Organically managed honey bees have healthier gene activity than conventional honey bees

Honey bee health is affected by a myriad of factors including the diversity and quality of food available to them, exposure to pesticides, and attacks by parasites and diseases. Genetic activity linked to immune response can be measured to indicate health of the hive. A new study published in the journal Insects found that genetics of honeybees that are organically managed indicate less environmental stress and higher immunity than bees from conventional hives. Organic management of honey bees prohibits the use of chemical pesticides in hives, and bees must have access to organically certified agricultural land to forage. In contrast, conventionally managed honey bees are often fed corn syrup or sugar syrup, and placed in conventional monoculture cropping systems to forage, where pesticides are frequently used. Antibiotics, pesticides, and sometimes synthetic waxes are used in conventionally managed hives. Malnutrition and chemical exposure can also trigger a genetic response that indicates lower immunity. This study aimed to compare genetic activity in organic to conventional honey bees as an indication of their overall health and potential to withstand exposure to a devastating parasitic mite, Varroa destructor. Without exposure to varroa, conventional honey bees had higher levels of immune response genes than organic, suggesting that conventional bees were stressed by other environmental factors like pesticide exposure, poor diets or disease. Organic honeybees without exposure to varroa also had the highest levels of genes that indicate good foraging capacity, suggesting greater overall health. Once exposed to varroa, honey bees under both management strategies had higher gene expression indicating an immune response.  However, the healthier baseline of organic bees suggests they have an upper hand in withstanding varroa infestation. This study shows chemical stressors and poor diets of conventionally managed honey bees compromise the hive’s overall health, while organic management can reduces exposure to critical environmental stressors, making them healthier at the start.

 

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