Fig. 4

a Zebrafish larvae were raised in egg water containing 1.5% EtOH at 4 dpf and cultured for 24 h. The control group was raised without EtOH exposure for comparison. Both groups of larvae were imaged and digitally reconstructed at 5 dpf to compare and evaluate the morphological abnormalities induced by EtOH. b, c Qualitative 3D morphological assessment of zebrafish larvae by comparing the 3D reconstructed models of three zebrafish larvae from the control group (b) and from the 1.5%-EtOH group (c), respectively. The reconstructed 3D models show that acute EtOH exposure can induce morphological abnormalities in the zebrafish body, which includes edema and tail curling. d Distribution of normal vectors on the surface of reconstructed 3D models of a zebrafish larva from the control group and 1.5%-EtOH group, respectively. e Distributions of the angle (θ) between normal vectors and the x-axis for 3D models of a larva of control group and three larvae of 1.5%-EtOH group with increasing degrees of edema and tail curling. The angles of the anterior two thirds and posterior one third of the larva are calculated to quantify the level of edema and tail curling, respectively. With larger deformations, the angles have a wider distribution based on the histogram and Gaussian fitting curve, as reflected on the value of the variance (σ2). The “abnormality factor” (𝑅=𝜎2/𝜎20) shows the degree of morphological abnormalities by calculating the ratio of variances in the larvae of the 1.5%-EtOH group (σ2) and the averaged variance of the control group (𝜎20𝐸=0.0237±0.0091 and 𝜎20𝑇=0.0085±0.0032; n = 15). Scale bar: 1 mm. Source data is available as a source data file.