550 GENERAL THERAPEUTIC MEASURES 



have been isolated from cases of white scours in calves. The horses are 

 first treated with suspensions of dead organisms containing various strains 

 of B. coli, para-coli, meta-coli, abortus, aerogenes and enteritidis. After 

 this preparatory treatment, live cultures are injected intravenously into 

 the horses, beginning with small amounts until the highest tolerance is 

 reached. Then they are bled and again given a cycle of injections with 

 suspensions of the various live organisms. 



The standardization of anti-white scours serum is carried out by 

 taking samples of blood from the horses during the course of treatment 

 and the serum is subjected to the agglutination test against the various 

 strains used in the treatment. It is required that a potent serum should 

 agglutinate each respective strain in a dilution of at least 1 :1500. It has 

 been found that serum possessing such an agglutinating titer against the 

 different strains possesses prophylactic and curative value for white scours 

 of calves. 



It is, of course, necessary that such serum should possess polyvalent 

 properties, since it is well known that different strains of the colon and 

 other germs are responsible for the disease, and if the serum has been 

 prepared only against a particular strain it would exert only slight influ- 

 ence against the other disease-producing strains. 



In the preparation of the horses producing anti-white scours serum 

 a great number of strains of the colon and para-colon group are being 

 used; also strains of abortion, aerogenes and meta-colon bacilli, since 

 it has been found ,that at times some of these organisms are associated 

 with white scours in calves. Repeated observations made by investi- 

 gators abroad and also in this country have shown that the systematic 

 treatment with potent serum results in the elimination of loss from this 

 infection even in the most severe infections, where prior to this procedure 

 the losses in calves amounted to from 75 to 100 per cent. Sanitary meas- 

 ures should necessarily be carried out in order to eradicate the infection 

 from the premises. 



In herds where the disease is prevalent it is essential to administer 

 to each calf as soon as possible after birth a protective dose of the serum. 



The following statement is made by Williams on the use and effec- 

 tiveness of anti-white scours serum: 



"In herds wliere abortion, premature birth, retained after-birth, and 

 scours, are common it is better that the calf should have liberal doses of 

 calf-scours serum before it has its first feed. Usually it is well to give 

 twenty mils immediately after scours set in ; the calf may take twenty to 

 thirty mils of serum every four to six hours if required. The enemas of 

 warm salt solution repeated ever four to six hours aid also." 



Other Indications for Specific Bacterin Therapy. 



Aside from the diseases described in which biological products have 

 proved efficacious, there are numerous other conditions in which the em- 

 ployment of bacterial vaccines have given encouraging results. Follow- 

 ing the exploitation of the vaccine therapy by Wright, bacterins have been 

 prepared for practically all conditions in which micro-organisms are asso- 

 ciated with the pathological processes. Among these the pyogenic affec- 

 tions have commanded special attention, as these conditions are especially 

 promising to yield to such specific therapy. 



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