268 BACTERIOLOGY. 



The hair is removed from the neck by means of a pair of bent 

 scissors. The part should then be shaven clean and washed with an 

 antiseptic. A median incision is made along- the neck with a sterile 

 scalpel, and the skin is loosened from the subcutis by using- the handle 

 of the knife, or the fing-ers. The external jugular vein which lies on 

 the side, covered by subcutaneous tissue, is now exposed as carefully 

 as possible. The size of the vein is such that no difficulty will be ex- 

 perienced in finding- or entering- it. A ligature should then be ap- 

 plied to the vein and the wound in the skin, sewed up as neatly as 

 possible. A few tufts of cotton should be spread over the incision, 

 and then moistened with collodium. When this has dried the animal 

 can be released. 



FIG, 45. Latapie's animal holder. 



In the above method of inoculation, every possible pre- 

 caution must be taken to prevent accidental infection. 

 The hands, as well as the neck of the animal, must be 

 thoroughly disinfected. All instruments, ligatures, etc., 

 must be sterile. The instrument sterilizing' case, shown in 

 Fig. 48, p. 275, is used for this purpose. 



Intravenous injection is practised frequently during 

 the immunization of horses against diphtheria, pest, etc. 

 The operation as made on the horse is relatively as easy as 

 the injection into the veins of the ear of a rabbit. An at- 

 tendant should compress the jugular vein with the thumb, 

 while the operator cuts away the hair over the vein. This 

 cut area is then thoroughly rubbed with lysol, or some 

 other disinfectant. The skin is first pierced with a lance, 

 and then the trochar is inserted as nearly parallel to the 

 vein as possible. After withdrawal of the trochar, the 

 opening should be compressed by a finger, and eventually 

 it may be coated with collodium. 



