February 15-18, 2009 Washington State Convention Center Seattle ...

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EFFECTS OF DIETARY PROTEIN SOURCE AND INTERACTIVE EFFECTS OF PROTEIN
AND LIPID SOURCE ON CHANNEL CATFISH EGG BIOCHEMICAL COMPOSITION, EGG
AND FRY PRODUCTION, AND EGG AND FRY QUALITY
Todd D. Sink* and Rebecca T. Lochmann
University of Arkansas at Pine Bluff
1200 N. University Drive
Pine Bluff, AR 71601 USA
tsink1@uaex.edu
Four diets (36% protein, 10% supplemental lipid) differing in protein source or protein and lipid source were used to examine
the effects of protein source and protein lipid source interactions on egg and fry production in channel catfish. Diets included
(1; control) fish meal, poultry by-product meal, and 10% menhaden fish oil (FM-PBM-FO), (2) fish meal, poultry by-product
meal, 5% menhaden fish oil, and 5% poultry fat (FM-PBM-FO-PF), (3) poultry by-product meal and 10% menhaden fish oil
(PBM-FO), or (4) all plant protein sources and 10% menhaden fish oil (PP-FO). Four-year-old broodfish were stocked at a ratio
of 3 females: 1 male into each of 16 tanks (2.5 m, 2,365 L) in February of 2008 and fed assigned diets up to 5 times weekly
throughout the study dependant upon water temperatures. Spawning cans were placed in the tanks in April and checked three
times weekly through the second week in July.
Twenty-five of 48 possible spawns were collected
(52.1% spawn success). There were no differences
in brood mortality among the diet treatments. Fish
fed the FM-PBM-FO-PF diet had greater spawning
success, fecundity, egg mass weight, and hatch
rates than fish fed PP-FO, but most parameters
were not different from the control or PBM-FO
diet. No significant protein by lipid source interaction
was found for any parameter between the
control and FM-PBM-FO-PF diets, indicating that
poultry fat can be used to partially replace fish oil
in catfish broodstock diets when a variety of animal
and plant protein sources are used. Analysis of
protein source revealed that fish fed diets containing
FM and PBM (in addition to plant proteins)
produced more eggs than fish fed only PBM or PP.
Additional analyses of eggs and fry are ongoing,
but initial data suggests that catfish broodstock
produce more eggs when fed a variety of animal
protein and lipid sources.
Measurement
parameter Diet
FM-PBM-FO FM-PBM-FO-PF PBM-FO PP-FO
Total broodstock
survival (%) 81.3 75.0 81.3 87.5
Female broodstock
survival (%) 66.7 50.0 66.7 83.3
Spawning success
(%) 58.3 a 58.3 a 58.3 a 33.3 b
Fecundity (eggs·kg
female -1) 6,432 a 6,420 a 4,060 a,b 1,072 b
Spawn time (days
post can insertion) 25.3 23.7 31.0 43.0
Water temperature
at spawning (°C) 26.0 26.7 26.2 27.7
Egg mass weight,
matrix intact (kg) 0.722 a,b 0.814 a 0.436 a,b 0.357 b
Total egg volume,
matrix removed
(mL) 847 a,b 1019 a 540 a,b 490 b
Individual egg
weight (g) 0.0298 a,b 0.0338 a 0.0281 b,c 0.0240 c
Eggs·mL -1 23.1 a 21.2 a,b 21.6 a,b 16.3 b
Eggs·spawn -1
(volumetric) 19,654 a,b 21,814 a 11,782 a,b 7,991 b
Eggs·spawn -1
(mass) 20,268 a 19,844 a 11,132 a,b 7,458 b