Table 3.
Growth performance, head kidney and spleen weight, index of grown-up grass carp (Ctenopharyn-godon idellus) fed diets containing graded levels of lysine for 60 d.
Item | Dietary lysine level, g/kg diet |
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---|---|---|---|---|---|---|
5.6 | 8.5 | 11.6 | 14.4 | 17.5 | 20.7 | |
IBW1, g/fish | 164.33 ± 0.33a | 164.89 ± 1.07a | 165.00 ± 0.88a | 165.44 ± 0.38a | 164.89 ± 1.02a | 164.56 ± 1.02a |
FBW1, g/fish | 403.33 ± 3.53a | 485.33 ± 3.72c | 581.33 ± 4.00f | 549.78 ± 13.23e | 515.33 ± 5.92d | 442.22 ± 10.12b |
PWG1, % | 144.20 ± 2.11a | 192.62 ± 3.36c | 250.01 ± 2.80f | 230.21 ± 8.24e | 210.59 ± 4.13d | 167.22 ± 5.56b |
SGR1, %/d | 1.49 ± 0.01a | 1.79 ± 0.02c | 2.09 ± 0.01f | 1.99 ± 0.04e | 1.89 ± 0.02d | 1.64 ± 0.03b |
FI1, g/fish | 454.47 ± 0.30a | 527.02 ± 0.28c | 606.50 ± 0.25f | 579.18 ± 0.30e | 541.55 ± 0.26d | 471.06 ± 0.30b |
FE1, % | 0.52 ± 0.01a | 0.61 ± 0.01b | 0.68 ± 0.01d | 0.66 ± 0.02cd | 0.65 ± 0.01c | 0.59 ± 0.02b |
HKW2, g | 0.71 ± 0.01a | 0.96 ± 0.05b | 1.29 ± 0.06d | 1.23 ± 0.02d | 1.05 ± 0.04c | 0.88 ± 0.06b |
HKI2, % | 0.18 ± 0.00a | 0.20 ± 0.01ab | 0.22 ± 0.02cd | 0.23 ± 0.00d | 0.21 ± 0.01bc | 0.20 ± 0.01ab |
SW2, g | 0.55 ± 0.03a | 0.80 ± 0.03b | 1.00 ± 0.02c | 0.99 ± 0.08c | 0.82 ± 0.03b | 0.63 ± 0.01a |
SI2, % | 0.14 ± 0.01a | 0.17 ± 0.01cd | 0.17 ± 0.02cd | 0.18 ± 0.01d | 0.16 ± 0.00bc | 0.14 ± 0.00ab |
Regressions | ||||||
YPWG = −1.495X2 + 40.617X – 36.919 | R2 = 0.970 | P < 0.05 | ||||
YSGR = −0.008X2 + 0.231X + 0.463 | R2 = 0.956 | P < 0.01 | ||||
YFE = −0.211X2 + 5.916X + 26.061 | R2 = 0.957 | P < 0.01 | ||||
YHKI = -0.001X2 + 0.018X + 0.096 | R2 = 0.909 | P < 0.05 | ||||
YSI = −0.001X2 + 0.019X + 0.055 | R2 = 0.933 | P < 0.05 |
IBW = Initial body weight; FBW = final body weight; PWG = percent weight gain; SGR = specific growth rate; FI = feed intake; FE = feed efficiency; HKW = head kidney weight; HKI = head kidney index; SW = spleen weight; SI = spleen index.
a to f Values with different letter superscripts are significantly different (P < 0.05).
Values are means ± SD for 3 replicate groups, with 30 fish in each group.
Values are means ± SD (n = 12).