TICKS AND CONTROL METHODS

Ticks are the most important ectoparasites of livestock in tropical an d sub-tropical areas, and are responsible for severe economic losses b oth through the direct effects of blood sucking and indirectly as vect ors of pathogens and toxins. Feeding by large numbers of ticks causes reduction in live weight gain and anaemia among domestic animals, whil e tick bites also reduce the quality of hides. However, the major loss es caused by ticks are due to the ability to transmit protozoan, ricke ttsial and viral diseases of livestock, which are of great economic im portance world-wide. The authors review general aspects of tick biolog y, the taxonomy, pathogenic effects and vector role of these species, and methods for the control of ticks. The distribution of ticks is con tinuously changing, as illustrated by the spread of the African tick A mblyomma variegatum in the Caribbean, where a large-scale eradication campaign is now under way.