7g4 Gall Sickness. 



Mixeil infections occur especially frequently with redwater. According to 

 Theiler's view, Texas fever, as it has been formerly described, constitutes two 

 different diseases, namely the Texas fever in the restricted sense (piroplasmosis, 

 redwater), and the gall' sickness (anaplasmosis). As the Piroplasma bigeminum 

 and the Anaplasma marginale occur \ery frequently simultaneously in the same 

 animal, the development of redwater with piroplasma in the blood is first observed 

 after an inoculation of blood; when the animal has recovered and the time of 

 incubation for the anaplasmosis has elapsed a new disease results, which was for- 

 merly considered as a relapse of redwater. Mixed infections occur also with 

 Piroplasma mutaus, and with iSpirochacta theileri. 



The symptoms of gall sickness are high fever with great debility, 

 labored respiration, and very frecjuent heart's action. Constipation or 

 diarrhea, fnrther moderate swelling of the eyelids, with lachrymation. 

 Edematous swellings may also appear in different parts of the body ; in 

 the later course, anemia and icterus is observed, when the animals rap- 

 idly become emaciated. Some animals die Avithin a few days, others in 

 1-2 Aveeks; the greater part of the patients, fre(iuently even 80-90% 

 recover, but outl)reaks with losses up to 50% may occur (Leipziger). 



According to the course of the disease a more or less rapid multipli- 

 cation of anaplasma, with a corresponding reduction in the number of 

 erythrocytes is found in the l)lood at the beginning of the fever. Pale- 

 ness of the remaining blood corpuscles is observed, and in less acute 

 cases polychromatophilia, and basophilia, still later the appearance of 

 normoblasts. 



The anatomical changes consist in pronounced anemia and icterus, 

 moderate gastro-intestinal catarrh, diffuse swelling of the lymph glands, 

 acute spleen tumor with reddish-brown, soft but not liquefied pulp, small 

 hemorrhages and degeneration of the heart muscles. 



For the prevention of the disease it is aimed to keep animals from 

 marshy pastures, especially from overgrown banks of rivers. If the 

 disease has already appeared it usually subsides after the herd is driven 

 to a dry elevation. 



Literature. Edington, Comp. Path., 1905. XYIII. 155. — Theiler, ibid., 

 1907. XX. 1; Z. f. Infkr., 1910. VIII. 39. — Spreull, ibid. 1908. XXI. 193. — 

 Leipziger, D. t. W.. 1910. 150. 



(c) Piroplasmosis of Horses. Piroplasmosis Equorum. 



(Biliary fever; Babesiosis equi; Pferdemalaria {German^; 

 Piroplasmose equine [French'].) 



History. Guglielmi (1889) in Italy found in the red blood corpus- 

 cles of horses parasites resembling the piroplasma bigeminum, Itut the 

 disease has become better known only since the study of fhe South Afri- 

 can horse sickness (see p. 285). Although Rickmann still considered the 

 blood parasites as the cause of this affection, Theiler proved that in 

 South Africa there exists another disease of horses which may fre- 

 (piently be complicated with the latter ; the same author also established 

 more closely the symptomatology, and pathological anatomy of piro- 

 plasmosis of horses, and recently showed also its .identity with a 

 similar affection of mules and donkeys. The parasites were also studied 

 by Laveran, Koch and Marzinowski, while Italian, English, French and 

 Russian veterinarians contributed especially descriptions of its spread 

 and symptomatology. 



