Nosema ceranae, Fipronil and their combination compromise honey bee reproduction via changes in male physiology

Guillaume Kairo (1) , David G. Biron (2) , Faten Ben Abdelkader (1, 3) , Marc Bonnet (1) , Sylvie Tchamitchian (1) , Marianne Cousin (1) , Claudia Dussaubat (1) , Boris Benoit (1) , Andre Kretzschmar (4) , Luc Belzunces (1) , Jean-Luc Brunet (1)

1 AE - Abeilles et Environnement
2 LMGE - Laboratoire Microorganismes : Génome et Environnement
3 Laboratoire de Zoologie et d’Apiculture
4 BioSP - Biostatistique et Processus Spatiaux

The honey bee is threatened by biological agents and pesticides that can act in combination to induce synergistic effects on its physiology and lifespan. The synergistic effects of a parasite/pesticide combination have been demonstrated on workers and queens, but no studies have been performed on drones despite their essential contribution to colony sustainability by providing semen diversity and quality. The effects of the Nosema ceranae/fipronil combination on the life traits and physiology of mature drones were examined following exposure under semi-field conditions. The results showed that the microsporidia alone induced moderate and localized effects in the midgut, whereas fipronil alone induced moderate and generalized effects. The parasite/insecticide combination drastically affected both physiology and survival, exhibiting an important and significant generalized action that could jeopardize mating success. In terms of fertility, semen was strongly impacted regardless of stressor, suggesting that drone reproductive functions are very sensitive to stress factors. These findings suggest that drone health and fertility impairment might contribute to poorly mated queens, leading to the storage of poor quality semen and poor spermathecae diversity. Thus, the queens failures observed in recent years might result from the continuous exposure of drones to multiple environmental stressors.

Mots clés: fipronil

Mots clés: Nosema ceranae; potentiel d'interaction; fertilité mâle; stress environnemental; drone

Domaines: Sciences du Vivant [q-bio]

Guillaume Kairo, David G. Biron, Faten Ben Abdelkader, Marc Bonnet, Sylvie Tchamitchian, et al.. Nosema ceranae, Fipronil and their combination compromise honey bee reproduction via changes in male physiology. Scientific Reports, 2017, 7, 14 p. ⟨10.1038/s41598-017-08380-5⟩. ⟨hal-01605612⟩