Abstract
Although their control is based on chemical products, the infestations by ticks (Ixodes scapularis Say) are causing great losses and damages in the livestock production worldwide. In this study, the survival of the entomopathogenic nematodes Heterorhabditis bacteriophora, Steinernema carpocapsae, and Steinernema websteri in vegetal oil suspension at concentrations of 13% and 33% and their effectiveness to control ticks at concentrations of 50 ± 5 and 100 ± 10 nematodes in oil suspensions of Cymbopogon citratus, Pelargonium sp, Juniperus virginiana, Rosa sp, and Mentha piperita were evaluated in lab conditions. In field conditions, the Lethal Concentration (LC90) of S. websteri in oil suspensions of J. virginiana and C. citratus in dogs infested with ticks was evaluated. In the laboratory, it was found that an oil emulsion of C. citratus and J. virginiana at 13% maintained the survival of S. carpocapsae, H. bacteriophora, and S. websteri from 55% to 60% for a period of 96 hr. The combination of the S. websteri nematode with 50 or 100 nematodes in oil emulsions of J. virginiana at 33% presented a control effectiveness of 80–100% in adult ticks 24 hr post-application. In field, the LC90 of 119 juveniles of S. websteri in oil emulsions of J. virginiana at 33% on domestic dogs presented an accumulated and a control effectiveness of 89% after 96 hr post-application. The combined application of J. virginiana and S. websteri could be a good alternative for the control of ticks. It was observed that the time of contact and the type of vegetable oil were crucial factors to increase the effectiveness of control.
Highlights
Their control is based on chemical products, the infestations by ticks (Ixodes scapularis Say) are causing great losses and damages in the livestock production worldwide
Considering that the storage temperature of the oil emulsions was stable (23 ± 3 °C) and below 35 °C, the results suggest that the infective juveniles (IJs) of H. bacteriophora and S. carpocapsae survived because they have their own biological fitness for desiccation tolerance, especially in emulsions with C. citratus and J. virginiana, both at 13% concentration
The combined application of vegetable oil and Entomopathogenic nematodes (EPNs) could be a good alternative for the control of the ticks, as it was observed that the time of contact and the kind of oil are the determinant factors to increase control effectiveness (CE)
Summary
Their control is based on chemical products, the infestations by ticks (Ixodes scapularis Say) are causing great losses and damages in the livestock production worldwide. The lethal concentration (LC90) of S. websteri in oil suspensions of J. virginiana and C. citratus in dogs infested with ticks was evaluated. The combination of the S. websteri nematode with 50 or 100 nematodes in oil emulsions of J. virginiana at 33% presented a control effectiveness of 80 to100% in adult ticks 24 hr post-application. They can spread throughout their hosts because they hold onto them during long periods and when they finish eating they drop off the host and go to a new place This is very important for the dynamic of the illnesses they transmit and the risk of incursion of new pathogens in areas where they were absent (Díaz et al, 2012). We aimed to identify the most beneficial combination of a vegetable oil emulsion to extend the shelf-life of EPNs at room temperature and to increase their infectivity on ticks in laboratory and field evaluations
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
