percent of the bee bread samples from susceptible colonies were positive, whereas 65 % from resistant colonies were. Sixty-four percent of the guts of nurse bees sampled from susceptible colonies were positive, and 25 % from resistant colonies were. NELSON and also found A. stored in comb (1982)OCHNAUERG apis in pollen cells of colonies with chalkbrood and in the guts of adult bees from infected colonies. The presence of A. apis in guts of nurse bees would result from consumption of contaminated pollen. Higher percentages and more types of samples from susceptible colonies than from resistant colonies contained A. apis. For example, A. apis was cultured from the interior of 40 % of capped larvae and 16 % of uncapped larvae sampled from susceptible colonies but 0 % of capped larvae and 5 % of uncapped larvae from resistant colonies. The fungus was also isolated from brood food and honey from susceptible colonies only. Thus, our limited data from colonies that were sprayed with A. apis indicate that the fungus contaminates more diverse substrates and survives better in bees and hive products from colonies that exhibit poor hygienic behavior. Additional unpublished data ILLIAM(G,1981) revealed A. apis in bees and hive products from some colonies for as long as 5 months after the spraying had ceased. An interesting observation in the present study was the discovery of 8 pupae mummified by A. apis. In earlier work, we noted that pupae did not support the growth of A. apis in laboratory experiments (GtLt,tnvt et al., 1978). Thus, it is
possible that the mummified pupae became infected as prepupae but somehow were
able to develop into pupae before death occurred. The mummies were smaller than
normal pupae but maintained body integrity indicating that they may have been
subnormal in some that allowed them to become mummified.
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