Evaluation of Ectopar for the control of the poultry red mite Dermanyssus gallinae

Abstract: The poultry red mite, Dermanyssus gallinae, is a common problem in poultry facilities, causing great discomfort for the hens and effecting the production economically. Few efficient acaricides are available and there is a need for new control methods since resistance has become a problem in some cases. The aim of this study was to evaluate the efficiency of the new liquid silica control agent Ectopar, on the poultry red mite. An initial in vitro test of Ectopar and its two components individually was performed, where live mites were sealed in together with filter paper impregnated with one of the three solutions prepared. The survival of the mites was thereafter recorded repeatedly during a period of 120 hours and compared to a control. For the field study, two poultry farms with different housing systems were used, one with furnished cages (farm 1) and one with a single tier floor system (farm 2). Plastic cardboard traps were placed out where mites were known to cluster in both farms for weekly monitoring of the mite infestation level. The traps were collected every 7th day and replaced with new ones. The number of mites in each trap were counted and recorded in a laboratory. When the mites over time had doubled in number, ensuring a population growth prior to treatment, Ectopar was administrated in the two farms respectively. Monitoring of mite numbers continued for the following 6 weeks on farm 1 and 5 weeks on farm 2. The results from the in vitro test showed no differences between treatments and the control, indicating no controlling effect of Ectopar on the poultry red mite. In the field study, Ectopar treatment merely accomplished a reducing effect of up to 37 % on farm 1 which were nonsignificant (NS). On farm 2, initially the reduction reached a maximum of 24 % and was also NS. After the manure trays on this farm had been removed, however, there was a significant reduction obtained of 86 %, compared to before treatment. This was because a major site of mite aggregation was removed and therefore this reduction cannot be assigned Ectopar. In conclusion, Ectopar alone is not an effective control agent against D. gallinae under the presumptions of this study.