VETERINARY MEDICINE. 585 



parasites take up within the red corpuscle; (2) on tlie difference in size, there 

 being slightly smaller individuals in the centrale variety; (3) on the different 

 virulency, the centrale variety having caused neither death nor any serious 

 lesions; (4) on the fact that a recovery from an infection from A. centrale does 

 not cause complete immunity. 



"Anaplasmosis was transmitted in 4 instances by means of BoopJiilus dccol- 

 oratiis larvje. and once by Rhipicephalus simus larvse, the mothers of which 

 ticks were collected off immune animals. The incubation times after tick in- 

 fection varied from between a few days under 2 months to a few days over 3 

 months. It has been noticed in one case (heifer 935) that when a very heavy 

 infestation of ticks is made, an animal may die as a result of loss of blood 

 due to the I'epletion of the engorged females. 



" The A. centrale infection, transmitted either by ticks or by inoculation, in 

 no instance caused the death of any of the 39 English heifers. Accordingly, 

 an inoculation with A. marginale centrale can be made use of as a practical 

 method of inoculation against anaplasmosis. Recovery from A. centrale infec- 

 tion gives so much protection that a subsequent inoculation of A. marginale no 

 longer causes death or any serious lesions. 



"Animals which were immune to Bahesia bigemina could easily be infected 

 with anaplasmosis, either by means of ticks or by injection of blood. Animals 

 which were immune to anaplasma infection could easily be infected with 

 Babesia blgemma, either by means of ticks or by blood inoculation. Injected 

 animals can be exposed to natural infection before the A. centrale reaction has 

 run its course. The anaplasmosis infection due to ticks having a long incuba- 

 tion time (55 to 100 days) will not develop sevei'ely in the inoculated animal, 

 in which the disease runs with a shorter incubation time (16 to 40 days). All 

 animals which have passed through an attack of anaplasmosis and redwater 

 conveyed by inoculation and exposed to natural infection for over a year are 

 still alive. 



" The anaplasmosis transmitted by ticks was that of the type centrale and 

 marginale. To judge by the blood smears obtained from the cattle exposed in 

 the veld, a double infection is frequently met with. Animals immune to A7ia- 

 plasma and Babesia bigemina infections could easily be infected with B. mutans. 

 As an accidental occurrence in some instances the larval ticks of Boophilus. 

 collected off immune cattle, transmitted an infection of Spirochceta theileri in 

 typical time. In one instance the inoculation with blood of a horse in which 

 the spirochetes were noted, the pure infection was transmitted to a susceptible 

 animal. 



" For the requirements of the conditions of South Africa, it is necessary to 

 combine the immunization against anaplasmosis with an inoculation against 

 redwater. The redwater inoculation can be done befoi'e or after the ana- 

 plasmosis inoculation, but it is practical to do both at the same time. The 

 redwater having a shorter incubation time will develop first and. a recovery 

 will usually be effected before the anaplasmosis reaction sets in. In applying 

 this method to the practice, it is necessary to keep the animal during the red- 

 water reaction (about 15 days) under close observation and to check any 

 unusual reaction by means of a trypanblue injection, and while the animal is 

 imdergoing the anaplasmosis reaction it will have to be well fed." 



Contributions to the diagnosis of infectious abortion in bovines, Z. Beuxl 

 {Berlin. Tierdrztl. Wchnschr., 21 (1911), No. J,0, pp. 721-727).— The serum ob- 

 tained from sound animals showed agglutinations in a titer of 1 : 32, while 

 animals which habitually aborted agglutinated the Bacillns abortus with few 

 exceptions in titers varying from 1 : 120 to 1 : 1,600. The agglutination test is, 

 therefore, deemed a valuable diagnostic aid for this condition. 



