Showing papers on "Varroa sensitive hygiene published in 1993"

Facultative expression of hygienic behaviour of honey bees in relation to disease resistance

Abstract: SUMMARYFour experiments were conducted to examine factors that influence the expression of hygienic and non-hygienic behaviour in honey bees, Apis mellifera, and to examine the correlation between this behaviour and resistance to chalkbrood, Ascosphaera apis. Colonies were headed by instrumentally inseminated queens selected on the basis of uncapping and removal behaviour expressed by their progeny. In the first experiment, colony strength was altered by transferring hygienic and non- hygienic colonies from 10-frame field hives to 2-frame observation hives. This treatment significantly reduced the hygienic response of the hygienic bees but did not affect the response of the non-hygienic bees. In the second experiment, hygienic and non-hygienic bees displayed different responses to freeze-killed and live brood which had been partially or entirely uncapped. Both lines of bees recapped both partially and entirely uncapped live brood, but non-hygienic bees also recapped partially uncapped freeze-killed brood,...

Invasion of Varroa jacobsoni into honey bee brood cells: a matter of chance or choice?

Abstract: SUMMARYInvasion of Varroa jacobsoni into honey bee (Apis mellifera) brood cells was studied in three initially mite-free colonies. Frames with emerging worker brood, heavily infested with mites, were introduced into each colony and removed the next day. During the experiments ample worker brood was available for the mites to invade. Invasions into brood cells started immediately after the introduction of the mite-infested combs, showing that mites do not necessarily have to have a period on adult bees before invading a cell. However, as most mites stayed on the bees for several days or even several weeks, the average rate of invasion was rather low. In addition, replicate experiments in the three colonies showed much variation: 50% of the mites invaded brood cells within 2.0 days in the first replicate, within 8.3 days in the second replicate and within 4.3 days in the third replicate. Possible causes for the low and variable invasion rates are discussed.

Effect of brood rearing on honey consumption and the survival of worker honey bees

Abstract: SUMMARYThe cost of rearing a worker honey bee (Apis mellifera) was measured in terms of honey lost by the colony and the lifespan of the adult worker bees. Test colonies for each experiment were created by collecting bees from many different sources into a large cage and then subdividing those bees to make a group of uniform colonies. Colonies were evaluated outdoors in Baton Rouge, Louisiana, USA, during February when there was pollen but no nectar for bees to collect. Brood production did not have a significant effect on adult survival during the first cycle of brood rearing, but colonies that reared more brood during the first brood cycle had greater adult mortality during the next brood cycle. Bees used 121 g of honey to produce 1 000 cells of mixed-aged brood (eggs, larvae and pupae in a normal brood nest) and about 163 mg of honey to rear one worker bee to the pupal stage. In colonies containing brood of all stages, the weight of brood was nearly equal to (about 25% less than) the weight of honey th...

Nectar Sources for Honey Bees and the Movement of Honey Bee Colonies for Crop Pollination and Honey Production in England

Abstract: (1993). Nectar Sources for Honey Bees and the Movement of Honey Bee Colonies for Crop Pollination and Honey Production in England. Bee World: Vol. 74, No. 4, pp. 160-175.