Stimulatory effect of flight training across time: Long-term effect of flight-training (H1b)
Circulating oxidative status was similar between untrained and flight-trained birds (Fig. 2A, Table S1; Training: d-ROMs, T279 = -0.400, P = 0.690, OXY, T279 = 0.623, P = 0.534) at the start and end of the experiment (BG vs RC: d-ROMs, T90 = 0.054, P = 0.957, OXY, T90= -0.069, P = 0.945) suggesting that 15 days of flight training did not have substantial long-term effects on plasma oxidative status. However, the change in plasma d-ROMs over time (i.e., the difference from RC to BG) decreased more in flight-trained compared to untrained birds (Table S2; Δ During Training d-ROMs, T89 = -2.025, P = 0.046); we detected no such differences in change in OXY over time within individuals in relation to flight training (Δ During Training OXY, T89 = 0.982, P = 0.329). These results provide partial evidence for H1b (Long-term effects of flying) as d-ROMs decreased over the course of several weeks of flying within flight-trained birds compared to untrained birds.