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 ( V y ), in the zebrafish Danio rerio , V y 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 V y significantly decreased maximum standard length ( L S ), maximum body surface area ( A B ), time to yolk sac absorption, L S and A B at yolk sac absorption, and the L S and A B at starvation. The methodology of V y 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.