The total basal respiration (OCR, in pmol O2/min/embryo) during the development of a single zebrafish embryo in the blastula (3 hpf), gastrula (7 hpf), segmentation (12 hpf), segmentation/pharyngula transition (24 hpf), mid-pharyngula (36 hpf), and hatching (48 hpf) stages inside a microfluidic device. (Mean ± SEM; n = 4 from 2 × 2 microwells).