Effects of parental treatment on zebrafish larvae cortisol stress response. Cortisol levels after a 20 min exposure to (A) combined elevated temperature and hypoxia (offspring combined exposure), (B) a swirling stressor (offspring swirl) or control conditions (offspring control) in 5 days post-fertilization (dpf) larvae derived from adult zebrafish exposed to either control or combined exposure conditions for 14 days. Cortisol levels were compared with two-way ANOVAs followed by post hoc Holm–Šidák tests (A: square-root transformed, parental exposure: P=0.014; larval exposure: P=0.002; parental exposure×larval exposure: P=0.205; B: parental exposure: P=0.973; larval exposure: P<0.001; parental exposure×larval exposure: P=0.374). Differences within treatments across exposure at 5 dpf are indicated by different letters. Differences between treatments for a given exposure at 5 dpf are indicated by an asterisk. Data are means±s.e.m. (all n=6; except combined exposure larvae, swirl, where n=5).
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