302 EXPERIMENT STATION RECORD. 



States. A historical at-count is given of the occurrence and distribution of the 

 disease in South Africa. Tlie organism of the disease is a species of pyroplasma 

 clo.sely related to that of Texas fever and exhibiting bacillary and coccal forms. 

 The organism was readily found in the blood of infected animals. The shortest 

 period of incubation observed was 10 days and the longest 20 days. The average 

 course of the fever occupied about 13 days, and the period from infection to death 

 about 25 days. The symptoms and post-mortem lesions are described in detail and 

 notes are given on the history of various cases and on extensive inoculation experi- 

 ments with the blood of affected animals. The tick which is believed to be instru- 

 mental in carrying the disease is RJdpieepJiahis sJnpleyi, commonly known as the 

 brown tick. Inoculation experiments were unsuccessful on account of the fact that 

 under ordinary circumstances tlie blood of affected animals does not produce the 

 disease when inoculat-ed into healthy ones. In a few instances it was observed that 

 animals which had recovered from one attack of Rhodesian tick fever were still 

 susceptible to the disease. 



The new form of redwater in the Transvaal, D. Hutcheon {Transvaal Ac/r. 

 Jour., 1 {1903), No. 3, pp. 45-57). — A brief account is presented of the work of Koch 

 and Theiler on this subject. Notes are also given on the history of the disease in 

 Rhodesia and the Transvaal. The disease is undoubtedly carried by ticks and the 

 author recommends quarantining known infected centers and the use of an arsenical 

 dip for the destruction of ticks. AVhile little good can be expected from the use of 

 drugs in the treatment of this disease, fairly satisfactory results have been observed 

 by the author in a number of cases from the use of carbolic acid and certain coal-tar 

 derivatives. Carbolic acid was given, thoroughly mixed with raw linseed oil. 

 Attention is called to the failure which has attended attempts to immunize cattle by 

 inoculation with the blood of animals recovered from Texas fever. It is necessary 

 to use blood from animals recovered from the more virulent form of the disease which 

 prevails in South Africa. 



Rinderpest and redwater in cattle, S. Stockman ( Transvaal Ayr. Jour., 1 {1903), 

 No. 4, PP- 59-63). — The author conducted an elaborate .series of experiments for the 

 purpose of determining whether animals could be infected with the.se 2 diseases 

 simultaneously and whether the lesions caused by the 2 diseases could be readily 

 distinguished. As a result of these investigations it was found that animals are fre- 

 quently attacked by both diseases at the same time, and that the extensive intestinal 

 lesions which had been attributed by some writers to an attack of redwater were 

 really the result of infection by rinderpest. During experiments made by the author 

 in the production of rinderpe.st serum a number of animals was inoculated with the 

 virus of rinderpest and one of these animals developed redwater in addition to rin- 

 derpest. Inoculation of other animals with the blood of these animals produced 

 rinderpest only in animals which were immune to redwater, while both diseases 

 developed in animals which were susceptible to both. The author concludes from 

 his experiments that the possible coexistence of rinderpest and redwater must be 

 admitted, and that this fact should be borne in mind in experiments with rinderpest 

 serum, or in inoculation experiments for the purpose of preventing redwater. 



Redwater inoculation, L. D. Gilson {Agr. Jour, and M'tn. Rec. INatal], 6 {1903), 

 No. 10, j)p. 310-313). — Excellent results are reported from inoculation experiments 

 during which the defibrinated blood of diseased animals was used for inoculating 

 susceptible animals. 



Virulent redwater in the Transvaal, D. Hutcheon [Agr. Jour. Cape Good 

 Hope, 23 {1903), No. 1, pp. 39-60). — The author presents a detailed report of his 

 investigations regarding the history, distriljution, cause, nature, and treatment of 

 the virulent form of Texas fever observed in the Transvaal. It is believed that this 

 disease is identical with that reported in Rhodesia. The author observed that cattle 

 which had been immunized against Texas fever were still subject to the virulent 



