Effect of Queenlessness on Worker Survival, Honey Gain and Defence Behaviour in Honeybees
SummaryThe effects of queenlessness on worker honeybees (Apis mellifera?) were tested with 50 colonies in groups of 10 (five treatments and two replicates) in August, October and December, 1984 and February and April, 1985 in Baton Rouge, Louisiana. The 10 colonies in each group were all from a single heterogeneous mixture of bees, and each colony began with about 6000 workers and no brood. The five treatments each lasted for 28 days and consisted of (1) caged queen for 28 days, queenless for 0 days; (2) caged queen for 21 days, queenless for 7 days; (3) caged queen for 14 days, queenless for 14 days; (4) caged queen for 7 days, queenless for 21 days and (5) caged queen for 9 days, laying queen for 19 days (control). With prolonged queenlessness worker survival, colony weight gain and defence behaviour (number of stings) decreased. Queenlessness did not induce drifting.
Early Death of Newly Emerged Worker Honeybees in Laboratory Test Cages
SummaryNewly emerged worker progeny of certain queens exhibited an early period of death after being put into laboratory test cages. Examination of early death in the progeny of 82 queens demonstrated that: it occurred during days 1–8 in the cage; 0–22% of the cage population died during this period; among progeny of the median queen, an average of 2–0% of the bees died; there were significant differences in the incidence of early death among the progeny of different queens (P<0·001); the incidence of early death appeared to be repeatable. Early death in the cage could be virtually eliminated by providing young laying queens.
Target of inhibition by the anti-lipogenic antibiotic cerulenin of sterol synthesis in yeast.
Abstract The antibiotic cerulenin inhibited the incorporation of 14 C-acetyl-CoA by 67% at a concentration of 9 × 10 −6 M but not that of 14 C-HMG-CoA into the non-saponifiable fraction in a cell-free extract of Saccharomyces cerevisiae . Cerulenin markedly inhibited the activity of partially purified HMG-CoA synthase. No inhibition of acetoacetyl-CoA thiolase activity was observed in the same preparation of HMG-CoA synthase. Therefore, cerulenin inhibition of overall sterol synthesis may be accounted for by the specific inhibition of HMG-CoA synthase activity.