DEPLETION OF DEAD SPERMATOZOA DID NOT SUFFICIENTLY IMPROVE THE QUALITY OF RAM SEMEN: SHORT COMMUNICATION

The main objective of this study was to improve the motility and overall quality of spermatozoa from the fresh ram semen samples using more sensitive depletion programmes of AutoMACS Pro Separator to remove dead sperm cells. Briefly, ram spermatozoa, given either at high (108) or low (107) concentrations, were incubated with the Dead Cell Removal kit reagent and magnetically sorted using two very sensitive depletion programmes (Depl05 and Depl025) with different sample loading rates. Fresh unsorted semen samples (control) as well as both sorted fractions (negative and positive) were analysed using computer-assisted sperm assay (CASA) to assess the motility parameters and using flow cytometry to evaluate the proportion of dead cells and overall magnetic-activated cell sorting (MACS) efficiency. We obtained significantly (P \u003c 0.01) lower percentage of dead spermatozoa only after sorting the high concentrated spermatozoa using a Depl025 programme compared to control samples. However, the negative fractions still contained more than 20 % of dead cells irrespective of the sorting programme used. In addition, the motility parameters were significantly improved neither by the used sorting strategy nor by the adjustment of spermatozoa concentration. In conclusion, further optimization of this method is required in order to sufficiently remove dead spermatozoa and to improve the spermatozoa motility.