Treatments

Parameter

Shrimp pond

NF

FF

FF+NF

FF+NF+S

Mean final weight (g)

7.87 ± 0.29b

3.99 ± 1.8a

7.66 ± 0.7b

9.47 ± 1.0c

8.72 ± 0.31b,c

SGR

3.5-3.8(3.7)

1-3(2)

3.2-4(3.7)

4-4.7(4.4)

3.9-4.2(4.1)

Survival rate (%)

80 ± 5

85 ± 3

87 ± 3

90 ± 2

97 ± 1

FCR

1.1-1.3

1.3-1.7

0.6-1.3

0.6-1.4

k (d-1)

0.04 ± 0.01b

0.019 ± 0.01a

0.04 ± 0.01b

0.044 ± 0.01b

0.041 ± 0.01b

m (d-1)

0.18 ± 0.01b

0.075 ± 0.04a

0.17 ± 0.03b

0.24 ± 0.04c

0.21 ± 0.01b,c

t50  (d)

2.8-3.6(3.1)

8.1-15(11)

2.5-4(3.3)

1.2-3.7(2.4)

2.4-3.1(2.7)

δ15N(‰)

7.71 ± 0.42

8.82 ± 0.30

8.36 ± 0.39

8.23 ± 0.38

8.01 ± 0.26

δ15Ng (‰)

7.70 ± 0.46

10.95 ± 1.2

8.73 ± 0.43

8.44 ± 0.38

8.15 ± 0.27

Relative contribution (%)

7-32(16)

100

5-29(10)

16-38(18)

Different superscripts indicate significant differences (a<b<c).
Table 5: 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 medium (initial weight, 2.79 ± 0.26 g, δ15N=7.72 ± 0.3‰) L. vannamei reared for 28-days with formulated feed (FF, Pellet 35), natural feed (NF) and 50:50 formulated+natural feeds as plankton+biofloc (δ15NNF=6.7 ± 0.83‰) (FF+NF) and plankton+bioflocs+benthos (δ15NNF=7.54 ± 0.83‰) (FF+NF+S) (Trial 3). Relative contribution of natural diet to the growth of specimens reared on FF+NF and FF+NF+S treatments. Isotopic trophic enrichment (Δ15N=δ15Nshrimp–δ15NNF or FF) was estimated in 2.12‰ for NF and 2.56‰ for FF.
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