ABRC2010 Effect of Transportation on Honey Bee Physiology

The following was presented at the 2010 American Bee Research Conference in Orlando, FL.

16. Huang, Z.Y., K. Ahn, J. Riddle & J. Pettis – EFFECT OF TRANSPORTATION ON HONEY BEE PHYSIOLOGY – Despite the requirement of long distance transportation of colonies for almond pollination, we understand little of the effects of the long distance transportation on bees. We conducted three trials to study the effects of transportation on honey bee physiology. For each trial, newly emerged bees from one colony were split into two groups and introduced into a M (migratory) or S (stationary) group – these M and S colonies form a colony pair (CP) with similar genetics but different experience in transportation. One trial was conducted in CA/FL, whereby S bees stayed in Bakersfield, CA but M bees were moved to FL (4,000 km, n=12 colonies / group). One trial was done in Boston, GA, where the M group were transported to MI, then back to GA (3,250 km, n=12 colonies / group). In both trials, bees were about one week old and experienced transportation 3-5 days old. A third trial was in E. Lansing, MI, where the M group was transported for 900 km per day for 3 days (n= 6 colonies / group). In the first 2 trials, only one cohort of bees were age marked before transportation, but in the 3rd trial, bees were sampled at 7 and 17 day olds (they experienced transportation when they were 3-6 and 13-16 days old, respectively).

We measured the following parameters: juvenile hormone titers (JH) in hemolymph, lipid content in the abdomen, total protein in head or thorax, and sizes of hypopharyngeal gland (HPG) acini. HPG sizes were significantly smaller in migratory colonies. These were true for all three locations, and also for young and old bees in the Michigan trial (Table). This might be due to workers unable to consume pollen normally while being transported, which affected their gland sizes adversely. All other parameters (JH, lipids and total protein in heads or thorax) were either not as sensitive, or inconsistent. We were surprised to find that 1) JH titer was not significantly higher in the M group, and 2) that 17 day-old bees were still affected by migration, even though their HPG should have attained maximum sizes around day 8-12.

Table – Brief summary of analysis of variance (ANOVA) and analyses by individual colony pairs (CP). NS=no significant, with P>0.05.

CA
JH lipids Head/thorax protein HPG sizes
2 out of 11 CP significant. ANOVA: NS 2 out of 4 CP with higher lipids in S, the other 2 reversed. ANOVA: NS Not measured 7 out of 9 CP showed larger glands in S group. ANOVA: P<0.01
GA
2 out of 12 CP significant. ANOVA: NS 1 out of 4 CP with higher lipids in S. ANOVA: NS 9 CP analyzed. ANOVA: NS for thorax protein, but P<0.01 for head protein. 4 out of 4 CP showed larger glands in S group. ANOVA: P<0.01
MI (Young cohort, 7 days old)
2 out of 6 CP had higher JH in M. ANOVA: NS 5 out of 6 CP with higher lipids in S. ANOVA: P<0.01 6 CP analyzed. ANOVA: NS 4 out of 6 CP showed larger glands in S group. ANOVA: P<0.01
MI (older cohort, 17 days old)
2 out of 6 CP had higher JH in M. ANOVA: NS ANOVA: NS 6 CP analyzed. O ANOVA: NS 3 out of 6 CP showed larger glands in S group. ANOVA: P<0.01

More presentations from this conference can be found at Proceedings of the American Bee Research Conference 2010