778 Piroplasmosis of Cattle. 



were the immunizations in Texas, where up to the end of 1901 out of 1,251 immun- 

 ized cattle 116 or 9.2% died later; likewise in Australia (Queensland, where immun- 

 ization of 35,000 cattle caused a loss of 3-4%, and besides, of 17,960 immunifed 

 animals 679, that is 3.6% succumbed later to the natural infection. But in one 

 experiment, out of 95 previously immunized animals all remained healthy after 

 attaching ticks to them, while 30 non-immune cattle became affected as a result 

 of it. 



Technique of Immunization. Tor the inoculation, blood is taken from the 

 jugular vein of cattle which have passed through a natural or artificial affection about 

 two months previously. The blood is defibrinated, and either used immediately or 

 kept in the ice chest until the inoculation. According to Kolle, blood containing 

 parasites from calves reared in infected localities is best adapted, according to 

 Schiitz blood from artificially infected calves which have recovered at least within 

 83 days. Three ee. of the defibrinated blood are injected subcutaneously, and if 

 possible the operation should be undertaken during the winter or at the beginning 

 of spring. It is best to undertake the inoculation on calves. Cows in advanced 

 pregnancy, poorly nourished, or in general animals which are not entirely well 

 should not be immunized. 



The immunized animals should be kept in the stable for three weeks and fed 

 moderately before they are driven to pasture. 



Other Methods of Immunization. Dalrymple, Morgan & Dodson 

 also obtained satisfactory results in America, by taking from the body 

 of affected animals ticks sucked full with blood, grinding them, and inoc- 

 ulating cattle subcutaneously with the material, while Connaway & 

 Francis, in America, recommended the application of infected larvae 

 or nymphs (the first time 20-50, after a month again 200-400) on the 

 skin of healthy animals. 



Lignieres produces vaccine by cultivating ( 1) the piroplasma in 

 defibrinated blood from affected animals, which produce in healthy 

 cattle only a very mild affection at the same time immunizing them (the 

 immunization requires three inoculations. The experiments carried out 

 in Buenos Aires and Alfort gave satisfactory results, as immunized 

 cattle resisted artificial as well as natural infections, but there are no 

 reports available relative to its application in practice. The method 

 of preparing the vaccine is likewise unknown. 



Blood seruin of cattle which have recovered from the disease is 

 not suitable for the immunization of cattle. 



Literature. Babes, C. B., 1888. OVII. 692; V. A., 1889. CXV. 81. Smith & 

 Kilborne, An. Ind., 1893. Bull. Nr. 1. — Theiler, Schw. A., 1895. XXXVII. 3; 

 Fortschr. d. Vhyg., 1903. I. 133; V. J., 1910. 98; Bull. Soe. Path, exot., 1910. III. 

 135. — Ligniferes, La tristeza, etc., Buenos Aires 1900; Arch, de paras., 1903. VII. 

 398. — Kossel & Weber, Arb. d. G.-A., 1900. XVII. 460. — Techn. Dep. f. i. Vet. — 

 Wesen. A. f. Tk., 1901. XXVII. 41. — Krageriid, Z. f. Tm., 1901. V. 284. — 

 Kossel, Hb. d. p. M., 1903. I. 840 (Lit.). — Kossel & Schutz, Weber & Miessnev, 

 Arb. d. G.-A., 1904. XX. 1. — Schmidt, A. f. Tk., 1904. XXX. 42. — Knuth, Diss. 

 Leipzig 1905. — Koch, Z. f. Hyg., 1906. LIV. 1. — Evers, B. t. W., 1908. 458. — 

 Witt, ibid., 1908. 628. — Nuttall & Hadwen, ibid., 1910. 38. 



(b) East African Coast Fever. 



(East coast fever, Rhodesian redwater, Rhodesian tick fever;' 

 Ostafrikanisches Kustenfieber [German].) 



This dangerous form of piroplasmosis in cattle is dis- 

 tinguislied from the previously described affection especially 

 in that it cannot be transmitted from animal to animal by 

 the blood. Its cause is the Piroplasma parvum. 



