Comparison of Different Sperm Selection Techniques in Ram Frozen-Thawed Sperm

ABSTRACT

Background: The success of fertilization is directly associated with semen quality and the sperm preparation. Considering the common use of cryopreserved spermatozoa, there is a need to develop strategies for sperm preparation in order to achieve a sperm sample of high quality through a rigorous selection of sperm. Thus, sperm cells are being more extensively investigate. This study aimed evaluating the influence of different sperm selection techniques on ram sperm parameters in semen preparation.Materials, Methods & Results: Frozen-thawed commercial semen from 10 Santa Inês rams was subjected to either swim-up, Percoll, mini-Percoll, sperm washing by centrifugation or a control group. After each technique, samples were incubated at 37C for 1 h, 2 h and 3 h. At post-selection moment (0 h) and at each interval, sperm recovery rate, motility, capacitation and plasma membrane (PM) integrity were analyzed. The lowest (P 0.05) recovery rate was recorded after swim-up (1.0 ± 0.3%), whilst the others were similar (P > 0.05). Most part of motility parameters were not affected (P > 0.05) by the technique at 0 h; just swim-up obtained higher (P 0.05) values for VSL (41.8 ± 11.1) and VAP (46.9 ± 11.2). Overall, swim-up presented higher (P 0.05) values for most of motility parameters over time of incubation. The control group led to more (P 0.05) capacitated