Abstract:
The Northwestern region of Ethiopia is affected by both tsetse and non-tsetse transmitted
trypanosomosis with a significant impact on livestock productivity. The control of
trypanosomosis in Ethiopia relies on either curative or prophylactic treatment of animals
with diminazene aceturate (DA) or isometamidium chloride (ISM). In the present work; questionnaire
survey, cross-sectional and experimental studies were carried out to; a) assess the
utilization of trypanocidal drugs; b) determine the prevalence of bovine trypanosomosis and;
c) assess the drug resistant problems respectively in Tsetse and non-tsetse infested areas on
NW Ethiopia. A total of 100 respondents were included for the survey and the questionnaires
focused on the drug utilization practices for the control of Trypanosomosis. Blood from cattle
640 (324 cattle tested in 2011, 316 cattle tested in 2012) and 795 (390 cattle tested in
2011, 405 cattle tested in 2012) were examined from tsetse infested and non-tsetse infested
areas respectively using the buffy coat technique and thin blood smear for the detection of trypanosomes
and measurement of packed cell volume (PCV). For the assessment of trypanocidal
drug resistance three isolates, one from tsetse (TT) and two from non-tsetse (NT) areas were
used on thirty six trypanosome naïve calves. The experimental animals were divided randomly
into six groups of six animals (TT-ETBS2-DA, TT-ETBS2-ISM, NT-ETBD2-DA, NT-ETBD2-ISM, NTETBD3-
DA and NT-ETBD3-ISM), which were infected with T. vivax isolated from a tsetseinfested
or non-tsetse infested area with 2 × 106 trypanosomes from donor animals, and in
each case treated with higher dose of DA or ISM. The results of the questionnaire survey
showed trypanosomosis was a significant animal health constraint for 84% and 100% of the
farmers questioned in non-tsetse and tsetse infested areas of Northwest Ethiopia respectively.
Responses on trypanocidal drug utilization practices indicated that risk factors for the development
of drug resistance are common and treatment failures are frequently seen. Accordingly,
the majority of farmers in tsetse infested area get trypanocides from drug stores and unauthorized
sources whereas those from non-tsetse area get from veterinary clinics. Moreover, treatment
administration is mainly by animal health personnel and treatment frequency is a
maximum of three times/year/animal in non-tsetse area whereas it is administered mainly
by the farmers more than seven times/year/animal in tsetse infested area. The prevalence of
