Direct yolk sac volume manipulation of zebrafish embryos and the relationship between offspring size and yolk sac volume

Abstract

Through direct manipulation of yolk sac volume (Vy), in the zebrafish Danio rerio, Vy and offspring size was positively correlated and the relationship was independent of geographical location, parental size or age and, most importantly, parental genetic factors. Larval survivorship, under a non‐feeding regime and up until hatch, was not significantly affected by the manipulation. Decreased Vy significantly decreased maximum standard length (LS), maximum body surface area (AB), time to yolk sac absorption, LS and AB at yolk sac absorption, and the LS and AB at starvation. The methodology of Vy adjustment will be useful for the studies of the interaction between early life‐history traits and offspring size, egg quality variables and early vertebrate development.