290 



containing each i c.c. of normal salt solution. When 

 parasites are abundant in the blood, chloroform a dog 

 and take blood from the heart. Defibrinate by 

 shaking up in a sterile bottle with pieces of glass, 

 wire, etc. To each tube of salt solution add c.c. of 

 defibrinated blood. Keep at about 27. Examine 

 next day. Stellate forms are described by Kleine 

 similar to those seen by Koch in ticks (p. 281). These 

 subsequently become spherical. Fiilleborn, on the 

 contrary, describes flagellates in culture. 



7. P. ovis. Occurs in Europe, Africa and West 

 Indies. The disease is characterised by (i) Intense 

 anaemia, the number of blood cells falling from eight 

 to one million ; (2) Haemoglobinuria, the urine 

 contains also red cells and bile pigment ; (3) Bloody 

 diarrhoea ; (4) A mortality of about 50 per cent. 

 On the other hand the symptoms may be exceedingly 

 slight. 



Blood Examination. Fairly large intracorpuscular 

 and extracorpuscular forms occur. 



Post-mortem. The tissues are very oedematous: 

 The spleen is enlarged. The liver especially, and the 

 kidneys shew marked inflammatory changes. The 

 gut is inflamed and ulcerated. 



Transmission. (i) By inoculation ; (2) Eu. bursa 

 is the carrier in Hungary. As in P. canis, it is only 

 the adult tick, the daughter of an infected mother, 

 that conveys the disease. The incubation period is 

 about seven days. It is uncertain whether the blood of 

 recovered sheep is infective. 



Eu. tursa 



Adults take infection from a sick sheep. Drop on to 

 the ground and lay eggs which develop into 



