Table 2.

Survival and growth performance and feed utilization of coho salmon Oncorhynchus kisutch (Walbaum, 1792) postsmolts fed the experimental diets with different vitamin C (VC) levels for 10 weeks¹.

Dietary VC levels (mg/kg)	1.8	10.9	50.8	100.5	197.3	293.8	586.7	Regression analysis2
								Linear	Quadratic	Cubic
SR (%)	93.33 ± 3.33	96.67 ± 3.33	96.67 ± 3.33	100	100	100	93.33 ± 6.67	0.58	0.09	0.43
IBW (g)	181.00 ± 1.00	182.33 ± 1.20	183.33 ± 0.67	184.33 ± 1.20	183.33 ± 0.88	184.33 ± 1.20	183.67 ± 1.20	0.35	0.18	0.80
FBW (g)	383.68 ± 2.70a	386.87 ± 1.32a	425.56 ± 6.71c	441.46 ± 2.95d	454.35 ± 3.95d	443.49 ± 2.58d	407.13 ± 9.22b	<0.01	<0.01	<0.01
SGR (%/day)	1.073 ± 0.002a	1.075 ± 0.014a	1.203 ± 0.025c	1.248 ± 0.017cd	1.297 ± 0.006d	1.254 ± 0.010cd	1.137 ± 0.024b	<0.01	<0.01	<0.01
FCR	2.501 ± 0.008d	2.497 ± 0.079d	2.123 ± 0.067b	2.009 ± 0.041ab	1.894 ± 0.014a	1.992 ± 0.023ab	2.307 ± 0.073c	<0.01	<0.01	<0.01
CF (g/cm3)	1.270 ± 0.162	1.111 ± 0.059	1.228 ± 0.008	1.272 ± 0.168	1.193 ± 0.043	1.409 ± 0.059	1.204 ± 0.062	0.496	0.983	0.192
HSI (%)	0.661 ± 0.061	0.750 ± 0.081	0.604 ± 0.016	0.656 ± 0.035	0.668 ± 0.029	0.714 ± 0.006	0.713 ± 0.028	0.530	0.299	0.825
ISI (%)	5.160 ± 0.633	5.294 ± 0.670	4.606 ± 0.431	4.557 ± 0.455	4.780 ± 0.231	4.933 ± 0.240	5.775 ± 0.120	0.588	0.06	0.471

Abbreviations: SR: survival rate; IBW: initial body weight; FBW: final body weight; FCR: feed conversion ratio; CF: condition factor; HSI: hepatosomatic index; ISI: intestosomatic index. ¹Each value represents the mean of 3 replicates. ²Orthogonal polynomial contrasts were used to assess the significance of linear, quadratic, or cubic models to describe the response in the dependent variable to VC level. A probability value of P < .05 was described to be statistically significant.