BIOLOGY OF IXODES (PHOLEOIXODES) HEXAGONUS UNDER LABORATORY CONDITIONS .1. IMMATURE STAGES

A rearing method for Ixodes (Pholeoixodes) hexagonus, the hedgehog tic k, was established which enabled the life cycle of immature stages to be studied under laboratory conditions. Larvae were fed on Swiss mice and nymphs on the ears of New Zealand rabbits. The feeding time of the larvae and nymphs on both hosts was 4-17 days. Larvae moulted to nymp hs 15-21 days after detachment from mice. The premoulting period was 1 3-26 days for newly emerged males and 15-27 days for females. Engorged nymphs which developed into males weighed less (5.64 +/- .9 1 mg) tha n those that developed into females (6.019 +/- 88 mg). The sex ratio ( male: female) under laboratory conditions was 1:1.13.