Bioassay for Diluents of Honey Bee Semen1

A bioassay was developed to evaluate diluents of honey bee ( Apis mellifera L.) semen. Using a simple diluent (1.1% NaCl, 0.1% glucose, 0.01% each L-arginine HCl, L-glutamic acid, L-lysine, 0.02% dihydrostreptomycin sulfate, and 0.012% penicillin G sodium in 0.05 M Tris buffer at pH 8.7), 100-fold dilution, incubation at 35 ± 1°C for 10 min. and reconcentration did not reduce the number of spermatozoa that reached the spermathecae of instrumentally inseminated queens. Undiluted control semen had a 10.9% transfer efficiency when 15 × 106 spermatozoa were injected into the oviducts of each queen. Treated groups of semen incubated for 0.17, 1.5, 3.0, 4.5, 6.0, 7.5, and 19.5 h had transfer efficiencies of 10.7, 8.8, 9.8, 5.1, 2.1, 4.3, and 2.4%, respectively.