Science updates: Honey bees & effects of nutrition & queen age

 

Science updates:

Honey bees & effects of nutrition & queen age

 

The study investigates the impact of nutrition and queen age on the health and performance of honey bee colonies overwintering in a southern climate. The research, which spanned from July to January in the Imperial Valley of California, involved 252 commercial colonies across three apiary sites. The colonies were divided into groups with either young or old queens and were fed either artificial diet or a mixture of artificial diet and natural pollen.

 

Key findings include:

1.     Colonies with young queens produced significantly more brood than those with old queens, with a 24-25% increase in brood production in November and January.

2.     Supplemental feeding with natural pollen led to a non-significant increase in brood production compared to artificial feed alone.

3.     The expression of vitellogenin (vg) and its homologs (vg-like-A, -B, and -C) varied seasonally and was influenced by queen age and diet, with vg-like-A showing a potential role in winter bee phenotypes.

4.     Immune-related gene expression generally increased or remained stable over the winter months, suggesting a continuous energy investment in immune function.

5.     Apiary site had a significant effect on total brood production and pollen storage, with site 2 outperforming the others in brood production and pollen accumulation.

6.     Pathogen levels varied over time, with Varroa levels decreasing after acaricide treatment and deformed wing virus levels peaking in January.

7.     Molecular correlations indicated that vg expression was strongly correlated with vg-like-A and that immune gene expression was correlated with each other and with pathogen levels at different time points.

 

The study concludes that young queens and supplemental feeding with natural pollen may improve colony brood rearing and overwintering survival. It also highlights the importance of landscape variation and suggests that colony-level molecular biomarkers, such as vg and vg-like genes, could be useful in assessing honey bee health and informing management decisions. The research provides insights into the dynamics of managed colony performance and the potential benefits of incorporating natural pollen into supplemental feeding regimes.

 

Reference:

Ricigliano, V. A., Mott, B. M., Floyd, A. S., Copeland, D. C., Carroll, M. J., & Anderson, K. E. (2018). Honey bees overwintering in a southern climate: longitudinal effects of nutrition and queen age on colony-level molecular physiology and performance. Scientific Reports, 8(1), 10475.

                                    ******////////////**********