612 STATE BOARD OF AGRICULTURE. 



DISCUSSION. 



From the data presented in the foregoing pages, it is apparent first 

 of all, that the results have an important bearing upon the appearance 

 of agglutinating and complement fixing bodies in the blood of calves 

 as a result of ingesting naturally infected milk. The results show that 

 out of eleven calves fed upon naturally infected milk for a long period 

 of time, the blood of only one (calf 995 A, Table 2) developed comple- 

 ment fixing bodies to any marked degree. The calf was fed upon natural- 

 ly infected milk for thirteen weeks. The blood was tested at intervals 

 of about one week, by means of the agglutination and complement fixa- 

 tion tests. Complement fixing bodies were present in the blood for the 

 first five weeks. All succeeding tests have given negative reactions. It 

 is apparent that the blood of calf 102 A gave a weak positive reaction 

 after the feeding of milk was begun. The investigations of Cooledge (7) 

 seem to show that agglutinating and complement fixing antibodies for 

 Bad. abortus may be absorbed through the large intestine of humans 

 as a result of ingesting milk containing such antibodies. Talmon and 

 Castaigne (8) have demonstrated the appearance of agglutinating anti- 

 bodies in the blood of a child who was nursing a mother afi'ected with 

 typhoid fever. In a similar case they failed to demonstrate agglutinat- 

 ing antibodies in the blood of the child. Agglutinating antibodies were 

 present in the breast milk of the mothers. They account for the appear- 

 ance of antibodies in the first case from the fact that the child was 

 suffering from enteritis. They further state that antibodies are not ab- 

 sorbed by mucous cavities unless a lesion is present. The appearance 

 of antibodies in the blood of calf 102 A may be accounted for in a similar 

 manner, as this calf was suffering from a severe case of diarrhea at the 

 time antibodies made their first appearance. The remaining calves (ex- 

 cepting calf 100 A) fed upon naturally infected milk has never given a 

 positive reaction. The blood of calf 100 A was not tested until three 

 days after birth. Complement fixing bodies were present at this time. 

 This positive reaction is not due to an infection from the milk. This 

 statement is based on experiments of the writer which demonstrate the 

 time of appearance of agglutinating and complement fixing bodies for 

 Bad. abortus after subcutaneous injections of a live suspension of the 

 organisms. From eight to tAvelve days elapse before the appearance of 

 antibodies after an injection. 



The calves fed upon non-infected milk (excepting calf 1001 A) gave 

 no positive serum reactions. The blood serum of calf 1004 A possessed 

 complement fixing bodies at birth. The blood gave a positive reaction 

 for three succeeding weeks. 



It is evident from the results reported in Table 10, that antibodies 

 will develop in the blood of a calf when fed continually upon milk mixed 

 with a culture of Bad. abortus. The positive reaction does not persist 

 for a great length of time, but disappears while the mixture is being fed. 



Examination of Tables 6 and 12, reveals the fact that the blood sera 

 of calves may give a positive reaction at birth. The positive reaction 

 may be due to an active infection, or to a passive transmission of com- 

 plement fixing bodies present in the blood of the mother, to the fetus in 

 utero. Regarding the latter statement Pfoundler (5) says that anti- 

 bodies circulating in the body of the mother have not been proved to 



