Veterinary Medicine and Biotechnology

Abstract

The effect of flumethrin on unfed adult Rhipicephalus evertsi collected from the Sokoine University Cattle Farm was determined, using filter paper discs  impregnated  with 31.25 ppm and I5.625 ppm (active ingredient = a.i) of the pyrethroid. The pesticide was further tested in the field, using the pour-on technique at a dose of 10ml of flumethrin (1% a.i) per 100 kilogrammes body weight of the animals. The laboratory tests revealed 100% mortality of ticks after 24hours exposure to both concentrations of acaricide. The exposure time required for killing 50% of the ticks (LT₅₀) was less than lh. 1n the field trials, all engorged female ticks were cleared within 24h following initial treatment and no more engorgement occurred during the trial period of 49 days. Total clearance of immature and unfed adult occurred after the third treatment which was done on day 28. Overall efficacy of flumethrin pour-on was 97.28%. Limited mortalities of the ticks were also observed in the control group and such mortalities were attributed to contact rub-off effect as both treated and control animals grazed together. It was concluded that flumethrin pour-on was effective against all stages of multi-host ticks in the area and probably elsewhere in Tanzania