Table 1.
Kinematic variables (mean ± SEM) of the four sperm sub-populations (SPs) defined at 60 min post-thawing bull semen samples.
| Sub-Population | SP1 | SP2 | SP3 | SP4 |
|---|---|---|---|---|
| Number of cells (%) | 1300 (20.02) | 1837 (28.29) | 1243 (19.14) | 2113 (32.54) |
| VCL | 120.93 ± 1.2a | 140.10 ± 1.02b | 108.41 ± 1.23c | 141.78 ± 0.95b |
| VSL | 77.30 ± 1.12a | 118.29 ± 0.94b | 52.60 ± 1.14c | 105.79 ± 0.87d |
| VAP | 86.97 ± 1.01a | 120.03 ± 0.85b | 67.37 ± 1.03c | 106.67 ± 0.79d |
| LIN | 60.90 ± 0.58a | 80.80 ± 0.49b | 49.56 ± 0.59c | 75.39 ± 0.46d |
| STR | 82.05 ± 0.49a | 92.73 ± 0.41b | 77.37 ± 0.50c | 95.72 ± 0.39d |
| WOB | 70.36 ± 0.44a | 83.75 ± 0.37b | 62.42 ± 0.45c | 76.87 ± 0.34d |
| ALH | 3.71 ± 0.04a | 3.28 ± 0.03b | 3.89 ± 0.04c | 3.93 ± 0.03c |
| BCF | 9.17 ± 0.10a | 8.97 ± 0.08a | 8.13 ± 0.10b | 11.32 ± 0.08c |
SP1: medium velocity and linear-progressive; SP2: fast linear-progressive and oscillatory; SP3: slow nonlinear, non-progressive, and non-undulatory; SP4: fast linear-progressive and undulatory. Number of cells = 6493. VCL = curvilinear velocity (µm·s−1); VSL = straight-line velocity (µm·s−1); VAP = average path velocity (µm·s−1); LIN = linearity of forward progression (%); STR = straightness (%); WOB = wobble (%); ALH = amplitude of lateral head displacement (µm); BCF = beat-cross frequency (Hz). SEM = standard error of the mean. a-d Different letters indicate differences between sperm SPs. p < 0.05.