Abstract:
A survey of the prevalence, predilection sites and skin lesions caused by Ixodid ticks of small ruminants in Gboko L.G.A. of Benue State was undertaken for a period of 12 months spanning both the dry and rainy seasons. Body ticks were collected physically from each animal examined while blood samples were obtained by jugular venipuncture. Data were also collected on the sex, age, body temperature and species of the animals examined. Meteorological data for Gboko area was obtained for the period. The blood samples were examined for haemoparasites using routine techniques while the Packed Cell Volume (PCV) was estimated by the Haematocrit Centrifugation Technique (HCT). Prevalence of tick species in sheep and goats was 12.01% and 21.48% respectively. The species of ticks collected included Amblyomma variegatum (57.65%), Boophilus species (34.60%), Rhipicephalus sanguineus (4.75%), Hyalomma truncatum (2.23%) and H. rufipes (0.79%), in descending order of abundance. The preferred sites of attachment of ticks were areas with thin skin and sparse hair. There was a high correlation (r = 0.86; P < 0.05) between tick population and rainfall. Prevalence of tick infestation and rainfall was also highly correlated (r = 0.75; P < 0.05). Generally, more ticks were collected during the wet season (85.04%) than the dry season (14.96%). Incidence rates of tick infestation was highly variable (0 – 70%). The proportion of adult animals infested with ticks was significantly higher than that of young (P ≤ 0.05; x2 =16.3) and goats than sheep (P ≤ 0.5; x2 = 60.11). Tick infestation was more on females than males (P ≤ 0.05; x2 =118.42). No important tick-borne haemoprotozoan parasite was detected in the animals. It is possible that these breeds of sheep and goats in this ecological zone have developed resistance to Babesia and Anaplasma species. Prevalence of infection with Trypanosomes was 4.8%. Two species of Trypanosomes were detected. Of these T. brucei predominated T. vivax infection. The infected animals with Trypanosome had a significantly (P < 0.05) lower PCV than the non-infected. The mean PCV values for sheep and goats examined were 21.5% and 22.6% respectively. Mean rectal temperature of goats and sheep examined were 38.9 + 2.40C and 37.80 + 3.70C respectively. Skin lesions seen at sites of attachment of ticks were scars, abscesses and skin necrosis. Tick paralysis was found in 0.01% and 0.02% of sheep and goats respectively. Lameness was recorded in 0.05% of sheep and 0.02% of goats examined. These results suggest that goats and to a lesser extent sheep are important hosts of various tick species in the area of study and it is necessary to include them in any tick control programs for livestock in the area.
