THE EFFECTIVENESS OF THE DRUG FROM THE GROUP OF SYNTHETIC PYRETHROIDS AGAINST GULF COAST TICKS ON HORNED CATTLE

Abstract

The article describes the repellent and acaricidal efficacy of a drug from the group of synthetic pyrethroids against gulf coast ticks (Dermacentor marginatus) on horned cattle (70 heads of livestock). An analysis of the experimental data showed that, compared with the control group, where 100-s’ invasion of animals was observed, in the experimental group we observed a decrease in the invasion extensity (ЭИ) to 75,0% after 7 days and a significant decrease in the number of gulf coast ticks (ИО) – 3,3±0,7 specimens/head compared to control (8,5±0,6 specimens/head). At the same time, the coefficient of repelling action (КОД) was 61,2%. After 14 days, the invasiveness in the experimental group was 80,0%, the parasitic index (ИО) has made 4,3±0,8 specimens/head, and the coefficient of repelling action (КОД) was 41,9%. After 21 days of the experiment, the coefficient of the repelling action (КОД) continues to decline to 29,9%. The invasion extensity rises to 85% after 21 days and to 91% after 28 days. The parasitic index (ИО) also continues to increase: 5,4±0,8 specimens/head and 6,6±0,8 specimens/head. One hundred percent effect of the drug in the experimental group was observed in 25% of animals after 7 days, after 14 days it was observed in 20%, after 21 days it was in 15%, and after 28 days in 10% of animals. Thus, the use of the drug from the group of synthetic pyrethroids (active substance is D-2, 10 mg/1 ml) at a dose of 0,3 ml per 10 kg of weight did not give a 100-s’ acaricidal effect against gulf coast ticks of the Dermacentor marginatus genus. The coefficient of repelling action (КОД) throughout the all experiment was in the range of 29,9-61,2%, which is lower than the recommended 70%.