Hypopharyngeal Gland
Lexikon
The brood food glands, also called hypopharynx or hypopharyngeal glands, lie as a pair in the worker's head.
The brood food glands, also called hypopharynx or hypopharyngeal glands, lie as a pair in the worker's head. They develop in the first days of life and reach their peak activity from about the sixth to the twelfth day of life, exactly the time when the bee works as a nurse bee. At this stage she produces a brood food rich in protein, fat, and vitamins, with which the larvae and the queen are fed; mixed with secretions from the mandibular glands, it becomes the queen food known as royal jelly.
As the bee gets older, the brood food glands regress and switch their production to other enzymes that help process sugar and honey. This change is reversible, however: if the colony suddenly lacks young nurse bees, for example after a heavy loss of house bees, older workers can also reactivate their brood food glands and take up brood care again.
In practice it is crucial that every expansion of the brood nest, every split, and every addition of open brood requires enough bees with active brood food glands. If this potential is lacking, brood is fed inadequately or even removed again. A common mistake is to look only at the number of bees on a comb without considering what proportion of them is actually at the right physiological age for nursing.