Regulation of sperm motility in Eastern oyster (Crassostrea virginica) spawning naturally in seawater with low salinity
Fig 4
Effect of pH on sperm velocity (μm/s, A) in Eastern oyster, Crassostrea virginica. Sperm motility was assessed in artificial seawater buffered with 20 mM MES, HEPES or Tris, pH 6.5–10.5. Average motility at each pH (B) and time post-activation (C) is displayed. D shows a second-order polynomial regression for the effects of pH on sperm velocity at 15 min post-activation. Data were analyzed using a repeated measures ANOVA and shown as mean ± SE (n = 4). Treatments with different superscripts significantly differ (p < 0.05). A velocity of 0 μm/s was indicated by asterisk.