Parameter

Shrimp pond

NF

FF

FF+NF

FF+NF+S

Mean final weight (g)

17.60 ± 0.23a

17.34 ± 1.32a

17.19 ± 0.23a

18.1 ± 0.84a

SGR

1.8-3.9(3.0)

2.0-4.1(2.7)

2.0-3.2(2.9)

2.0-4.1(3.1)

Survival rate (%)

74 ± 2a

93 ± 3c

87 ± 5b

90 ± 3b,c

FCR

1.1-1.3

1.3-1.7

0.7-1.3

0.8-1.4

k (d-1)

0.030 ± 0.00a

0.029 ± 0.01a

0.03 ± 0.00a

0.031 ± 0.01a

m(d-1)

0.325 ± 0.01a

0.318 ± 0.04a

0.314 ± 0.01a

0.34 ± 0.02a

t50  (d)

1.9-2.2(2.0)

1.8-2.3(2.0)

1.7-2.7(2.0)

1.8-2.0(1.9)

δ15N(‰)

8.42 ± 0.30

8.23 ± 0.17

7.91 ± 0.45

7.61 ± 0.81

δ15N(‰)

8.81 ± 0.33

8.52 ± 0.19

8.02 ± 0.50

7.56 ± 0.87

Relative contribution (%)

0

<10

9-16(13)

Different superscripts indicate significant differences (a<b<c).
Table 6: Mean final weight, specific growth rate (SGR) and growth parameters (m and k), survival, feed conversion ration (FCR), natural stable isotope value (δ15N) and estimated N half time (t50) in tissue of large (initial weight, 6.21 ± 0.72 g, δ15N=6.95 ± 0.34‰) L. vannamei reared for 35-days with formulated feed (FF, δ15N=5.8‰), natural feed (NF) and 50:50 formulated+natural feeds as plankton+bioflocs (FF, δ15NNF=6.7 ± 0.83‰) (FF+NF) and plankton+bioflocs+benthos (δ15N=6.81 ± 0.53‰) (FF+NF+S) (Trial 4). Relative contribution of natural diet to the growth of specimens reared on FF+NF and FF+NF+S treatments. Isotopic trophic enrichment (Δ15N=δ15Nshrimp–δ15NFF) was estimated in 2.43‰ only for FF.
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