Abstract:
On–host behaviour of Rhipicephalus appendiculatus was studied in the field in Bungoma
County in Kenya to evaluate the putative repellent effects of essential oils of Tagetes minuta
and Tithonia diversifolia at its predilection feeding site. Oils of both plants caused a
disruption of orientation, movement and attachment behaviour of ticks. More ticks dropped
off in the treatments with the two essential oils than with the control.
Treating the ear pinna with the essential oil of T. minuta caused the highest percentage of
ticks to drop off the host body. No tick reached the ear pinna treated with the essential oil of
T. minuta and up to 30% of ticks (from the forehead release site) reached the ear base. When
the ear pinna was treated with the essential oil of T. diversifolia, one tick reached the ear
pinna and up to 40% of ticks (from the dewlap release site) reached the ear base. The results
show that T. minuta repels ticks more strongly than T. diversifolia. However, both essential
oils offer possibilities for exploitation of potentially effective and environmentally acceptable
tools for on–host tick control.
Key words: cattle, feeding site, Kenya, on-host orientation behavior
