XII, B, 6 Boynton: Diseases in Cattle 287 



immunity against anaplasmosis. In further experiments Theiler 

 proved that animals recovering from anaplasma infection were 

 not immune to B. bigemina either by means of ticks or by blood 

 inoculation. He suggests that in inoculating with B. bigemina 

 for the purpose of immunization it is just as well to inoculate 

 with anaplasma at the same time. The inoculation period of 

 B. bigemina is so much shorter, tliat the animal will have ample 

 time to recover before the anaplasma reaction takes place. 



He has also proved that animals recovering from Babesia bi- 

 gemina and anaplasmosis can be easily infected with Babesia 

 mutant, which shows that no immunity is conferred either sepa- 

 rately or together against B. mutans. 



Theiler proves that two varieties of tick can transmit the 

 disease : Boophilus decoloratus, the blue tick, which also transmits 

 Babesia bigemina, and the black-pitted tick, Rhipicephalns simiis. 



Frequently a double infection of Anaplasma marginale and A. 

 centrale is found in the same animal, this being especially true 

 after tick infections. 



The three cases herein mentioned are the only ones which have 

 come to any notice during the past twenty months. Further 

 developments of the disease have been awaited, in order to obtain 

 a better insight concerning its etiology, modes of infection, 

 pathology, etc., but with no success, which leaves this paper 

 merely a narrative discussing three cases that gave pictures 

 similar to those described by Theiler and by Sieber as anaplasma 

 infection. This creates a doubt as to whether that disease really 

 exists in the Philippine Islands, or whether these animals suffered 

 from some other ailment which brought about the formation 

 of these anaplasmalike bodies in the red blood cells. 



On studying the literature, it is found that bodies similar to 

 anaplasma may be produced artificially. Very creditable work 

 has been done by Dias and Aragao,(2) in which instance they 

 were able to produce anaplasmalike bodies in dogs, rabbits, and 

 guinea pigs by injecting them subcutaneously with small doses 

 of phenylhydrazine. They were also able to produce a similar 

 condition in rabbits by injecting them subcutaneously with small 

 doses of nitrobenzol, a similar condition in dogs by injecting 

 them subcutaneously with small doses of pyrogallic acid, and a 

 similar condition in calves by injecting them with a series of 

 fairly large doses of trypan blue. 



In considering these results, there arises a doubt as to whether 

 this was the infectious disease designated by Theiler as ana- 

 plasmosis, or whether it was the result of some other infectious 

 or noninfectious disorder from which the above-mentioned an- 



