Effect of depletion tests (DT) on the composition of boar semen

We conducted two depletion tests during the summer (DT 1) and winter (DT 2) to study their effect on selected biochemical parameters of boar semen. We subjected three boars to DT for 10 consecutive days. The first 3 days (Period 1) of ejaculate collections represented the reserves of the extragonadal spermatozoa and accessory sex gland secretions, whereas the other seven days (Period 2) represented the daily spermatozoa output and the secretory capacity of the accessory sex glands. We observed noticeable changes in the quantity and quality of the semen in DT 1 and 2. There was an increase in the number of spermatozoa with morphological defects, particularly coiled tails and detached acrosomes. The secretory activity of the accessory sex glands, particularly the vesicular glands, was slightly influenced by season. Depletion tests caused disturbances in the qualitative relations of secretions of the accessory sex glands, which were related to changes in the sperm plasmalemma integrity. These tests can be used to determine the total spermatozoa output, and to assess the secretory capacity of the accessory sex glands of boars.