Abstract

The immunological mechanisms of acquired resistance to ticks have been studied with a number of tick species using both laboratory and domestic animals as hosts. No simple, general mechanism for resistance has been discovered though some factors are frequently, but not invariably, observed. The most notable of these are the infiltration of granulocytes (basophils, eosinophils or neutrophils) into the feeding lesion, the involvement of mast cells and the deleterious effect of histamine on ticks.
The ability of cattle to acquire resistance to Boophilus microplus is known to be heritable, though the genetics are not understood. '
Finally, it has recently been shown that an immunity to Boophilus microplus which is different to that acquired naturally can be induced using "concealed antigens". Whether genetic variability will be an important factor in exploitation of this form of immunological control of ticks is quite unknown.
 

P. Willadsen

Proceedings of the World Congress on Genetics Applied to Livestock Production, Volume XI. Genetics of reproduction, lactation, growth, adaptation, disease, and parasite resistance., , 571–580, 1986