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The role of the queen in wax secretion and comb building in the Cape honeybee, Aps mellifera capensis (Escholtz)Whiffler, Lynne Anne January 1992 (has links)
The role of the queen in wax secretion and comb building was studied in the the Cape honeybee, Apis mellifera capensis (Escholtz). The percentage of bees bearing wax and the amount of wax borne by these bees did not differ between the experiments. This meant that the queenless and queenright colonies had the potential to construct equal amounts of comb as the amounts of wax available for comb building was the same. Contrary to this prediction, queenright colonies constructed 8 times more comb than their queenless counterparts. Queenright Apis mellifera scutellata colonies constructed 4 times more comb than their queenless counterparts. The increased amount of 9-oxo-2-decanoic acid (90DA) in the A.m.capensis mandibular gland secretions could not alone account for this difference. In fact, A.m.capensis and A.m.scutellata colonies constructed similar amounts of comb when they were given their own queens or queens from the other race. Worker bees need to have direct contact with their queen for comb building to be enhanced. Even when the queen had her mandibular glands extirpated and tergite glands occluded large amounts of comb were constructed than when access to the queen was limited. Direct access to the head of a mated queen proved to be the stimulus enhancing comb building. No comb was constructed when the workers had access to the abdomen of the queen. Virgin queens did not stimulate comb building. The relatively large amounts of 90DA and 9HDA from the mandibular glands of Cape virgin queens had not influenced comb building. Worker sized cells were generally constructed. These cells were slightly smaller than those constructed by European honeybees, but were indicative of African bees. A few queen less colonies constructed cells that were of an intermediate drone and worker size. Four mandibular gland pneromones were measured by gas chromatography. No correlations between these pheromones and the comb construction measurements were found. It is unlikely that the mandibular gland pheromones are the only pheromones that stimulate comb building. Pheromones from other glands on the head may contribute towards the enhancement of comb building, and they are not present in virgin queens
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Physico-chemical characteristics of waxes produced by the African honeybee, apis mellifera scutellata.Kurstjens, Sef Paul. January 1990 (has links)
A thesis submitted to the Faculty of Science, University of the
Witwatersrand, Johannesburg, in fulfilment of the requirements
for the degree of Doctor of Philosophy / In this dissertation the physical and chemical alterations induced by
mastication and manipulation of wax by the worker bee in honeycomb
construction, and the subsequent contribution afforded the structural integrity
of the nest, are elucidated.
In comb building, the freshly secreted wax scales are mandibulated together
with a frothy salivary emulsion, and added piece-meal to form honeycomb.
Textural modifications were revealed using X-ray crystallography. While virgin
scale wax is highly structured, with the crystallites aligned approximately
perpendicular to the planar surface, comb wax has a random crystallographic
arrangement. This reflects a disruption of the crystallite structure following the
mechanical insult of mastication. Chemical analyses included investigation of
both lipid and proteinaceous elements. Lipid composition was evaluated by
enzyme-catalyzed as well as thin-layer and gas-liquid chromatographic
methods. The results indicate a reduction in scale diacylglycerols with a
corresponding increase in comb saturated monoaeylglycerols. Such
modifications are highly suggestive of lipase activity within the salivary
addition. The proteins of comb and scale wax were analyzed
electrophoretically, under reduced conditions. Each wax possesses unique
polypeptide fractions, in addition to sharing common protein species, It is
speculated that those in common represent integral proteins, such as transport
molecules, while the disparities noted may be due to salivary enzymatic
degradation, or even glycosylation.
The effects of these textural and chemical alterations on the mechanical
behaviour of the waxes was assessed. Tensile tests were performed on a
variety of scale and comb wax preparations over the range of temperatures
likely to impinge on the honeybee nest. These investigations reveal the specific
structural contributions made by each of the physico-chemical alterations
described. Further, they demonstrate that while scales are ideal moulding
materials due to their high distensibility and low stiffness, the greater
resistance to deformation and lower potential for extension makes comb wax
a superior structural material. The mechanical advantage for including
propolis and cocoon silk within the comb structure was also investigated.
Tensile testing indicates that the resultant composite material is structurally
superior, largely due to the presence of silk reinforcement. / Andrew Chakane 2018
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Effects of used brood comb and propolis on honey bees (Apis mellifera L.) and their associated bacterium, Melissococcus plutoniusMurray, Stephanie K. January 2019 (has links)
No description available.
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