Freeze killed brood assay ineffective in predicting mite load in colonies
Oh crum, new study finds "Freeze Killed Brood" assay ineffective at predicting colony mite load.
The FKB assay (brood cells are killed with liquid nitrogen within a ring, and then counted for clearing at 24 hours) is widely used as a proxy for "hygenic behavior". The protocol is core to the selection of "Minnesota Hygenic Bees". However a replication of the protocol in an unselected population show no correlation with mite loading. They assay is ineffective in detecting resistant bees.
Cite: Hygienic removal of freeze-killed brood does not predict Varroa-resistance traits in unselected stocks
Gil Leclercq Journal of Apicultural Research, 2018
Vol. 57, No. 2, 292–299
The situation in our unselected stocks is summarized as:
(1) We found no significant correlation between the
mite load and the FKB removal at 24 h (nor at 48 h). In
future studies, other periods of time should probably
also be tested