The Effects of Oral and Venereal Transmission of Deformed wing virus on Honey Bee (Apis mellifera) Queen and Colony Health
Semester of Graduation
Master of Science (MS)
Honey bees are important pollinators necessary for the production of many foods. Managed honey bee colonies have been experiencing high levels of colony loss over the last decade due to a combination of different factors. Parasites, pathogens, and queen failure are repeatedly reported as major causes for colony loss, but there is little research exploring the relationship between honey bee viruses and queens. Deformed wing virus, a major honey bee virus, has a worldwide distribution, is extremely prevalent, and can infect all castes and life stages. Honey bee queens can be infected with the virus through multiple transmission routes and can be a major source of disease spread within a colony due to close contact with workers in addition to vertical transmission to the eggs she lays. It is important to understand how route of virus transmission impacts the establishment and intensity of virus infection in queens, as well as how this virus exposure could potentially impact colony strength and health. I tested this by artificially inoculating honey bee queens through oral and venereal transmission, assessing virus presence in inoculated queens over time, collecting colony assessments on colonies with inoculated queens, and running virus analysis on brood from inoculated queens. I also tested transgenerational immune priming by challenging pupae of inoculated queens with an injection of DWV-A and recording mortality, symptom development, emergence time, and virus presence and titer. I concluded that single exposure through oral and venereal transmission does not lead to an established high titer infection in queens, and that colonies with these queens are not negatively impacted as far as colony strength parameters or disease development in brood. I also found evidence that transgenerational immune priming may be occurring and expression of it differs based on genotype. Therefore I conclude that single inoculation of queens with DWV-A does not largely negatively impact honey bee queens or the colonies headed by these queens except for cases where the genotype of the queen is found to be susceptible to DWV-A which could result in queen/colony failure, and that maternal virus experience may benefit offspring challenged by the same virus.
Lang, Sarah, "The Effects of Oral and Venereal Transmission of Deformed wing virus on Honey Bee (Apis mellifera) Queen and Colony Health" (2020). LSU Master's Theses. 5096.