EXPERIMENT STATION BULLETINS. 411 



Light. 1- 50 — complete. 

 1-100 — complete. 

 1-250 — complete. 

 1 500 — sediment considerable, quite cloudy. 



Dark. 1-10 — complete. 



1-20 — nearly complete, very slightly cloudy. 

 1-50 — sediment considerable, cloudy. 

 Check — no change. 



It will be seen from the agglutination tests that the agglutinative 

 power of the blood serum of the treated animal. Light, increased by 

 seven days after the injection of the first portion of living abortion 

 germs from 1-10 to 1-250, whereas the blood of the untreated heifer. 

 Dark, showed practically no change in agglutinative power. It is now 

 a well established fact that the agglutinative power of the blood serum 

 of animals affected with infectious abortion is increased. M'Fadyean 

 and Stockman originally demonstrated this in their work of vital im- 

 portance for the Committee of the British Board of Agriculture and 

 Fisheries in 1909.^ Later they bring a maturer judgment to criticize this 

 test favorably. In short, they state that "one will be justified in re- 

 garding complete agglutination with a serum dilution of 1-50 or 1-100 

 as strong evidence of infection. The blood serum of animals affected 

 with contagious abortion may agglutinate abortion bacilli in dilutions 

 of 1-800. As a rule, normal serum agglutinates at a dilution of not more 

 than 1-10.^ BriilP states that sound animals furnish a serum agglutina- 

 ting at 1-32, while habitual aborters furnish serum agglutinating at 1- 

 120 up to 1-1,600. The permanent value of this test must be furnished 

 by its extensive and critical use under varied conditions. 



On this same date, June 15, at 2 p. m., Light was injected as upon 

 the previous occasion with 130 c.c. of culture "MacNeal" one month 

 old, grow^n in the manner described above. The following temperature 

 records were made: 



It will be seen that the temperature reaction from the first injec- 

 tion began about 17 hours after the injection, reached its maximum 26 

 hours after the injection and resumed the normal condition only after 

 five and one-half days although it remained at an elevation of 103 or 

 above for only two days. After the second injection, the temperature 

 was found considerably elevated four hours after the injection, reaching 

 its maximum 28 hours after and resuming the normal condition three 

 days after the injection. 



