Abstract:
Background: Tsetse-borne African Animal Trypanosomosis (AAT) greatly influences
livestock distribution and significantly slows livestock productivity in sub-Saharan Africa.
While a number of control methods targeting the vector tsetse are in field application,
treatment with the few available trypanocides continues to be the most widely applied
control method. Unfortunately, improper and frequent use of these few available drugs,
accelerated by poor veterinary service delivery, promote trypanosome drug resistance, the
magnitude of which has not been delineated. In the present study, current practices on
trypanocides application for control of bovine trypanosomosis in the field in Tanzania
were studied with a view to policy advice on safe and sustainable use of trypanocides.
Methods: A cross-sectional study was conducted using a semi-structured questionnaire
administered to a total of 200 randomly selected livestock keepers in selected pastoral and
agropastoral areas within three districts namely Korogwe, Pangani and Mvomero in
eastern and north-eastern Tanzania. The data were handled using excel spreadsheet and
later exported to Epi-Info™ software program version 7 for descriptive analysis.
Results: In total, 50% of respondents in all three study districts had primary level of
education; over 40% had informal education and 5% with university education (all from
Pangani district). Most of the respondents aged 30-59 years with exception of Korogwe
district where 35% aged 20 -29 years. Over 95% of the respondents had knowledge on
tsetse as a vector of trypanosomosis and correctly identified tsetse in provided pictures.
Furthermore, 98.7% of the respondents applied pyrethroids for tsetse vector control.
Regarding parasite control practices, this study revealed significant variation in the usage
and application intervals of trypanocides. Whereas only 20% of the respondents used
chemoprophylaxis for trypanosomosis control, 69-95% wrongly used diminazene
aceturate thinking it is prophylactic while it is not. About 5-30% of the respondents used
the prophylactic drug isometamidium chloride. Most of the respondents (95% in Korogwe,
60% in Pangani and 93.1% in Mvomero) administered the drugs on their own. Improper
administration of trypanocides was significantly high in all study districts. The
respondents in Korogwe (75%) and Mvomero (72%) administered the drugs intravenously
with a view to achieve faster drug effect contrary to manufacturers’ recommendations. The
respondents (40%) in Pangani district used both intravenous and intramuscular routes.
Additionally, all respondents did not observe the recommended withdrawal periods for the
drugs.
Conclusion: This study revealed high level of trypanocides misuse that poses a high risk
of trypanosome drug resistance development as well as risks to human health from drug
residues in consumed animal products. This calls for improvement of veterinary service
delivery in pastoral and agropastoral areas of Tanzania to forestall misuse of
chemotherapeutics.
