4.2.2. Inoculation with diseased brood
If it is not important to inoculate colonies with a known quantity of spores (e.g. if the goal of the experiment is simply to induce clinical symptoms of AFB), a comb section (15 cm x 15 cm) can be cut from frames containing infective AFB scales (dried spores). At least 50 % of the cells should contain scale. Introduce the comb sections with AFB scale into the middle frame in each colony.