Abstract:
Many studies on the population dynamics of questing ticks on pastures and of parasitic ticks
on cattle have been conducted. Few, however, have attempted to link the two in a single study.
This study aimed to assess the population dynamics of questing ixodid ticks on pastures and
of adult ticks on two breeds of cattle with different levels of susceptibility to tick infestation
on the same pastures. Between January 2005 and December 2009 questing ixodid ticks were
collected monthly from natural pastures at the Döhne Agricultural Development Institute and
at the adjacent Campagna Production System in the Amahlathi District, Eastern Cape province,
South Africa. Between February 2007 and January 2010 adult ticks were collected monthly
from Bonsmara and Nguni cattle grazing these pastures. Ten tick species were collected
from the pastures and 12 from the cattle. Significantly more questing larvae of Rhipicephalus
appendiculatus, Rhipicephalus decoloratus, Rhipicephalus evertsi evertsi and Rhipicephalus microplus
were recovered from the pastures grazed by Bonsmara cattle than from those grazed by Nguni
cattle (p ≤ 0.05). Significantly more adult Hyalomma rufipes, Rhipicephalus follis, R. appendiculatus,
R. decoloratus, R. evertsi evertsi and R. microplus were collected from the Bonsmara cattle than
from the Nguni cattle (p ≤ 0.05). The study showed that Nguni cattle are less susceptible to
tick infestation than are Bonsmara cattle and fewer questing ticks are collected from pastures
grazed by Nguni cattle than by Bonsmara cattle.