TICKS 



The nymph, after feeding on the blood of the host 

 and increasing its size, moults its skin and appears 

 as a sexually mature tick. The female is fertilised by 

 the male while she is still small. She sucks the blood 

 of her host until she becomes greatly distended. She 

 then lets go her hold and falls to the ground and 

 proceeds to lay her eggs. 



Ticks are the chief agents in spreading stock 

 diseases. If ticks were exterminated we should prac- 

 tically stamp out stock diseases. Apart from the 

 terrible losses of stock animals by infection spread 

 by ticks, these terrible pests cause severe irritation, 

 loss of blood, and consequent loss of condition in 

 animals. 



Birds feed upon ticks in every phase of their life 

 history. Quails, larks, and other birds seek out the 

 clusters of eggs and devour them. Other species of 

 birds pluck ticks from their host or feed upon the 

 gorged females on the ground. Numbers of birds, 

 chiefly starlings, associate with cattle in order to secure 

 these blood and egg laden female ticks when they fall 

 from the cattle. A single female tick is indirectly 

 capable of infecting an entire district in a short time 

 with one of the many cattle plagues. 



Every gorged female tick eaten by a bird is the 

 potential parent of from 2,000 to 18,000 ticks, each 

 individual of which may be capable of infecting a 

 stock animal with a highly virulent disease. It will 

 therefore be seen what an important part the bird 

 plays in stock rearing. 



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