Table 4.

Growth performance, feed utilization, and survival of juvenile Atlantic bluefin tuna (Thunnus thynnus) fed reference and test diets

Trial A
Dietary treatments
Parameter measured	MGK	15KO	20KO
Initial wet weight (g)	2.9 ± 0.9	2.9 ± 0.9	2.9 ± 0.9
Final wet weight (g)	8.4 ± 0.3a	8.0 ± 0.2b	6.0 ± 0.3c
Initial fork length (cm)	6.5 ± 0.7	6.5 ± 0.7	6.5 ± 0.7
Final fork length (cm)	8.5 ± 0.1a	8.5 ± 0.1a	8.1 ± 0.1b
Weight gain (%)	188.4 ± 16.3a	177.1 ± 13.6b	107.5 ± 8.8c
Specific growth rate (SGR %·day−1)	19.4 ± 0.4a	19.0 ± 0.2b	15.5 ± 0.5c
Condition factor (CF g/cm3)	1.3 ± 0.1a	1.3 ± 0.1a	1.1 ± 0.1b
Feed conversion ratio (FCR)	0.8 ± 0.0	1.0 ± 0.0	0.9 ± 0.1
Daily feeding rate (DFR %)	6.5 ± 0.5	7.3 ± 0.7	8.4 ± 0.5
Survival (%)	25.0 ± 10.6	35.6 ± 11.5	15.0 ± 0.1
Trial B
Dietary treatments
Parameter measured	MGK	15KO	15KORO
Initial wet weight (g)	3.3 ± 0.6	3.3 ± 0.6	3.3 ± 0.6
Final wet weight (g)	10.4 ± 0.3b	11.3 ± 0.1a	11.2 ± 0.1a
Initial fork length (cm)	6.7 ± 0.4	6.7 ± 0.4	6.7 ± 0.4
Final fork length (cm)	9.1 ± 0.1b	9.4 ± 0.1a	9.4 ± 0.1a
Weight gain (%)	216.1 ± 16.4b	243.5 ± 8.2a	242.2 ± 19.6a
Specific growth rate (SGR %·day−1)	22.1 ± 0.2b	22.9 ± 0.1a	23.0 ± 0.2a
Condition factor (CF g/cm3)	1.4 ± 0.1a	1.4 ± 0.1a	1.3 ± 0.1b
Feed conversion ratio (FCR)	1.0 ± 0.0	1.0 ± 0.0	1.1 ± 0.2
Daily feeding rate (DFR %)	6.0 ± 0.5	6.3 ± 0.3	6.7 ± 0.3
Survival (%)	23.8 ± 6.1	26.8 ± 1.0	25.0 ± 4.6

Results are mean ± SD (n = 2, with 20 animals measured per replicate). An SD of 0.0 implies an SD of < 0.05. Values bearing different superscript letters are significantly different (P < 0.05)

MGK reference diet (Magokoro®, Marubeni Nisshin Feed Co., Japan), 15KO diet containing 15% total lipid as krill oil, 20KO diet containing 20% total lipid as krill oil, 15KORO diet containing 15% total lipid as 50% krill oil and 50% rapeseed oil