Channel Catfish FCR, Feeding

Rate and Growth

Out of Print

FCR & % Body Weight (BW) consumed for channel catfish (adapted from Robinson et. al. 1998)

Fish Size

(g)

FCR Daily Feed

(% BW)

27.2

45.4

136.2

272.4

340.5

454

908

1362

1.15

1.35

1.50

1.70

1.85

1.95

2.10

2.30

4.25

3.75

2.75

2.25

1.75

1.40

1.15

1.05

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

0 500 1000 1500

y = %BW fed

g

% BW Fed vs. Fish Weight

y = -0.866ln(x) + 7.0132 R² = 0.9755

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

0 500 1000 1500

y= %BW fed

Log. (y= %BW fed)

g

% BW Fed vs. Fish Weight

y = 16x-0.378 R² = 0.9697

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

0 500 1000 1500

Y = % BW

Power (Y = % BW)

g

% BW Fed vs. Fish Weight

% BW fed: reported vs. power & natural log calculated values.

Fish Size

(g)

Reported Power (x) ln (x)

27.2

45.4

136.2

272.4

340.5

454

908

1362

4.25

3.75

2.75

2.25

1.75

1.40

1.15

1.05

4.59

3.78

2.49

1.92

1.76

1.58

1.22

1.04

4.15

3.71

2.76

2.16

1.97

1.72

1.12

0.76

0

0.5

1

1.5

2

2.5

0 500 1000 1500

y = FCR

g

FCR vs. Fish Weight

y = 0.2803ln(x) + 0.2093 R² = 0.9764

0

0.5

1

1.5

2

2.5

0 500 1000 1500

y = FCR

Log. (y = FCR)

g

FCR vs. Fish Weight

y = 0.6742x0.1694 R² = 0.984

0

0.5

1

1.5

2

2.5

0 500 1000 1500

y = FCR

Power (y = FCR)

g

FCR vs. Fish Weight

FCR: reported vs. power & natural log calculated values.

Fish Size

(g)

Reported Power (x) ln (x)

27.2

45.4

136.2

272.4

340.5

454

908

1362

1.15

1.35

1.50

1.70

1.85

1.95

2.10

2.30

1.18

1.29

1.55

1.74

1.81

1.90

2.14

2.28

1.00

1.10

1.41

1.60

1.66

1.74

1.94

2.05

Feeding Rate

• Feed as a percent of body weight (BW)

• 1-5% daily, convert to decimal

• 3% BW = 0.03 x 100 g = 3g/day

Food Conversion Ratio

• FCR = feed fed/weight gained

• Weight gained = feed fed/FCR

%BW = 16W-0.378 %BW = -0.866ln(x) + 7.0132 where %BW = % body weight fed daily & W = weight

FCR = 0.6742W0.1694 FCR = 0.2803ln(x) + 0.0293 where FCR = food conversion ratio & W = weight

Power & ln Equations: %BW & FCR

1993 Field Data (Wurts & Wynne, 1995)

• Stocked 3720, 45-g fingerlings/ha

• Assumed exponential growth up to 227 g – feeding table

• Fed 3% BW: 45 g to 227 g

• Capped feeding @ 34 kg/ha

• Harvest weight 590 g (175 days)

0

100

200

300

400

500

600

700

800

0 50 100 150 200 250

pwr & pwr

ln & ln

ln & pwr

days

g

Plots of Calculated Weight vs. Time

Field vs. Calculated Weight

• 45 g to 590 g in 175 days: FCR 1.7-2 (Wurts & Wynne, 1995)

• 45 g to 512, 568 or 645 g in 175 days (calculated, 2014)

y = 0.0076x2 + 1.0747x + 26.135 R² = 1

0

100

200

300

400

500

600

0 100 200 300 days

g

(power %BW + power FCR)

Growth: Weight vs. Time

y = 0.0104x2 + 1.3449x + 22.562 R² = 0.9998

0

100

200

300

400

500

600

700

800

0 100 200 300

(ln %BW + ln FCR) g

days

Growth: Weight vs. Time

g

y = 0.0094x2 + 1.0443x + 23.904 R² = 0.9999

0

100

200

300

400

500

600

700

0 100 200 300

(ln % BW & Power FCR)

g

days

Growth: Weight vs. Time

So What?

• Improve feeding efficiency

• Improve growth & survival

• Improve FCR

• Increase profit…

References

• Robinson et. al. 1998. Southern Regional Aquaculture Center (SRAC), Publication No. 181 (Out of Print).

• Wurts & Wynne. 1995. World Aq. 26(3): 54-59.

William A. Wurts, Ph.D.

Extension Aquaculture Specialist

College of Agriculture, Food Science & Sustainable Systems

Online Literature & Slide Shows

www.ca.uky.edu/wkrec/Wurtspage.htm