ANIMAL INOCULATION 123 



thigh or abdomen ; mice in the dorsal region or at the 

 root of the tail (dorsally), the hair being clipped, and 

 the skin disinfected, but this is not generally necessary. 

 Numerous mechanical holders have been devised for 

 animals, but are not as a rule required. Rabbits may 

 be inoculated intra-venously by one of the large veins 

 in the ear. The ear is -shaved, and the skin is well washed 

 with a little alcohol with vigorous rubbing ; the base of 

 the ear is lightly pinched so as to obstruct the venous 

 but not the arterial circulation, and render the vein 

 prominent, and the injection is made with a small syringe 

 fitted with a fine needle, the needle being passed into the 

 vein towards the base of the ear. After the withdrawal 

 of the needle the wound is compressed for a little and may 

 be dressed with some antiseptic wool and collodion. 



Guinea-pigs frequently eat the carcases of their dead 

 companions, so that the cages should be examined twice 

 daily, and, if the carcase is required, it may be advisable 

 to keep each animal in a separate cage. 



The phenomena occurring after inoculation must be 

 noted. Usually these are not very obvious in the rodents, 

 but loss of appetite, sluggishness, staring coat, convul- 

 sions, etc., may be observed. The weight of the animal 

 is a good index of what is happening. If the infection is 

 serious, the weight rapidly falls ; if the animal is to 

 recover, its weight soon begins to increase after the pre- 

 liminary fall. The temperature in the rectum may also 

 be taken, but is not so valuable, as in the guinea-pig 

 variations occur from mere handling or other slight causes. 

 The temperature of the guinea-pig averages 38-6, but 

 varies between 36 and 39 C. (Eyre). 



The examination of the dead animal should be carried 

 out with as little delay as possible. For dissection, the 

 body should be pinned out on the back on a board, which 

 may stand in a shallow enamelled iron pan, by pins or 



