PIROPLASMA BIGEMINUM 



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Piroplasma gibsoni Patton, 1910. 



This Piroplasma has been found in dogs and in the jackal (Canis aureus) in 

 India by Patton. 



Morphology. — In films from the peripheral blood it is seen as small rings 

 o*i fjL in diameter, with one or two chromatin masses, of whicTi the second 

 is much smaller than the first, to which it is often joined by a pink thread. 

 Oval parasites, with a long amoeboid process, are also seen. 



Division. — Division is by binary fission, giving rise to a number of forms 

 enclosed in one leucocyte. 



Pathogenicity. — It causes one variety of canine piroplasmosis. 



Piroplasma bigeminura Smith and Kilborne, 1893, 



Synonyms. — Pyrosoma higeminum Smith and Kilborne, 1893; Apiosoma 

 higeminum Wandollek;5a&5sf-i hovis Chauvelot ; Ixodioplasma specificum hovum 

 Schmidt. 



P. higeminum is the cause of Texas fever in oxen, and appears as pyriform, 

 round, or amoeboid cells, and also as flagellate forms. It can be cultivated 

 on artificial media. 



Koch has traced the development in the tick, in whose gut the parasites 

 leave the red cell and become long and club-shaped, at the broad end of which 

 is found a round chromatin mass. From the club pseudopodia project. 



This club then becomes spherical, and immense numbers of amoeba-like 

 forms appear, which are said to grow into clubs. 



Pathogenesis. — The disease may exist in two forms, a grave and a benign. 



The usual symptoms of high fever, haemoglobinuria, icterus, anaemia, 

 paralysis, constipation, and death in a week or less, are exhibited in the grave 

 form, in which the mortality is 60 to 80 per cent. 



In the benign form there is anaemia without haemoglobinuria as a rule, 

 and the duration is about fourteen days. 



The disease can be spread by inoculation or naturally by the bites of in- 

 fected ticks — Margaropus australis Fuller in South America, Cuba, Porto 

 Rico, Australia, and the Philippines, and by M. decoloratus Koch in South 

 Africa. 



Post- Mortem.- — -The usual post-mortem signs are visible. 



Treatment. — There is no specific treatment. Kragerud advises intravenous 

 injections of i in 100 of protargol or formol, and afterwards a beverage of 

 10 grammes of lysol and carbolic acid in 500 grammes of distilled water. 



Lignieres recommends chloride of sodium and purgatives. Quinine has 

 also been advised. Nuttall and Hadwen s treatment should be tried. 



Piroplasma bovis Ba.bes, 1888. 



Synonyms. — Piroplasma annulatum Dschunkowsky and Liihe, 1888, Piro- 

 plasma higeminum Babes, Hcsmatococcus hovis Babes. 



P. hovis is the cause of red water or haemoglobinuric fever in European cattle 

 and in red deer {Cervus elaphus L..), and is spread by the tick Ixodes reduvius L. 

 and Margaropus annulaius Say. 



The disease produced may be acute or chronic. In the acute form about 

 90 per cent, of the red cells are infected by bacillary or ring-like parasites, 

 which cause high fever, quick pulse and respirations, seldom haemoglobinuria, 

 with convulsions and death in one or two weeks; or a chronic form, with 

 minute coccus-like parasites in 10 to 40 per cent, of the red cells, producing 

 weakness, jaundice, and anaemia. The post-mortem shows haemorrhages 

 into many organs. 



Piroplasma ovis Babes, 1880. 

 Synonyms. — Hcematococcus ovis Babes, Piroplasma ovis Lavcran. Amcebo- 

 sporidium polyphagum Bonome. 



P. ovis is found in sheep in Europe, Africa, and the West Indies, as large 

 intracorpuscular and extracorpuscular forms, and causes anaemia, haemoglo- 



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