Progress 09/01/20 to 08/31/22
Outputs
Target Audience:The target audience reached by our efforts during the entiretyreporting period included beekeeping groups, graduate students, and scientists. I presented research from the NIFA fellowship to numerous conferences; American Bee Research, USDA seminar series, and the North American Pollinator Protection Campaign, and the American HoneyProducers conference. I spoke about my NIFA research and had an open discussion with a California Beekeeping Group to identify overlapping areas of interest. Furthermore, I hosted a workshop for USDA grad students and technicians for coding and statistical analysis. Changes/Problems:We decided to look at the neurobiological effects from a different angle considering preliminary data we and our collaborators collected. For example, we had colonieseating the fatty acid enriched pollen patties for 5 weeks, and we measured how these diets impact their hygienic ability. Our data were inconclusive because of the wide range of variations of the high hygenic phenotype. We usedfreeze-kill brood assays for hygienic assays which could be a limitation because dead brood are not parasitized brood so olfactory cues may differ.Our collaborator Sharoni Shafir on the NIFA fellowship collected electroanntenogram recordings to determine if fatty acids affect detection and antennal lobe activity; these resultsfound this was not the case. Considering these findings we decided to focus on measuringneurobiological mobilization effects of fatty acids on hygienic lines.To better understand the underlyingfatty acid effects on neurobiology andhygienic behavior, we analyzed fatty acid storage and mobilization in brains using GCMS onhoney bees from high hygenic lines and unselected lines. We found significant differences in fatty acid mobilization in brains of bees fed unbalanced versus balanced diets. Interestingly our data showed neurobiological differences in fatty acid profiles in bees fed these diets. These data are currently in the process of co-author review in a manuscript. What opportunities for training and professional development has the project provided?The fellowship enabled Dr. Meg Bennett to build relationships within the ARS. She is now the Pacific West Area ARS postdoc representative, and she serves as the chair of the Mentoring Committee. Meg gave a presentation on the NIFA fellowship research at two ARS seminars; ARS Brown Bag Seminar Series, and the ARS-Alumni Series (Fargo). She has monthly meetings with the CHBRC Research Leader to recieve mentoring on how to be in leadership. Meg has also learned advanced techiniques such as GC-MS analysis, BCA protein analysis, Vanillian lipid analysis and hygienic testing.These skills will bevaluable as Meg aspires to be a research scientist with the ARS. How have the results been disseminated to communities of interest?Meg presented research at the American Bee Research, USDA seminar series, the North American Pollinator Protection Campaign, and The American Honey Bee Producers Association.We conducted and analyzed experiments and shared results with multiple Bee keeper groups mentioned in the Target Audience section.Meg hosted a statistical analysis workshop for graduate students and technicians at the CHRBC. We hosted a Q&A and research dissemination with beekeepers. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
California almonds are a $6 billion dollar industry, and honey bee pollination services are vital to this scale of production. Since the appearance of colony collapse disorder in honey bees in 2005, costs of almond production have increased $112 per acre annually. The leading colony stressor is the Varroa mite, which weakens colonies to pesticides and other sources of stress, ultimately leading to colony collapse. Miticides are ineffective, but are currently the main method of controlling mites. Honey bees have evolved strategies to control parasites called hygienic behavior. This involves locating and removing diseased or parasitized brood, helping honey bees prevent disease from spreading through the colony or an agricultural setting. Sense of smell (olfaction) plays a critical role in hygienic behavior, as hygienic bees are more sensitive to olfactory cues from diseased brood. As with many behaviors, hygienic behavior has a genetic component but it is unclear how the environment - such as nutrition - influences the trait. We discovered diets high in omega-6 impaired bee ability to learn diseased brood odors. This is a problem because almond pollen is high in omega-6. Although, our data show if bees were supplemented with high omega-3, then they could successfully learn diseased brood odors. Thus, increased levels of properly balanced dietary fatty acid diets improve olfaction, and could have downstream effects on hygienic behavior and neurobiolgoy. Understanding whether nutrition can amplify this phenotype may lead to less miticide use for controlling Varroa mites, but also alleviating parasitic stress can strengthen colony resistance to pesticides used in agriculture. The accomplishments under objective 1 are as follows; 1) A successfuly published manuscript describing the effects of fatty acids on cognition and fatty acid mobilization.Under the second objectives our accomplishments include; 2) running GC-MS on tissues of bees fed fatty acid diets from hygienic lines of honey bees.Below we describe in more detail the data collected and key outcomes. Experiments 1: The role that lipids play in the physiology and behavior of adult bees is gaining attention. For example, recent research suggests that fatty acids impact olfactory learning in honey bees. Olfaction is crucial to performing brood care and cell cleaning behaviors by nurse bees. Thus, we targeted the early adult, pollen feeding stage to examine how fatty acids affect cognition. We fed young workers (days 0-9) diets balanced or unbalanced in their ratio of essential fatty acids (ω-6:3) sourced from pollen and cooking oils. We then measured their ability to learn healthy and damaged brood odors, as well as their ability to discriminate between the two. Workers fed balanced diets could significantly learn and discriminate between brood odors better than workers fed unbalanced diets. Consumption of both diet types decreased with age, but the cognitive effects of diets remained. These results reveal crucial insight about how diet affects young worker cognitive development, which could have down-stream effects on disease control in the colony. We sampled bees before the experiment to get base line numbers of fatty acids coming in from natural pollen. They are eating the fatty acid enriched pollen patties for 5 weeks, and we measured how these diets impact their hygienic ability. Our data were inconclusive because of the wide range of variations of the high hygenic phenotype. We usedfreeze-kill brood assays for hygienic assays which could be a limitation because dead brood are not parasitized brood so olfactory cues may differ.Our collaborator Sharoni Shafir on the NIFA fellowship collected electro anntenogram recordings to determine if fatty acids affect detection and found this was not the case. Considering these findings we decided to focus on testing neurobiological effects of fatty acids on hygienic lines. Experiment 2: Honey bees continue their development even after emergence, thus the first week of life can influence morphology and physiology in later ages. We now know that FA diets affect discriminatory ability to both floral and brood odors, suggesting these diets may affect cognition more generally. To better understand the underlyingfatty acid effects on neurobiology andhygienic behavior, we analyzed fatty acid storage and mobilization in brains of honey bees from high hygenic lines and unselected lines.Dr. Meg Bennett, published Experiment 1, fatty acids and cognition,in the Journal of Experimental Biology (Bennett et al. 2022). Through collecting these data, she learned GC-MS techniques in order to analyze pollens and tissues for lipids. The manuscript for Experiment 2 is currently under review by co-authors and is close to being submitted.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2022
Citation:
Meghan M. Bennett, Ashley C. Welchert, Mark Carroll, Sharoni Shafir, Brian H. Smith, Vanessa Corby-Harris, Unbalanced fatty acid diets impair discrimination ability of honey bee workers to damaged and healthy brood odors
Journal of Experimental Biology � Mar 3, 2022
|
Progress 09/01/20 to 08/31/21
Outputs
Target Audience:The target audience reached by our efforts during this reporting period includedbeekeeping groups and grad students. I presented research from the NIFA fellowship to numerous conferences; American Bee Research, USDA seminar series, and the North American Pollinator Protection Campaign. I spoke about my NIFA research and had an open discussion with a California Beekeeping Group. Furthermore, I hosted a workshop forUSDA grad students and technicians for coding and statistical analysis. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?The fellowship enabled Dr. Meg Bennett to build relationships within the ARS. She is now the Pacific West Area ARS post-doc representative, and she serves as the chair of the Mentoring Committee. Meg gave a presentation on the NIFA fellowship research at two ARS seminars; ARS Brown Bag Seminar Series, and the ARS-Alumni Series (Fargo). She has monthly meetings with the CHBRC Research Leader to recieve mentoring on how to be in leadership. This has been valuable as Meg aspires to be a Research Leader, in addition to running her own lab. How have the results been disseminated to communities of interest?Meg has disseminated this research through seminars and workshops. She had a conversation with a California Beekeeping group about her research and future directions. Meg made her email available to beekeepers to continue conversations about research.She hosted a "Coding in R" workshop to CHBRC grad students and technicians.Furthermore, she gave two 45 minute ARS seminars to fellow scientists on her NIFA research. What do you plan to do during the next reporting period to accomplish the goals?We made very significant progress on data collection in FY 2021, thus our efforts are mostly focused on finishing those experiments and analyzing data. We are currently working up the GC-MS data and are finishing this before the end of 2021. We plan to complete the electrophysiological and histological experiments by January 2022. We will replicate our hygienic experiments next field season, Spring 2022.
Impacts
What was accomplished under these goals?
California almonds are a $6 billion dollar industry, and honey bee pollination servicesare vital to this scale of production. Since the appearance of colony collapse disorder in honey bees in 2005, costs of almond production have increased $112 per acre annually. The leading colony stressor is the Varroa mite, which weakens colonies to pesticides and other sources of stress, ultimately leading to colony collapse. Miticides are ineffective, but are currently the main method of controlling mites. Honey bees have evolved strategies to control parasites called hygienic behavior. This involves locating and removing diseased or parasitized brood, helping honey bees prevent disease from spreading through the colony or an agricultural setting. Sense of smell (olfaction)plays a critical role in hygienic behavior, as hygienic bees are more sensitive to olfactory cues from diseased brood.As with many behaviors, hygienic behavior has a genetic component but it is unclear how the environment - such as nutrition - influences the trait. We discovered diets high in omega-6 impaired bee ability to learn diseased brood odors. This is a problem because almond pollen is high in omega-6. Although, our data show if bees were supplemented with high omega-3, then they could successfully learn diseased brood odors. Thus, increased levels of properly balanced dietary fatty acid diets improve olfaction, andcould have downstream effects on hygienic behavior. Understanding whether nutrition can amplify this phenotype may lead to less miticide use for controlling Varroa mites, but also alleviatingparasitic stress canstrengthen colony resistance to pesticides used in agriculture. The accomplishments under objective 1 are as follows; 1) we started electrophysiological measurements of hygienic bees, 2) currently histologically staining brains of bees fed fatty acid diets. Under the secondobjectivesour accomplishments include; 1) collecting behavioral data on bees fed fatty acid diets, 2) running GC-MS on tissues of bees fed fatty acid diets, 3) currently testing diets at the hive level and measuring hygienic behavior. We submitted a manuscript for internal review at the ARS-533 for the behavioral and GC-MS data, thus we are very close to a peer-reviewed publication of some the behavioral and physiological work of the NIFA fellowship. Below we describe in more detail the data collected and key outcomes. Experiments 1: The role that lipids play in the physiology and behavior of adult bees is gaining attention. For example, recent research suggests that fatty acids impact olfactory learning in honey bees. Olfaction is crucial to performing brood care and cell cleaning behaviors by nurse bees. Thus, we targeted the early adult, pollen feeding stage to examine how fatty acids affect cognition. We fed young workers (days 0-9) diets balanced or unbalanced in their ratio of essential fatty acids (ω-6:3) sourced from pollen and cooking oils. We then measured their ability to learn healthy and damaged brood odors, as well as their ability to discriminate between the two. Workers fed balanced diets could significantly learn and discriminate between brood odors better than workers fed unbalanced diets. Consumption of both diet types decreased with age, but the cognitive effects of diets remained. These results reveal crucial insight about how diet affects young worker cognitive development, which could have down-stream effects on disease controlin the colony. Currently, we are testing these diets at the hive level, and measuring effects of hygienic behavior. We have colonies that we measured exhibiting "high" and "low" hygienic ability and are feeding them fatty acid diets. We are sampling bees before the experiment to get base line numbers of fatty acids coming in from natural pollen. They are eating the fatty acid enriched pollen patties for 5 weeks, and we will measure how these diets impact their hygienic ability. Experiments 2:Honey bees continue their development even after emergence, thus the first week of life can influence morphology and physiology in later ages. We now know that FA diets affect discriminatory ability to both floral and brood odors, suggesting these diets may affect cognition more generally. To better understand the underlying neural mechanisms of fatty acids on cognition and hygienic behavior, we currently working up data from multiple experiments. First, we are analyzing brain GC-MS data to understand how fatty acids are being stored in the brain. Second, we are in process of histologically staining brains of bees fed fatty acid diets for energy usage. Third, we are in process collecting electrophysiological measurements of the brain from hygienic bees. Fourth, we are processing brains for lipid content in genetic lines of honey bees fed fatty acid diets. Dr. Meg Bennett, the post-doc, submitted a manuscript from this research (Experiments 1) for ARS internal review, thus it is very close to publication. Through collecting these data, she learned GC-MS techniques in order to analyze pollens and tissues for lipids. Also, she learned how to measure hygienic behaviors within a colony, a techniques the CHBRC does not regularly employ.
Publications
|