Trypanocide usage and associated factors among cattle farmers in Itezhi Tezhi, Zambia
Mbewe, Joshua Njelembo
Background: The trypanocides isometamidium (ISM) and diminazene aceturate (DA) play an important role in the control of tsetse transmitted African animal trypanosomiasis (AAT) now and in the near future. The drugs are mostly administered by farmers without any veterinary supervision leading to misuse and under dosing of medication, factors that promote trypanocidal drug resistance (TDR) development. Given the devastating nature of AAT, affecting rural development, livestock and human health, the Food Agriculture Organisation (FAO) recommended guideline on trypanocide use to delay TDR development. However factors associated with trypanocide usage among farmers with regard to the FAO guidelines remain under reported in literature. Against this background a survey was undertaken to determine the factors which were associated with the predominant trypanocide usage practice among farmers with reference to the FAO guidelines in Itezhi tezhi district, central Zambia. Methodology: A questionnaire was used to collect socio-economic data and trypanocide usage practices from 90 farmers who used trypanocides in Itezhi tezhi. The animal handling facilities (AHFs) which the farmers use were stratified according to location, whether in the game management area (GMA) or non-GMA. At each AHF, blood samples from 613 randomly selected cattle were collected to determine trypanosome species prevalence, AAT status and DA resistance in Trypanosoma congolense isolates. All trypanosome positive samples upon microscopic examination of thick and thin blood smears and those with packed cell volumes (PCV) of 26% and less were subjected to polymerase chain reaction (PCR) for trypanosome isolation, identification and DA resistance testing. Results: The results showed that only 25.6% of the farmers adhered to guidelines by FAO on trypanocide use. From a total of 60 samples that were subjected to PCR 23% (14/60) were T.congolense savannah type positive, 3% (2/60) were T.vivax and 2% (1/60) had mixed infection. Seven percent (4/60) had the non-pathogenic trypanosome T.theileria and the rest of the 65% (39/60) were negative for trypanosomes. None of the 14 T. congolense isolates showed any genes associated with DA resistance. Further none of the socio-economic factors under investigation were significantly associated with trypanocide usage. However location of and AAT status at the AHF as environment factors were significantly associated with adherence to FAO guidelines on trypanocide use (P<0.05). Conclusion: DA resistance is not a problem in Itezhi tezhi despite the high levels of misuse of trypanocides suggesting a complex relationship between trypanocide usage and TDR development which requires further investigations. Additionally T.congolense accounted for the majority trypanosomal infection. Furthermore location and AAT status of the AHF were associated with adherence to FAO guidelines on trypanocide use among cattle farmers in Itezhi tezhi. We therefore recommend farmer education on DA use as well as the use of an integrated approach to control AAT especially in the GMA.
Tsetse-Flies-Control-Zambia , Wildlife diseases-Zambia