Requeen with hygienic stock

Replace the existing queen with a new queen from hygienic breeding stock to break the sacbrood cycle and strengthen the colony's ability to detect and remove infected larvae. This is especially effective for colonies with recurring or persistent sacbrood infections.

Why It Works

Sacbrood virus (SBV) susceptibility has a genetic component. Queens bred from hygienic lines produce workers that detect and remove diseased brood within 24-48 hours, limiting viral spread through the colony. A new queen also provides a brood break during introduction, which temporarily halts the virus's reproduction cycle in larval cells.

Tips

• Source queens from breeders who test for hygienic behavior (freeze-kill assay with 95%+ removal rate)
• Remove the old queen 24 hours before introducing the new one in a candy-plug cage
• Allow 3-5 days for colony acceptance before releasing the new queen
• Time requeening during a nectar flow or provide supplemental feeding to reduce stress during the transition
• Combine with frame removal of heavily affected brood to accelerate recovery