Figure 3.

Effects of exposing 36 hpf embryos to 4 h of either normoxia or anoxia on subsequent whole-body cortisol response to dyadic social interactions in adult zebrafish. (a) Pairs of adult zebrafish consisting of one fish each from the normoxia and anoxia embryonic treatments were allowed to interact for 1 h (n = 10). A significant difference is indicated by an asterisk (Welch two-sample t-test, p < 0.05). (b) Based on a behavioural assessment of the dyadic social interactions, each fish within a pair was assigned a dominant or subordinate status. A separate group of control adult fish from the normoxia embryonic treatment (n = 7) was used to quantify whole-body cortisol levels in the absence of dyadic social interactions. Values are mean + s.e.m. Significant differences are indicated by dissimilar letters (one-way ANOVA and Tukey's post hoc test, p < 0.05).