282 



parasite in India and Japan. The symptoms differ 

 in the following respects from those caused by 

 P. bigeminum : 



(i) Anaemia is only slight ; (2) Haemoglobinuria 

 is wanting ; (3) It is not transmissible by inoculation ; 

 (4) Cattle immunized against P. bigeminum are suscep- 

 tible to P. -parvum ; (5) The mortality is very high 

 ninety per cent, upwards. The incubation period is 

 about a fortnight. The duration after the appearance 

 of the first symptoms is about ten days. 



Fig. 92. P. parvum. Bacilli form t cross forms, and intracellular 

 protoplasmic masses 



Blood Examination. (i) In the early stages of the 

 disease bacilliform parasites and minute rings are found 

 in great abundance ; (2) Later large forms and pears 

 occur scantily ; (3) The arrangement of parasites in 

 the form of a cross is characteristic ; (4) The occur- 

 rence of protoplasmic masses (in size from one to three 

 red cells) containing numerous small chromatin 

 particles, in the endothelial cells of the spleen and 

 lymphatic glands (and occasionally in the blood) is also 

 characteristic (Fig>92). 



Post-mortem. (i) Great oedema of the lung 

 occurs in about a third of the cases ; (2) The lymphatic 



