68 



B. — Against Protosolc diseases. 



3. Piroplasmoses of equines :— Active immunisation witli the 



blood of immune animals. 



4. Piroplasmoses of cattle fredwater) :— Active immunisation 



with the blood of immune animals. 

 C. — Against diseases caused hy ultra- risible organisms. 



5. Blue-tongue in sheep : — Active immunisation by vaccination. 



6. Rinderpest : — 



(rt) Simultaneous injection of virus and serum of liyper- 



immunised oxen. 

 (b) Injection of bile (^vaccination). 



7. Horse-sickness :— Simultaneous injection of virus and serum 



of hyperimmunised animals (as yet only applied to mules). 



One injection of a small quantity either of 



(1) fully virulent matter in order to infect an animal and to obtain 



virus ; or 



(2) specific anti-bodies leads to the production of the required 



anti-bodies and only of a negligible amount of accompanying 

 anti-bodies. 



Only the specific rinderpest anti-bodies were observed, even at the 

 hyperimmunisation of oxen, with great quantities of virulent rinder- 

 pest blood in order to obtain a strong immune serum, recognised in 

 vivo by the successful treatment of animals ; in no instance were 

 clinical or anatomical phenomena due to haemolysis or precipitation 

 recorded. We are therefore confronted by the remarkable fact that 

 cattle do not produce isoly sines in their blood, i.e. substances with 

 the property of dissolving cattle blood in vivo or in vitro, even after 

 the injection of enormous quantities of blood. 



Goats are able to react with the production of isoly sines on in- 

 traperitoneal infusion of considerable quantities (800 and 900 c.c.) 

 of dissolved goat blood corpuscles. But these anti-bodies do not appear 

 in all goats treated in the same manner, nor does an isolytic goat- 

 serum dissolve the corpuscles of all goats.* 



As in goats, isoly sines arise in the blood of horse, mule, or donkey 

 after subcutaneous or intravenous introduction of blood, serum, or 

 peritoneal liquid of one of these three. The serum of animals treated 

 in this way is able to produce haemolysis in an emulsion of equine 

 blood in vitro, and also, as recorded by Theiler,t in the living 

 animal, t 



Theiler hypeiimmunised horses, mules, and donkeys already im- 

 mune (or salted) against the South African horse-sickness, that is to 

 say, he injected them in different manners with large quantities of 



* Ehrlich and Morgenroth, Berl. Ivlin. Wochenschrift No. 1, 1899. 

 t Annual Report o£ the Government Veterinary Bacteriologist, 1903, Transvaal. 

 X In the following paper the conception of isolysines is rather wide, and it would be better, 

 perhaps, to call the active substances in donkey serum which dissolve horse blood — heterolysines. 



