An evaluation of strategic and short interval tick control in indigenous exotic and crossbred cattle.

The performance of Nguni, Bonsmara and Hereford oxen which were maintained free of ticks by short interval treatment with acaricide irrespective of tick load (tactical) was compared with similar groups which were treated for tick infestation only when the numbers of adult ticks on the cattle increased to moderately high proportions (strategic). Strategically treated Nguni oxen acquired a strong resistance against ticks and showed weight gains comparable with the tick free Nguni group. Weight gains in the Bonsmara group were higher in the strategically treated group suggesting a possible effect of the acaricide on the tick free group. Strategically treated Hereford oxen acquired heavy tick burdens and performed poorly compared with the tick free group. Practical approaches to strategic tick control under African conditions are discussed.