The sperm quality of honey bee drones is assessed by the motility, viability and concentration of spermatozoa. The morphology of the sperm nucleus is of great importance for fertilization. The most objective indicators of sperm nucleus morphology are the size and shape of the head. The purpose of the research is to study morphometric parameters of spermatozoa of honey bee drones Apis mellifera L. in the assessment of sperm quality. We harvested semen by artificial stimulation of endophallus eversion from sexually mature drones at the age of 22–30 days using SCHLEY-System artificial insemination equipment model 1.04. For the first time, we used honey diluent for sperm dilution, and fixation was performed using Diff Quick. We assessed spermatozoa for motility, concentration, and viability. We studied the following morphometric parameters: acrosome length (3.8–4.3 μm), nucleus length (5.2–5.5 μm), nucleus perimeter (11.7–12.2 μm), and area (5.0–6.2 μm). There was a correlation between morphometric parameters of spermatozoa and qualitative characteristics of sperm (r = -0,4-0,3 with p ˂ 0,05). We noted the most stable relationship between total sperm motility, their nucleus length (r = -0.3 at p ˂ 0.05) and nucleus area of the heads (r = -0.2, r = -0.3 at p ˂ 0.05). As studies have shown, the choice of sperm diluent (z = -5.8; z = -15.4; z = -7.3) is of great importance for the study of spermatozoa morphometric parameters. The main characteristics of drones’ spermatozoa are influenced by seasonality. The results of studies in 2020 showed the best sperm quality in the drones of the summer generation (t = 6.0; t = 14.3; t = 2.4), and in 2021 – in the spring generation (t = 6.2; t = 6.3; t = 5.5). The reason could be natural and climatic conditions of the area, which influenced the diet of drones
Keywords
Drone, sperm morphometry, sperm motility, sperm viability