Yes, although it's not as specific as a mammalian immune system, insects
   have some individual capability to combat microorganisms.
   Some insect blood cells react on contact with non-self objects, by
   changing to melanin (or is it chitin?), the dark tough material usually
   found in the insect's exoskeleton. The result is isolation of the
   foreign object inside a nodule or capsule within the insect.
 
   Insects also have some capability to metabolize or de-toxify chemicals,
   and that ability can be increased by exposure.
   The microorganism-resisting capability can similarly be stimulated by
   exposure, although it's not as specific or powerful as a mammalian
   immune reaction.
 
   I don't know whether it is of any significance for beekeepers and bee
   diseases.
 
   A few years ago when we were examining thousands of honey bee worker
   thorax sections, occasionally (less than 1 in 100) we found samples with
   many dark inclusions within the thorax muscles. They were quite similar
   to each other within the same bee, but some were irregularly rounded
   while others were spikule shaped (rods joined at a central point). The
   bee colonies were not obviously affected, and at that time had neither
   tracheal nor varroa mites.
 
   I sent some to a lab in the UK which had published on "encapsulation" to
   see if that's what they were, but never got a confirmation.
 
   Have any of you other bee slicers seen the same, or found another or
   more specific explanation?
 
   Kerry Clark, Apiculture Specialist
   B.C. Ministry of Agriculture, Fisheries and Food
   1201 103 Ave
   Dawson Creek B.C.
        V1G 4J2  CANADA          Tel (250) 784-2231     fax (250) 784-2299
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