Number of spermatozoa in the spermatheca of honey bee queens inseminated with small doses of semen and kept in an incubator in cages with different numbers of workers

Abstract

In mass production, instrumentally inseminated honey bee queens are usually kept in mailing cages with a low number of workers and inseminated with small doses of semen. Inseminated queens should have more than 4 mln sperms in their spermatheca. The aim of this study was to investigate the number of spermatozoa entering the spermatheca of queens inseminated with different small doses of semen. Ninety queens were divided into six groups and inseminated as follows: 1 μl, 2 μl or 3 μ of semen at the age of 7 days and 2 x 1 μ, 2 x 2 μl or 2 x 3 μ at the age of 7 and 9 days. Queens were kept in the mailing cages with 15 or 25 attendant bees before and after instrumental insemination. No significant differences were found in mortality and the condition of oviducts of queens inseminated with different small doses of semen and kept in cages with 15 or 25 workers. Queens inseminated with 2 x 2 μ of semen had significantly less sperms in their spermatheca than those inseminated with 2 x 3 μl but significantly more than 2 x l μ and 1 μl, 2 μ or 3 μl. The smallest dose of semen used for instrumental insemination of honey bee queens should be 2 x 3 Significant differences in the number of spermatozoa in the spematheca of queens kept with 15 or 25 attendant bees were not found.