66 



What is the Importance of Piroplasma ? 



Piroplasma (syn. Babesia bigeminum) is the parasite of 

 Redwater or Texas cattle-fever. 



How is Babesia transmitted from an Infected Ox to a 

 Healthy One ? 



By one of the Ticks, Bhipicephalus annulatus (syn. 

 Boophilus bovis). 



What is the History of the Tick, Boophilus, in relation to 

 Texas Cattle-fever? 



The ticks feed on the blood of the ox. After their last 

 moult they pair. The fertilised females, gorged with 

 blood, drop off the ox. About 2000 eggs may be laid by 

 one female. Along with the egg in the egg-case there is 

 a supply of blood for the developing larva. When the 

 young tick hatches out, it has some of this blood in re- 

 serve within its abdomen. It crawls up a grass blade, 

 and if it fails to attach itself to the skin of an ox before 

 "the remains of its share of its mother's last meal" are 

 exhausted, it dies. If the mother drew the blood from 

 an infected ox, the young ticks are infected, and so healthy 

 cattle " bitten " by them become infected. 



What are the Chief Features of the Hcemosporidia? 



They are intracellular parasites of the blood of Am- 

 phibians, Reptiles, Birds, and Mammals, including Man. 



The life-cycle shows alternation of generations repeated 

 generations asexual by schizogony, which serve to multiply 

 the parasite within its host, are followed by sexual genera- 

 tion (formation of gametes which conjugate to form the 

 zygote or sporont). 



The sporont, at first motile, encysts, becomes an oocyst 

 .from which by sporogony numerous minute naked sporo- 

 zoites are developed. The sexual cycle occurs in the inter- 

 mediate host, an invertebrate animal of blood-sucking 

 habit which inoculates new vertebrate hosts. 



The parasites cause fevers of various kinds. In Man 



