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

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MEASURING FEED INTAKE FOR CHANNEL CATFISH Ictalurus punctatus DURING COOL
WEATHER
Adam S. Nanninga and Carole Engle
Mail Slot 4912
University of Arkansas at Pine Bluff
1200 North University Drive
Pine Bluff, AR 71601 USA
ananninga@uaex.edu
Channel catfish Ictalurus punctatus fed based on standard winter feeding recommendations lost weight during winter feeding
studies conducted at the University of Arkansas at Pine Bluff. The objective of this study was to quantify feed consumption
by channel catfish over the winter months. Six concrete vats with a volume of 5 m 3 were stocked in mid October 2007 with 17
sub-market size fish (mean weight 0.25 kg; range of 0.11 to 0.39 kg) and 20 market size fish (mean weight 0.72 kg; range of
0.54 to 1.0 kg). Water was supplied by a pump on the bottom of an adjacent pond at 10.6 l/min. Feed (32% protein full-sink
pellet) was offered daily in feeding trays at a weight of 2% of total body weight of fish every afternoon. After 15 minutes, trays
were pulled up and remaining pellets were counted. All vats were harvested on 16 March 2008.
Channel catfish consumed from 0.1% to 0.7% of their body weight daily over the winter when offered feed every day. While
catfish ate more at higher water temperatures, they continued to eat at temperatures as low as 7 C. Compared with standard
winter feeding recommendations, daily feed consumed by catfish was slightly (0.2 - 0.3%) less than the recommended daily
percent of body weight to feed (at temperatures ≥ 10 C). However, the recommended frequency of feeding resulted in weekly
recommended feed quantities that were 1.3% - 1.6% lower than actual quantities of feed consumed by catfish. Additional work
is needed to refine feeding recommendations for cool-weather feeding, with particular attention to increasing the frequency of
feeding over the winter.
TABLE 1. Feed consumption by channel catfish during cool weather as compared
to standard winter feeding recommendations.
Standard Feeding Measured Feed
Temperature Range (C)
≤ 10 C
Recommendations Consumption
% body weight daily
0%
0.1%
% body weight weekly
> 10 – 15.6 C
0%
0.6%
% body weight daily
0.5%
% body weight weekly
0.5% a
0.3%
15.7 – 21.1 C
1.8%
% body weight daily
1%
% body weight weekly
3% b
0.7%
a
Feed only once a week.
b
Feed every other day.
4.6%