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Chapter XXVI 



GENUS PIROPLASMA 



Piroplasma.* (= Babesia) are intra-corpuscular 

 parasites, frequently pear-shaped as trie generic name 

 implies. They do not produce pigment, and multiply 

 in the blood by dividing into two, and are transmitted 

 by ticks, the transmission being sometimes hereditary ; 

 i.e., the mother tick feeding on a sick animal transmits 

 the disease to some stage of her progeny, or the trans- 

 mission is only from stage to stage, e.g.^ from larva to 

 nymph or nymph to adult. 



I . P. bigeminum. This disease of cattle, perhaps 

 best known as Texas fever, is world-wide in its distri- 

 bution. Infection may be latent with few or no 

 symptoms. The acute form is characterised by : 

 (i) High temperature ; (2) Haemoglobinuria in about 

 eighty per cent, of cases, which, as in other forms of 

 Piroplasma, may cease after some days ; (3) Icterus 

 often absent ; (4) Anaemia, often extreme ; 

 (5) Muscular palsies, staggering gait and other nervous 

 symptoms ; (6) Constipation followed by bloody 

 diarrhoea is not uncommon ; (7) Death in a week or 

 less ; (8) The mortality is from sixty to eighty per cent. 

 In the benign form of the disease there is anaemia, 

 generally an absence of haemoglobinuria, and the 

 duration is about a fortnight. 



Blood Examination. Obtain blood by pricking the 

 snout or a small vein in the ear. Generally one per 



* Those Piroplasmata shewing bacillary forms are placed by some authors in 

 a new genus Theileria ; so that we should then have T. mutatis, T. annulata, T. eqvi, 

 T. parva, T. cervi. 



