Incubation conditions

Researchers should attempt to maintain their experimental bees in optimal conditions for both host and parasite, and should consider the possible effects of growth chamber conditions, as environmental conditions can have a large influence on both host susceptibility and parasite virulence (e.g. Kraus and Velthuis, 1997; Ferguson and Read, 2002; McMullan and Brown, 2005).  Although few data exist on the effects of specific temperatures on Nosema parasitism in honey bees, it is clear that intra-host development of both parasites in European honey bees, as well as spore viability, can be affected by temperature (e.g. Malone et al., 2001; Fenoy et al., 2009; Martín-Hernández et al., 2009; Fries, 2010; Higes et al., 2010).

Adult workers should be maintained in complete darkness at 30 °C and approximately 60-70 % RH in a growth chamber or incubator with adequate ventilation. A data logger should be used to record both temperature and relative humidity within the incubator during the course of each experiment.  These data will ensure adequate conditions were maintained, and may explain deviations from expected results during changes in incubator conditions as a result of mechanical problems or changes in ambient conditions. See the BEEBOOK paper on maintaining workers in cages (Williams et al., 2013) for more details.