[The effect of UV rays on parasitic arthropods. 3. In vitro and in vivo studies of the effect of a fractionated UV irradiation on the development stages of Psoroptes cuniculi (Acaridida: Psoroptidae)]. / Einfluss von UV-Strahlen auf parasitische Arthropoden. 3. Mitteilung: Untersuchungen in vitro und in vivo über den Einfluss einer fraktionierten UV-Bestrahlung auf Entwicklungsstadien von Psoroptes cuniculi (Acaridida: Psoroptidae).

In vitro studies were conducted into Psoroptes (Ps.) cuniculi larvae and nymphs of undefined age and gender. 30 males and females were involved in each of the experiments. Evidence was found the life expectancy of mites exposed to daily UV irradiation for 1, 2, 3, 4 or 5 minutes was reduced with significance, as compared to non-irradiated mites or to those with only one irradiation of the same length. Developmental stages of Ps. cuniculi responded in differentiated ways to the same dose rate, when applied by one single extended or fractionated shorter irradiation. Fractionated irradiation was more often survived by females than one single extended irradiation, whereas earlier death occurred to larvae following exposure to fractionated irradiation. Mange mites were not eliminated from rabbits with moderate ear mange by fractionated locally delimited in vivo irradiation, up to 16 applications of 10 minutes each or 6 or 9 applications of 10, 20 or 40 minutes each, with one-week intervals in between. Ear mange was clinically re-manifested, after irradiations had been discontinued.