i86 SOME MINUTE ANIMAL PARASITES 



which have been successfully treated, the recovered 

 animals become " salted " in other words, they still 

 harbour a few parasites in their blood. The treat- 

 ment of cattle is, then, of service in obtaining 

 " salted " animals, which will resist re-infection when 

 taken into infected areas. Patton, in India, has 

 cured a piroplasmosis among the hunt-dogs of 

 Madras by salvarsan, but it has not yet been applied 

 to domestic animals. 



Preventive measures should be considered. These, 

 while troublesome, have been effective when well 

 carried out. Dips of many varieties are of use for 

 spraying sheep or cattle, or literally " dipping " 

 them, but success is only partial, as ticks around 

 the head and in the ears are not attacked, while 

 others are rendered only partially insensible. The 

 use of dips, followed by hand-picking, is of service 

 in cases where the numbers of cattle are limited. 

 But the animals in these cases must be kept off the 

 pasture, for larval and nymphal ticks in varying 

 degrees of infectivity may be there. In America it 

 has been found that absence of cattle from infected 

 pastures for a few months causes the death of young 

 ticks by starvation. Should older ones be present, 

 they may remain alive for some time without feed- 

 ing. The use of gas-lime on pastures is certainly 

 somewhat of a deterrent, but burning the pasture 

 appears to be the most efficacious means of clearing 

 the tick pest. 



The movement of cattle from tick-infested to tick- 

 free areas must be under strict control. In South 

 Africa a huge " tick belt " stretches across the 



