Abstract:
Haemonchosis is considered to be the most economically important gastrointestinal disease of small
ruminants in the tropics and subtropics. However, chemical anthelmintics, which were the mainstay of
control, have been compromised by a high prevalence of resistance worldwide. Copper oxide wire
particles (COWP) have been shown to have anthelmintic effects, but few studies have examined their use
under field conditions. The use of COWP was therefore evaluated as a tactical anthelmintic treatment in
indigenous goats raised under communal farming conditions in Bergville, KwaZulu-Natal Province,
South Africa. At the beginning of the summer rainfall season (October 2007), the faecal egg counts of
172 female goats belonging to 15 farmers were determined and this sampling continued every four weeks
until the second week of January 2008. The goats within each of the 15 herds were ranked according to
their faecal egg counts for this week. The goats were sequentially paired off within each ranking starting
with those goats with the highest counts. One goat from each pair was randomly allocated to a treated or
control group. Two weeks later, a 4 g COWP bolus was randomly administered to each goat in the treated
group. Faecal egg counts were carried out on the goats two weeks following treatment, and the sampling
of the goats then proceeded every four weeks until October 2008. Except for the six-week period prior to
the administration of the COWP, the goats were examined according to the FAMACHA© system and
symptomatically treated with 12 mg/kg levamisole when anaemic. The percentage reduction in faecal egg
count due to the COWP treatment was 89.0%. Mean pre- and post-treatment faecal egg counts for the
COWP-treated group (n = 73) were 2347 eggs per gram of faeces (epg) and 264 epg, respectively. The
corresponding values for the untreated controls (n = 66) were 2652 epg and 2709 epg. The prevalence of
Haemonchus spp. larvae in pre- and post-treatment faecal cultures was 72% and 46%, respectively.
Symptomatic anthelmintic treatments in combination with mid-summer tactical treatments with COWP appear to be useful strategies for the control of Haemonchus contortus in indigenous goats in this farming
system and this approach could have application in other similar agro-ecological zones.
