This standard sort of procedure will indicate which colonies are most
hygenic, in how quickly or completely they remove *dead brood*,
specifically, freeze-killed brood.  It is dead brood, but not AFB-killed
brood.  There are other factors with AFB-killed brood, such as the
consistency of the brood (stage of decomposition) and the remaining scales
which contaminate the cells.
 
Ideally, AFB brood would be introduced and the colonies monitored as to the
amount of cleaning up they do.  Whether they succumb to AFB after that is
another question.  Some colonies can be given rancid AFB brood-combs, clean
them up, and use them without immediate disease manifestation.  According
to Roger Morse, this shows that stress is another crucial factor in whether
or not a colony "gets" AFB.
 
>I just want to pass on an idea given by Susan Cobey, to test resistance
>of bees to AFB. As you might know, the original test involved cutting a
>square of comb with capped brood, then put it in the freezer and then
>return it to the hole left in the original comb. If the bees cleaned all
>the dead brood, they were "resistant" to AFB, if not, they would be
>highly susceptible.
>The modification consists of pinning the square of brood, so to kill the
>larvae, but without the neccessity to remove and put back the comb.
>This way, she can select for resistant bees to AFB.