Fig. 5

Rotenone exposure induced motor symptoms in developing zebrafish embryos. Wild-type embryos aged 7–8 h post fertilization (hpf) were exposed with 30 nM rotenone to 72 hpf for thigmotaxis, and to 120 hpf for free locomotion. (A) Illustration of the thigmotaxis method. (B) Representative images and the quantification of thigmotaxis as (C) distance (cm), and (D) velocity (cms-1) after the touch response test at 72 hpf, N = 36. (E) Representative images of free locomotive movement at 120 hpf and its (E) swim paths. Quantification of the free locomotion movement as (F) distance and (G) velocity. (H) Representative images of the swim paths after agitation challenge at 120 hpf and quantification of the track length as (I) distance (cm) and (J) velocity (cms-1), N = 36. (K, M) Embryos acclimatized to the dark for 10 min and started alternative light and dark cycles of 5 min for 30 min, (K) Quantification of the free locomotion as distance (cm) in alternative light and dark conditions at 72 (N = 36) and (M) 120 hpf (N = 24), light exposure is denoted by white color background and dark is denoted by ash color blocks of the graphs. Swin paths at 5 min for a light and 6 min for a dark at (L) 72 and (N) 120 hpf. Data presented as the mean ± SD. SD: standard deviation. * p < 0.05, * * p < 0.01, * ** p < 0.001, ns: not significant.,.