@article{SteijvenSpaetheSteffanDewenteretal.2017, author = {Steijven, Karin and Spaethe, Johannes and Steffan-Dewenter, Ingolf and H{\"a}rtel, Stephan}, title = {Learning performance and brain structure of artificially-reared honey bees fed with different quantities of food}, series = {PeerJ}, volume = {5}, journal = {PeerJ}, number = {e3858}, doi = {10.7717/peerj.3858}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170137}, year = {2017}, abstract = {Background Artificial rearing of honey bee larvae is an established method which enables to fully standardize the rearing environment and to manipulate the supplied diet to the brood. However, there are no studies which compare learning performance or neuroanatomic differences of artificially-reared (in-lab) bees in comparison with their in-hive reared counterparts. Methods Here we tested how different quantities of food during larval development affect body size, brain morphology and learning ability of adult honey bees. We used in-lab rearing to be able to manipulate the total quantity of food consumed during larval development. After hatching, a subset of the bees was taken for which we made 3D reconstructions of the brains using confocal laser-scanning microscopy. Learning ability and memory formation of the remaining bees was tested in a differential olfactory conditioning experiment. Finally, we evaluated how bees reared with different quantities of artificial diet compared to in-hive reared bees. Results Thorax and head size of in-lab reared honey bees, when fed the standard diet of 160 µl or less, were slightly smaller than hive bees. The brain structure analyses showed that artificially reared bees had smaller mushroom body (MB) lateral calyces than their in-hive counterparts, independently of the quantity of food they received. However, they showed the same total brain size and the same associative learning ability as in-hive reared bees. In terms of mid-term memory, but not early long-term memory, they performed even better than the in-hive control. Discussion We have demonstrated that bees that are reared artificially (according to the Aupinel protocol) and kept in lab-conditions perform the same or even better than their in-hive sisters in an olfactory conditioning experiment even though their lateral calyces were consistently smaller at emergence. The applied combination of experimental manipulation during the larval phase plus subsequent behavioral and neuro-anatomic analyses is a powerful tool for basic and applied honey bee research.}, language = {en} } @article{SchilcherHilsmannAnkenbrandetal.2022, author = {Schilcher, Felix and Hilsmann, Lioba and Ankenbrand, Markus J. and Krischke, Markus and Mueller, Martin J. and Steffan-Dewenter, Ingolf and Scheiner, Ricarda}, title = {Honeybees are buffered against undernourishment during larval stages}, series = {Frontiers in Insect Science}, volume = {2}, journal = {Frontiers in Insect Science}, issn = {2673-8600}, doi = {10.3389/finsc.2022.951317}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-304646}, year = {2022}, abstract = {The negative impact of juvenile undernourishment on adult behavior has been well reported for vertebrates, but relatively little is known about invertebrates. In honeybees, nutrition has long been known to affect task performance and timing of behavioral transitions. Whether and how a dietary restriction during larval development affects the task performance of adult honeybees is largely unknown. We raised honeybees in-vitro, varying the amount of a standardized diet (150 µl, 160 µl, 180 µl in total). Emerging adults were marked and inserted into established colonies. Behavioral performance of nurse bees and foragers was investigated and physiological factors known to be involved in the regulation of social organization were quantified. Surprisingly, adult honeybees raised under different feeding regimes did not differ in any of the behaviors observed. No differences were observed in physiological parameters apart from weight. Honeybees were lighter when undernourished (150 µl), while they were heavier under the overfed treatment (180 µl) compared to the control group raised under a normal diet (160 µl). These data suggest that dietary restrictions during larval development do not affect task performance or physiology in this social insect despite producing clear effects on adult weight. We speculate that possible effects of larval undernourishment might be compensated during the early period of adult life.}, language = {en} }