Issue |
Apidologie
Volume 32, Number 1, January-February 2001
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Page(s) | 91 - 103 | |
DOI | https://doi.org/10.1051/apido:2001114 |
Apidologie 32 (2001) 91-103
Honey bee age-dependent resistance against American foulbrood
Karl Crailsheim and Ulrike Riessberger-GalléInstitut für Zoologie an der Karl-Franzens Universität Graz, Universitätsplatz 2, 8010 Graz, Austria
(Received 2 August 2000; revised 27 October 2000; accepted 31 October 2000)
Abstract
American foulbrood is a fatal disease of honeybee larvae. Larvae become infected by
swallowing spores of P. larvae larvae that contaminate their food. Adult bees who
transfer the spores and have close contact with larvae never become infected. Resistance
to this bacterium was investigated in various larval stages and in adults of different
ages. Substances inhibiting the growth of P. larvae larvae could be demonstrated in
4 day old larvae and, to a lesser extent, in 1 day old larvae. No such substances
could be shown in 6 day old larvae. Extracts of midguts of adult bees generally showed
a stronger ability to inhibit growth of the bacteria than did extracts of larvae. It was
discovered that the midguts of 8 day old adult bees show a higher growth-inhibiting
potential against P. larvae larvae than midguts of freshly emerged adult bees or foragers.
Key words: Apis mellifera / Paenibacillus larvae larvae / age-dependent resistance / honeybee larvae
Correspondence and reprints: Karl Crailsheim
e-mail: karl.crailsheim@kfunigraz.ac.at
© INRA, EDP Sciences, DIB, AGIB 2001