What is Open Brood?

During an inspection, open brood is one of the best indicators of the queen's recent activity. Observing eggs and larvae at different stages confirms that laying has occurred in the past few days and that worker bees continue to feed the brood normally.

After laying an egg, the queen begins a process that will culminate, days later, in the birth of a new bee. While the cell remains open, it is possible to first observe the egg and then the growing larva. This combination constitutes open brood.

Eggs typically remain in this stage for about three days. After hatching, a small white larva emerges, continuously fed by the nurse bees. As it grows, the amount of food in the cell also increases, making it easy to distinguish young larvae from more developed ones.

Observing open brood allows beekeepers to answer several important questions:

• Are there recent eggs?
• Are there larvae of different ages?
• Is the distribution continuous?
• Is the amount of brood consistent with the time of year?

These answers help interpret the queen's condition and the colony's development.

The absence of open brood does not always indicate a problem. Depending on the season, a natural queen replacement, or other circumstances, there may be temporary periods with little or no open brood. Comparing with previous inspections and other indicators helps understand the situation.

In stingless bees (meliponines), open brood has a different organization than that observed in Apis mellifera, but it still plays the same role: ensuring the renewal of the colony's population.

Note: Interpretation should consider the season, the colony's history, and other observed indicators.

A single newly laid egg indicates that the queen was present or laid eggs very recently, even if she is not observed during the inspection.

Recording the presence of eggs, open brood, and photos allows you to track the evolution of laying between inspections and identify changes that might otherwise go unnoticed.

If you stop observing open brood during several consecutive inspections or find significant changes in the appearance of the larvae, seek support from a beekeeping technician.

Spending a few minutes observing open brood provides valuable information about the queen's recent activity and the colony's ability to renew its population.

• What is Brood?
• What is Sealed Brood?
• How to Interpret the Brood Pattern?
• What Does the Absence of Eggs Mean?