Efficiency of Artificial Insemination for Breeding Apis cerana in Korea

Control mating is very important aspect in bee breeding programs. The technique of artificial insemination is the possible one that can surely control mating of the selected drones with the virgin queen. This is the first time applied this technique with A. cerana in Korea. Altogether 18 queens were artificially inseminated, and 2,000 drones of A. cerana both from Korea and Vietnam were used to evaluate amount of semen collection. Semen from Apis mellifera also was collected as a comparison. Semen of A. cerana is much difficult to separate from mucus in comparing with A. mellifera. The average amount of semen can be collected from one Korean A. cerana drone was 0.09μl and 0.1μl of Vietnamese one, whereas the A. mellifera was more than 6 times (0.58μl semen per A. mellifera drone). Obtaining 1μl of semen have to collect from 11.94 drones that successful semen ejection and have to kill 17 drones of Korean A. cerana. Queens artificially inseminated with 4μl of semen (once insemination) or 8μl of semen (twice insemination, each with 4μl of semen) started laying egg later than naturally mated queens 5.3 and 2.5 days, respectively. The onsets of oviposition of artificially inseminated queens were 12.5 to 15.3 days. Queens received twice inseminations started laying eggs 2.8 days earlier than those received only once insemination. Artificially inseminated queens produced exclusively brood and were similar as the naturally mated ones. The brood production of the queens received once insemination with 4μl of semen was insignificantly different than those received twice inseminations or naturally mated ones, suggesting that one artificial insemination with 4μl of semen is favorable.