366 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



the more attenuated and for the second vaccination the less attenu- 

 ated vaccine beini; injected. The rabbits received 0.2 c. c. per injec- 

 tion, ^vhile the sheep were given 0.7 c, c. of each vaccine. On the 

 sixth day following the second injection the animals were given a 

 subcutaneous injection of the pure culture of the Bacillus bipolaris 

 bubalisepticvs. Likewise a rabbit and one sheep which had not been 

 vaccinated were also injected with the pure culture of the organism, 

 serving as controls. Neither the two vaccinated sheep nor the vacci- 

 nated rabbits developed any indications of the disease, only one 

 sheep showing a slight elevation in temperature, which subsided 

 after one day; on the other hand, the control animals succumbed to 

 the disease. 



After obtaining these favorable results the vaccine was sent to the 

 veterinarian entrusted with the vaccination of the buffaloes, with 

 instructions to vaccinate all animals of the herd by the same pro- 

 cedure at 10-day intervals. The dose for each animal was 1 c. c. of 

 the vaccine. Following vaccination the herd was carefully ob- 

 served, no immediate effects being noticed from the vaccination, and 

 u]) to the present time there has been no indication of the recurrence 

 of the disease among the buffaloes. 



In the progress of the preparation of the vaccine, experiments 

 were also conducted in the laborator}^ to determine whether the com- 

 plement-fixation test could be applied for the diagnosis of the dis- 

 ease, and also for the purpose of determining the relative degree of 

 immunity conferred on the vaccinated animals in artificial immuni- 

 zations. An antigen was prepared from the original organism recov- 

 ered from the outbreak among the buffaloes in the form of a shake 

 extract. The hemolytic system consisted of sensitized rabbit serum 

 (amboceptor), guinea-pig serum (complement), and washed-sheep 

 corpuscles. The test Avas employed Avith sheep serum and rabbit 

 serum of artificially infected animals, and the results proved entirely 

 satisfactory. A complete fixation was obtained in all instances when 

 applied to 0.1 c. c. of serum of infected animals, while the control 

 showed no fixation whatsoever. 



After the vaccination of the sheep' and rabbits, blood serum was 

 obtained from these animals and tested with the complement-fixation 

 test. The results in these instances also showed a fixation of the 

 complement, although not as complete as in the infected animals, 

 nevertheless showing that the animals responded after vaccination 

 with the production of immune bodies. This reaction has been noted 

 even two months after the vaccination, and the testing of the blood 

 will be continued from time to time in order to determine the length 

 of the period in which the animals possess immune bodies subsequent 

 to vaccination. 



The utilization of the complement-fixation test in the diagnosis of 

 of hemorrhagic septicemia, and also its value in determining the rela- 

 tive immunity established by vaccination, is of great importance, not 

 alone in this disease but also by its possibility of utilization in other 

 diseases. 



RABIES. 



During the year ending June 30, 1912, there were 183 animals, 

 consisting of 150 dogs, 20 cats, 8 cattle, and 5 Jiorses or mules, sus- 

 pected 01 being affected with rabies, sent to the pathological labora- 



