Georgia State College of Agriculture 



Parasites of Cattle 



EXTERNAL PARASITES. 



Cattle Ticks. 



Full grown female ready 

 eggs. 



The cattle tick, Margaropus An- 

 nulatus, formerly known as Bo- 

 ophilus Annalutus, must be studied 

 and its life history or cycle under- 

 stood in order that the methods 

 recommended for eradication may 

 be intelligently followed. 



The host of the tick is the cow 

 or other animal of the Bovine spe- 

 cies. Occasionally specimens of the 

 cattle tick are found on other ani- 

 mals as horses and mules, but in 

 these animals it does not produce 

 disease. There are also other ticks, 

 such as the "wood tick," or "ear 

 tick," which are sometimes found 



on horses, mules, and dogs, but these ticks are not known to cause 



disease in any animal. 



In studying the life history of the tick, Margaropus Annulatus, it 



is best to begin with the engorged female as she releases her hold on 



the cow and drops to the ground for the purpose of laying eggs. 



The tick at this stage has attained 

 the maximum size and is about one- 

 half inch long by three-eights inch 

 broad and one-fourth inch thick. 

 Having dropped to the ground she 

 may be eaten by birds or ants, or 

 may be destroyed by cold. If not 

 destroyed, egg laying begins in a 

 few days in warm weather, or in 

 a longer time in cold weather. 

 Graybill, U. S. D. A., Farmers' 

 Bulletin No. 378, gives his observa- 

 tions as from two to twenty days 

 in spring, summer, and fall, and 13 

 to 98 days in winter. 



The eggs are small roundish 

 bodies of brownish or reddish color, 

 about one-fiftieth inch in diameter, 

 and are held together by a sticky 

 substance secreted by the tick. 

 The mature female lays a variable 

 number of eggs, from several hundred to from three to five thousand. 



Tick laying eggs. 



