Beekeeping: Science updates

  Science updates: Summary of the Study on Monocrotaline's Effects on Honey bees     The study investigates the biological damage caused by monocrotaline (MCT), a toxic alkaloid found in Crotalaria plants, on the brain and intestinal tissues of honey bees ( Apis mellifera ). The research highlights the potential risks MCT poses to pollinators, particularly in relation to their cognitive and physiological functions. MCT exposure led to a significant reduction in head weight and swelling of the abdomen in honeybees. Histological analysis revealed damage to the brain's Kenyon cells, which are crucial for cognitive functions, and thinning of the midgut wall.   The study found increased levels of reactive oxygen species (ROS) and decreased antioxidant enzyme activity in the brains of MCT-exposed honey bees, indicating oxidative stress. Conversely, the midgut showed increased antioxidant capacity despite structural damage. Apoptosis rates were elevated in ...

  Science updates: Summary of Research on Varroa Destructor Resistance in Honey Bees The study investigates the transmission of Varroa destructor resistance traits in honey bees, focusing on whether these traits are learned by worker bees or encoded in the queen's genetics. Varroa is a significant pest for beekeepers globally, and understanding how resistance is passed on is crucial for effective bee management without reliance on miticides. The research involved re-queening mite-resistant colonies with susceptible queens in Hawaii and the UK, and vice versa, to observe the effects on mite levels over time. The study measured mite infestation levels, recapping rates, and the ability to remove mite-infested cells.   The results indicated that resistant traits are primarily encoded in the queen rather than learned by worker bees. Colonies led by susceptible queens showed significantly higher mite levels compared to those led by resistant queens, regardless of ...

  Science updates: Winter mortality & temperature variations and Varroa mites   The study examines the causal relationship between honey bee (Apis mellifera) winter mortality and environmental factors such as temperature variations and Varroa mite density. The research, conducted in a Central European apiary from 1991 to 2023, reveals consistent mortality patterns across years, with four distinct clusters of year-specific mortality trajectories identified. However, no significant differences were found in seasonal temperatures or Varroa destructor density among these clusters .   The study employs generalized additive mixed models (GAMM) to analyze individual bee mortality rates and structural equation models (SEM) to explore the causal network linking environmental conditions to bee mortality and honey production.   The results indicate that increased winter mortality is associated with lower winter temperatures and higher autumn infestations of ...