Abstract:
The poor health status of the Western honey bee, Apis mellifera, compared to its Eastern
counterpart, Apis cerana, is remarkable. This has been attributed to lower pathogen prevalence
in A. cerana colonies and to their ability to survive infestations with the ectoparasitic
mite, Varroa destructor. These properties have been linked to an enhanced removal of
dead or unhealthy immature bees by adult workers in this species. Although such hygienic
behavior is known to contribute to honey bee colony health, comparative data of A. mellifera
and A. cerana in performing this task are scarce. Here, we compare for the first time the
removal of freeze-killed brood in one population of each species and over two seasons in
China. Our results show that A. cerana was significantly faster than A. mellifera at both
opening cell caps and removing freeze-killed brood. The fast detection and removal of diseased
brood is likely to limit the proliferation of pathogenic agents. Given our results can be
generalized to the species level, a rapid hygienic response could contribute to the better
health of A. cerana. Promoting the fast detection and removal of worker brood through
adapted breeding programs could further improve the social immunity of A. mellifera colonies
and contribute to a better health status of the Western honey bee worldwide.