The asexual and sexual circadian rhythms of Plasmodium vinckei chabaudi, of P. berghei and of P. gallinaceum

Abstract
Plasmodium vinckei chabaudi (which has a 24 h cycle with high synchronicity) has a peak of schizogony in the early morning at about 02.00–04.00. This cycle is orientated to the cycle of the host (mouse or thamnomys). The male gametocytes become ripe for exflagellation in a well-marked wave from 22.00 to 08.00 with peak about 00.00–04.00. This timing presumably corresponds to the hours when the vector mosquitoes are most likely to suck blood, and it is adapted to facilitate transmission. The male gametocytes remain ripe for exflagellation for a mean period of about 6 h and then apparently degenerate.