A technique for quantitative evaluation of ectoparasitic mites and insects of domestic animals.

A modified KOH dissolution technique using Tween 80 has been developed for the diagnosis and quantitative evaluation of ectoparasitic mites and insects of veterinary importance. Fifty intact skin segments from ten different domestic animals were artificially inoculated in vitro with ten specimens each of the mites Sarcoptes scabiei, Chorioptes bovis, Psoroptes ovis and Demodex caprae and insects Haematopinus eurysternus and Bovicola bovis. Sixty-seven to 88% of the mites and 80-99% of the insects were recovered by this technique. Using this method, parasitic mites and insects were found and identified in all skin scrapings from ten naturally infested animals. Using Cook's dissolution technique in our experimental design, 63.4% of C. bovis and 65% of S. scabiei mites were recovered.