Comparison of yolk coloration and morphological deformities between progeny of adults that were fed decapsulated brine shrimp cysts (Decap-fed) and progeny of adults that were not fed decapsulated brine shrimp cysts (Decap-free). (A–C) Progeny of Decap-free adults exhibited clear or pale yellow yolks and normal morphological features. Low (A) and high (A′) magnification of 5–7 hpf embryos. Lateral (B) and ventral (B′) views of 1 dpf embryos. (C) Lateral view of a 5 dpf larva with normal inflated swim bladder (arrow), cardiac sac (white arrowhead and inset, enlarged 200%), and pale-yellow yolk (black arrowhead). (D–F) Progeny of Decap-fed adults exhibited orange coloration in yolks and abnormal morphological features. Low (D) and high (D′) magnification of 5–7 hpf embryos with orange-colored yolks. Lateral (E) and ventral (E′) views of 1 dpf embryos, which continued to exhibit orange coloration in the yolk and yolk extension. (F) Lateral view of a 5 dpf larva that appeared developmentally delayed with an uninflated swim bladder (arrow), cardiac edema (white arrowhead and inset, enlarged 200%), and an enlarged orange-colored yolk (black arrowhead). Scale bars = 1 mm (A applies to A and D; A′ applies to A′, B, B′, D′, E, and E′; C applies to C and F). Hours postfertilization, hpf; days postfertilization, dpf.

Gross morphological differences between clutch mate larvae reared in dark and light conditions. Progeny of adult zebrafish that were fed decapsulated brine shrimp cysts were raised either in complete darkness (Dark-reared) or under a normal 14-h light/10-h dark cycle (Light-reared), and larvae were compared at 5 dpf. (A) Dark-reared larvae were developmentally delayed and exhibited cardiac edema and enlarged orange-colored yolks, but typically maintained equilibrium and were motile. (B) Light-reared larvae exhibited gross morphological and developmental defects, were unable to maintain equilibrium along the transverse axis, and were mostly immotile. Scale bar = 1 mm. Days postfertilization, dpf.