Table 1: Mean (SE) growth and condition values for Rainbow Trout that survived for 90 days after undergoing one of three treatments: anesthesia (handled, N= 26), anesthesia and sham surgery (sham, N = 24), and anesthesia and implantation of an inert acoustic transmitter (tagged, N = 18). For each variable, values within a row with different letters are significantly different (P < 0.05).

Handled Sham Tagged
Final length (mm) 343 (6) 352 (5) 326 (7)
Final weight (g) 537 (36) zy 584 (28) z 473 (41) y
Condition factor a 0.128 (0.003) 0.132 (0.003) 0.131 (0.002)
Weight gain (g) 344 (29) z 343 (22) z 243 (30) y
Percent weight gain (%) 182 (13) z 150 (10) z 108 (12) y
Length increase (mm) 71 (3) z 62 (5) z 45 (6) y
Percent length increase (%) 26.3 (1.3) z 21.8 (2.0) zy 16.2 (2.1) y
Specific growth rateb 0.487 (0.022) z 0.431 (0.022) z 0.340 (0.028) y
HSI c 1.83 (0.09) 1.88 (0.15) 1.87 (0.09)
VSI d 14.55 (0.49) 15.53 (0.62) 14.36 (0.72)
SSI e 0.19 (0.01) zy 0.17 (0.01) z 0.24 (0.02) y
Mortality 4 6 12

a Condition factor (K) = [weight (g) / length (cm)3] x 100
b Specific growth rate (SGR) = [(Log final weight - Log initial weight) / time interval] x 100
cViscerosomatic index (VSI) = [(weight of viscera ÷ total fish weight) x 100]
dHepatosomatic index (HSI) = [(liver weight ÷ total fish weight) x 100]
eSplenosomatic Index (SSI)= [(spleen weight ÷ total fish weight) x 100]

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