Drop-off rhythms of engorged Rhipicephalus appendiculatus (Acarina: Ixodidae).

Journal of Parasitology (Impact Factor: 1.26). 07/1982; 68(3):484-9. DOI: 10.2307/3280962
Source: PubMed

ABSTRACT Diurnal drop-off rhythms were exhibited by all three stages of Rhipicephalus appendiculatus engorging on cattle in stalls under natural conditions of light and temperature. Most engorged larvae dropped from the host between 1000 and 1400 hours, most nymphs between 1200 and 1800 hours, and most adults between 0600 and 0800 hours. Under controlled conditions of light and temperature the drop-off rhythms of larvae and nymphs engorging on rabbits were synchronized by oscillators set in the tick in the pre- and postattachment periods. The possibility of a host-induced rhythm was inferred from the data. Drop-off patterns may be used to enhance tick control methods.

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    ABSTRACT: The pattern of drop-off of Amblyomma triguttatum triguttatum Koch was studied by infesting rabbits and rats with larvae and nymphs, and calves with adult ticks maintained at a daily photoperiodic regime of 12 h light 12 h dark. Additional information was obtained by infesting rabbits with nymphs in or out of phase with the photoperiodic regime experienced by the host.The great majority of ticks detached during the photophase: only 9.7% of larvae and 11.3% of nymphs fed on rats, 12.0% of larvae and 15.8% of nymphs fed on rabbits, respectively, and 10.0% of female ticks detached during the scotophase. The rhythm was not substantially altered by feeding nymphs in or out of phase with the photoperiodic regime of the host. The drop-off rhythm seemed to be coupled with endogenous rhythms of the host.
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