Levitan D R, Sewell M A, Chia F S
Biol Bull. 1991 Dec;181(3):371-378. doi: 10.2307/1542357.
Determining fertilization success of free spawning organisms in the field requires knowledge of how eggs and sperm interact under varying encounter frequencies and durations. In the laboratory, we investigated the relative influence of sperm concentration, egg concentration, sperm-egg contact time, and sperm age on fertilization in the sea urchin Strongylocentrotus franciscanus. Our results indicated that sperm concentration, sperm-egg contact time, sperm age, and individual variability were sequentially the most important factors influencing fertilization success. Egg concentration was not significant over the range tested. A theoretical model of fertilization (Vogel-Czihak-Chang-Wolf model) was used to estimate the two rate constants of fertilization kinetics: the rate constant of sperm-egg encounter and rate constant of fertilization. This model explained 91% of the variation in fertilization success, provided estimates of the rate constants involved in fertilization, and indicated the proportion (3%) of sperm-egg contacts that result in fertilization. Estimates of sperm swimming velocity and egg diameter were used to independently calculate the rate of sperm-egg encounter and confirm the predictions of the model. This model also predicts the non-significant effect of egg concentration on fertilization success found empirically.
确定野外自由产卵生物的受精成功率需要了解卵子和精子在不同相遇频率和持续时间下如何相互作用。在实验室中，我们研究了精子浓度、卵子浓度、精卵接触时间和精子年龄对海胆强壮拟球海胆受精的相对影响。我们的结果表明，精子浓度、精卵接触时间、精子年龄和个体变异性依次是影响受精成功率的最重要因素。在所测试的范围内，卵子浓度并不显著。使用受精理论模型（Vogel-Czihak-Chang-Wolf模型）来估计受精动力学的两个速率常数：精卵相遇速率常数和受精速率常数。该模型解释了受精成功率变化的91%，提供了受精过程中涉及的速率常数估计值，并指出了导致受精的精卵接触比例（3%）。精子游动速度和卵子直径的估计值被用于独立计算精卵相遇速率，并证实模型的预测。该模型还预测了从实验中发现的卵子浓度对受精成功率的非显著影响。
