Effect of Different Carbon Dioxide Gas Concentrations Used During the Insemination of Honey Bee Queens on Starting Oviposition
The experiment was conducted in 2004, 2005 and 2007 at the Research Institute of Pomology and Floriculture, Apiculture Division in Puławy, Poland. Carniolan sister queens at the age of 7 days were inseminated with an 8μl dose of semen. Queens were anesthetized once during the insemination with different concentrations of carbon dioxide and air gas mixtures. It took queens a shorter time to be narcotized when CO2 was given at higher concentrations. The timing was from 6.1 s when 100% CO2 was used to 95.5 s when 50% CO2 was used. Semen injection took longer in queens anaesthetized with CO2 at the lower 50% and 75% concentrations. The queens remained anesthetized significantly longer when higher CO2 concentrations were used.
Among 276 instrumentally inseminated queens, 88% started laying eggs before the end of the experiment and 12% did not start laying eggs, or died before the end of the experiment. The highest percentage of queens that did not start laying eggs or died was noted in the group anaesthetized with 75% and 80% of CO2 (16.4% and 14.5%). In the other groups, the percentage of queens who did not start laying eggs or died ranged from 7.4% to 14.5%. Different CO2 gas concentrations used for immobilization of bee queens during instrumental insemination significantly influenced oviposition of queens. Instrumentally inseminated bee queens began laying eggs 4 to 55 days after the insemination. The significantly shortest time from insemination to oviposition was noted in queens that were narcotized with 50, 100 and 90% of CO2 (17.4, 17.6 and 19.9 days respectively). The longest time was noted in queens treated with 75-80% of CO2 (after 22 days).