Good afternoon everybody

This was one of the main topics on Apimondia Congress at Kiev.
Jeff Pettis talked about his investigations on 23 drone laying queens. 64% 
was fully inseminated and 36 % poorly. He found and average of 62% of dead 
sperm compared to normal queens around 15%.

Here it is the abstract published in the Apimondia Congress' book.

The Role Of Pesticides In Queen Health & Sperm Viability
USDA Agricultural Research Service
Bldg 306 BARC-E 10300 Baltimore Ave, Beltsville, 20705, USA
Dr. Jeff Pettis 301 504-7299, jeff.pettis ars.usda.gov

In honeybees, queen health is vital to the survival of the colony. In many 
parts of the world queens are failing or being superseded after as little as 
six month instead of the 1-2 year life span that is often reported. To 
explore possible causes of queen failure we disssected queens from failing 
colonies, including drone laying queens and measured mating success and 
sperm viability. Additionally, we treated healthy queens with various low 
doses of pesticides, based on the amounts found in adult bees and wax, and 
then measured sperm viability. We found that many drone laying queens still 
had sperm present but at a mortality rate above normal. Similarly, we found 
that queens from failing colonies had high sperm mortality compared to 
queens in healthy colonies. Lastly, when we artificially treated queens with 
sub-letal dosages of pesticides we could kill up to 50% of sperm in only 7 
days. Experiments are underway to look at the relationship between failing 
colonies, poor brood patterns and sperm viability. We have demostrated that 
queens from failing colonies can have high leves of dead sperm. Experiments 
are underway to look at booth pesticide exposures to drones and or mated 
queens to determine the source of the dying sperm relative to pesticide 
exposure. We hope to be able to report on the role that several pesticides 
may play in sperm viability and queen survivorship. We have data to support 
the conclusion that queens in failing colonies have high levels of dead 
sperm; the possible reasons, including pesticide exposure, for the dying 
sperm will be discussed.

best regards
fernando
Córdoba - Arg. 

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