE IMMUNE CALF AND 
PREPARING SAME FOR GENERAL INOCULATION PURPOSES. 
The immune calf is thrown on its left side, and a cord tighteneq 
round the neck as previously described, but instead of a needle the 
operator takes the trocar (with canula attached) in his right hand, anq@ 
with itin a vertical position steadily pierces the skin into the vein. Im ~ 
mediately the point is through the wall of the bloodvessel, the instrument — 
is held in a slanting position and gently pressed further into the distendeq 
vein. ‘The operator then withdraws the trocar with the right hand, the while 
holding the sheath or canula with his left, and keeping it well into the blood 
vessel. If the vein has been successfully pierced, blood will flow copiously_ 
Tf it does not flow, the operator returns the trocar into the sheath and gentl 
withdraws both of them a very slight distance but not out of the wound, 
because at the first insertion the trocar may have been forced through the veix 
or on one side of it, which often happens in the case of young thick-neckeq 
bulls. However, as soon as the blood flows freely on withdrawal of the trocaz. 
it is caught in a perfectly clean wide-mouth bottle. From an anima] 
six months old halt-a-pint of blood may be taken, and as much as 
pint and a-half from a yearling. In the summer time, when the fliex 
are plentiful, a little tar should be placed on the wound before the 
calf is released. As soon as the requisite amount of blood is drawn, it 
should be well stirred for about five minutes with a whisk formed of half-a_ 
dozen wing feathers from a duck or fowl]. At the end of that time the whisk | 
when lifted out, will be found to be covered with stringy-like fibrinous blood — 
stained matter. This is the fibrin, and its removal prevents the blood thickening | 
clotting, or coagulating. The process of whisking and removing the fibrin ig 
known as defibrination. Defibrinated blood is that which has been so treated | 
The blood is afterwards strained through a piece of clean linen or calico into 
another clean bottle, and is ready for use. 
DETAILS OF THE PROCESS OF INOCULATION. 
Allowing 5¢.¢., which is equal to one teaspoonful, for one bullock, one pint 
of defibrinated blood would be adequate to inoculate about 100 cattle. To 
minimise, as far as possible, the risk of contamination, the following 
precaution may be adopted:—The operator puts about 2 ounces of blood fron, 
the stock bottle into a small wide-mouth bottle, which is covered with clean 
linen or calico. The smail bottle is for actual work of inoculation, and shoula 
be filled up as required, 
