Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany.
J Fish Biol. 2010 Aug;77(3):552-69. doi: 10.1111/j.1095-8649.2010.02698.x.
Size-dependent reproductive success of wild zebrafish Danio rerio was studied under controlled conditions in the laboratory to further understand the influence of spawner body size on reproductive output and egg and larval traits. Three different spawner size categories attained by size-selective harvesting of the F(1)-offspring of wild D. rerio were established and their reproductive performance compared during a 5 day period. As to be expected, large females spawned more frequently and had significantly greater clutch sizes than small females. Contrary to expectations, small females produced larger eggs when measured as egg diameter with similar amounts of yolk compared to eggs spawned by large spawners. Eggs from small fish, however, suffered from higher egg mortality than the eggs of large individuals. Embryos from small-sized spawners also hatched later than offspring from eggs laid by large females. Larval standard length (L(S))-at-hatch did not differ between the size categories, but the offspring of the large fish had significantly larger area-at-hatch and greater yolk-sac volume indicating better condition. Offspring growth rates were generally similar between offspring from all size categories, but they were significantly higher for offspring spawned by small females in terms of L(S) between days 60 and 90 post-fertilization. Despite temporarily higher growth rates among the small fish offspring, the smaller energy reserves at hatching translated into lower condition later in ontogeny. It appeared that the influence of spawner body size on egg and larval traits was relatively pronounced early in development and seemed to remain in terms of condition, but not in growth, after the onset of exogenous feeding. Further studies are needed to explore the mechanisms behind the differences in offspring quality between large- and small-sized spawners by disentangling size-dependent maternal and paternal effects on reproductive variables in D. rerio.
在实验室的控制条件下，研究了野生斑马鱼 Danio rerio 的体型依赖性繁殖成功，以进一步了解亲鱼体型对繁殖产出以及卵和幼鱼特征的影响。通过选择性收获野生 D. rerio 的 F1 后代，建立了三个不同的亲鱼体型类别，并在 5 天的时间内比较了它们的繁殖性能。正如预期的那样，大型雌鱼产卵更频繁，且产卵量明显大于小型雌鱼。与预期相反，当以卵径测量时，小型雌鱼所产的卵比大型亲鱼所产的卵具有更大的卵直径，但蛋黄量相似。然而，小鱼的卵死亡率高于大型个体的卵。来自小型亲鱼的胚胎也比来自大型雌鱼产卵的胚胎孵化较晚。孵化时的幼鱼标准体长（L(S)）在不同体型类别之间没有差异，但大型亲鱼的后代具有显著更大的孵化时面积和更大的卵黄囊体积，表明条件更好。尽管所有体型类别的后代的生长率通常相似，但在孵化后 60 至 90 天之间，来自小型雌鱼产卵的后代的生长率明显更高。尽管小鱼后代的生长率暂时较高，但在胚胎发生后期，孵化时的较小能量储备转化为较低的条件。亲鱼体型对卵和幼鱼特征的影响似乎在早期发育阶段相对明显，并且在外部喂养开始后，在条件方面似乎仍然存在，而不是在生长方面。需要进一步的研究来探索在 D. rerio 中，大型和亲鱼体型之间后代质量差异的机制，通过分离体型依赖性母体和父体效应对繁殖变量的影响。
