Field assessment of the efficacy of Tephrosia Vogelii(hook)plant leaf extracts for control of ticks on naturally infested Cattle in Njola Veterinary Camp of Monze District,Zambia

Abstract

Ticks and tick borne diseases (TBDs) are responsible for substantial direct and indirect economic losses in livestock production in the sub-Saharan countries. Conventional acaricide methods for controlling ticks and TBDs have not been very effective among small scale livestock farmers largely due to the high cost of acaricides and lack of adequate extension and outreach services provided to them. Failure to follow instructions and adherence in preparation of the right dilutions of acaricides has been considered to be responsible for development of tick resistance to most acaricides in use which resulted in increase of TBDs out breaks. This occurrence has prompted livestock farmers and researchers to seek none conventional alternative and sustainable tick control methods. None conventional method should be readily available, simple in processing, cheap, and preferably not harmful to the environment. We identified T.vogelii a tropical leguminous herbal plant with natural pesticide and acaricidal properties, as such a bio-acaricide candidate.Tephrosia is a short lived, slow growing, herbaceous, frost susceptible perennial plant and has soft hairy velvet leaves which are pleasant to touch. A baseline survey was done using a questionnaire to find out the levels of indigenous knowledge existing for tick control management. The results indicated that 51 percent of the respondents knew that ticks transmit diseases to cattle and 41 percent revealed the use of cow dung as a method to kill ticks. Cattle used were selected for field experiments from small scale farmers’ herds with no or, poor record of tick control in Monze district. Six groups of five (5) each were allotted into six (6) treatment groups of5, 10, 20, 40 percent w/v whilea negative control group of five (5) animals were also sprayed with ordinary water. A positive control group of five (5) animals were sprayed with a commercial acaricide (Amitraz®) at recommended dosage of 1:500 dilution by the manufacturer (Ecomed limited company of south Africa). All treatment groups were sprayed with same quantities in volume of the different preparations. Tick counts were conducted on each animal before and after treatments. The results showed that, the efficacy of the botanical extracts was sustained up to six days post treatment.There was reduction in tick counts at all concentration levels used in groups. It was however observed that 0.05 percent w/v concentration level of T.vogelii plant leaf extracts had the highest reduction on tick counts of up to 88 percent within 48 hours post treatment. The 0.1percent w/v had 71 percent reduction, 0.2 percent w/v had 74 percent, and lastly 0.4percentw/v had 80 percent reduction The observed tick reductions were found to be statistically significant at all treatment levels (p-value < 0.001). The protection period against reinfection is in excess of six days. The use of T. vogelii as bioacaricide proved effective against ticks at very low concentrations of only 5 percent w/v leaf extract. The extract is cheaper to use by small scale livestock farmers where they cannot afford to use chemical acaricides