Table 4.

Whole blood and plasma cortisol values (mean ± SE) in rainbow trout sampled before and after exposure to a 1-min netting stressor (Pooled diets; n = 12)

Variable	Time after stress (h)a					p valueb
	0	0.5	3.5	9.5	21.5
Glucose (mmol L−1)	3.2 ± 0.1a	5.0 ± 0.2bc	5.6 ± 0.5c	5.9 ± 0.5c	4.4 ± 0.4ab	0.012
pH	7.79 ± 0.01a	7.62 ± 0.03b	8.00 ± 0.03c	7.93 ± 0.01 cd	7.84 ± 0.02ad	0.032
Hct (%)	19.7 ± 0.8ab	23.4 ± 0.9c	20.0 ± 0.7bc	18.1 ± 1.3b	16.7 ± 0.7a	0.399
Lct (%)	1.05 ± 0.09a	1.15 ± 0.10ab	0.83 ± 0.05c	0.77 ± 0.04c	0.99 ± 0.08ac	0.674
TCO2 (mmol L−1)	8.6 ± 0.3a	5.9 ± 0.3b	13.7 ± 1.0c	11.7 ± 0.4 cd	9.9 ± 0.4ad	0.038
HCO3 (mmol L−1)	8.5 ± 0.3a	5.7 ± 0.3b	13.6 ± 1.0c	11.6 ± 0.3 cd	9.8 ± 0.4ad	0.038
BE (mmol L−1)	−12.3 ± 0.4a	−17.3 ± 0.6b	−5.0 ± 1.3c	−8.0 ± 0.5 cd	−10.7 ± 0.6ad	0.028
Cortisol (ng mL−1)	6.4 ± 1.5a	129.2 ± 27.3b	38.5 ± 18.2a	15.0 ± 2.7a	6.2 ± 1.3a	0.014

Hct haematocrit, Lct leucocrit, TCO ₂ total carbon dioxide, HCO ₃ bicarbonate, BE base excess

^aValues within variable followed by different lower case letters differ significantly (p < 0.05)

^b P values for each mean variable of either the SC or WA diet compared with the FM diet based on linear mixed effects models that included diet, time, feed intake and weight as fixed effects and fish and week as random effects