Each raceway is monitored with a YSI5200 multiparameter monitoring and control instrument that tracks oxygen and temperature. The YSI5200s activate oxygen blowers as needed; they will soon also be used to automatically deliver feed, adjusting for growing biomass.

1. January | February 2010
Feature title: High-intensity raceway production could put catfish producers in the fast lane
International Aquafeed is published five times a year by Perendale Publishers Ltd of the United Kingdom.
All data is published in good faith, based on information received, and while every care is taken to prevent inaccuracies,
the publishers accept no liability for any errors or omissions or for the consequences of action taken on the basis of
information published.
©Copyright 2009 Perendale Publishers Ltd. All rights reserved. No part of this publication may be reproduced in any form
or by any means without prior permission of the copyright owner. Printed by Perendale Publishers Ltd. ISSN: 1464-0058
The International magazine for the aquaculture feed industry

2. F: Raceway production F: Feature
nutrients from manure and bits of feed, adding raceway, and a seventh 5200
oxygen to the water. monitors the quality of incom- Each raceway is monitored with a YSI
Photo: ©Travis W. Brown
However, notes Brown, pumping solid ing water. 5200 multiparameter monitoring and
manure out of a trough at the end of the If oxygen or temperatures control instrument that tracks oxygen
raceways minimizes nutrient overloading that drift outside of accept- and temperature. The YSI 5200s activate
oxygen blowers as needed; they will soon
can cause boom-and-bust algal blooms. able levels, the instruments call
also be used to automatically deliver
Brown says a bloom heavy enough to Brown’s cell phone with an feed, adjusting for growing biomass
consistently maintain 20 to 30 cm of Secchi alarm message.
disk visibility represents the ideal level of algae A low-oxygen reading will
to manage the system’s water. also activate an emergency blower system as succeed on his farm provides another kind
Beneath the surface, paddlefish graze on necessary. of peace of mind for Wilson – hope that his
zooplankton. Brown points out that he can also set the state’s catfish industry, battered for years by
Tilapia control blue-green algae that can cause instruments to automatically dispense feed high production costs and competition from
off-flavors in the catfish. Fathead minnows eat the in each raceway. YSI software can automati- imports, can prevail through more intensive
flatworms that can cause proliferate gill disease, cally adjust feed timing and quantity based on management.
or ‘hamburger gill’.And red-eared sunfish or ‘shell biomass in the pond. “The future of the catfish industry is in
crackers’ keep mollusks under control. He says he plans to bring the automatic lowering the cost of production,” Wilson says.
feeding capabilities online soon. In the mean- “It always has been, but it’s more critical
High-intensity raceway production Boosting feed efficiency time, the YSI5200s keep constant watch on now.”
Photo: ©Travis W. Brown
Keeping fish in a raceway also makes it water quality.
easier to deliver food to them quickly, effi- “The more intensive the operation, the
could put catfish producers in the fast lane ciently and frequently, notes Professor Jesse
Chappell, who heads up the study.
better management and control you need
to have,” says Tim Grooms, Global Business
More inforMation:
YSI Incorporated
“We’re not trying to feed the same way Development Manager for YSI. 1700/1725 Brannum Lane, Yellow Springs,
by YSI Incorporated Ohio 45387-1107, USA
other growers are feeding,” he says. “If you push the envelope too far, you can
Tel: +1 937 7677241
“We’re feeding multiple times per day, get- create a lot of stress.” Fax: +1 937 7679353
Above: An innovative raceway production system being tested by Auburn University researchers could reduce per-pound ting feed efficiency in line with what the animal Surprisingly, Wilson – whose Dean Wilson
production costs by half while tripling annual yield per acre will do. We try to reduce stress and get the Catfish Farm
animal in the best possible position to obtain encompasses 34
A
the best possible feed efficiency.” ponds – points
n experimental, high- Butch Wilson, president of the Alabama Brown. Instead of running conventional Professor Chappell points out that most out that the
intensity raceway produc- Catfish Producers Association and the pro- paddlewheel aerators that require three Alabama catfish farmers achieve feed conver- raceway system
tion system designed by ducer hosting the research project on his to five horsepower per acre, the Auburn sion ratios (FCR) in the range of 2.8:1 to 3.0:1. was actually
US researchers at Auburn 450-acre (182 hectare) farm near Marion system requires just 0.5 horsepower per His goal through intensive feeding is to his most stable
University could drive Alabama Junction, Ala., says his industry’s future raceway to operate a slow-turning paddle improve FCR to 1.5:1. pond during a
producers’ catfish production costs depends upon cutting per-pound produc- wheel. With today’s feed costs nearly double power failure
– currently well above 70 cents per tion costs and boosting output. “Our paddles are just for current flow, what they were in early 2007, improving this summer.
pound – down to about 50 cents by “If we’re going to compete in a world not for aeration,” Brown says. feed efficiency has a profound impact on the “We had a
improving feed and energy efficiency. market, it’s critical,” he says. “We have a large paddle running at producer’s bottom line. six-hour outage,
1.2rpm to create a constant current through In any fish production system, a significant which was very
Carefully managing fish in tightly populat- Tight fit the raceway, counter-clockwise around the proportion of the nutrient inputs end up as rare,” he recalls.
ed raceways could yield 25,000 to 35,000lbs The high-volume system packs an acre’s pond. We can evacuate the water from the waste. Brown points out that collecting waste “All we did
of catfish per acre per year, more than three worth of fish into each of six concrete raceway every three minutes, and we’re solids in a trough at the end of the raceways in that pond was
times the state’s average of 8000lbs per raceways that are 32 feet long, 16 feet wide trying to keep the entire quantity of water will allow high-intensity producers to recapture stick in a tractor
acre per annum. and 4 feet deep (9.75 meters by 4.9 meters thoroughly mixed to prevent stratification some of their feed investment. with a port-
“The main goal of the system is to by 1.2 meters). during the summer months.” “Only 30 to 35 percent of the nutrients able aerator.That
produce a high volume of fish in a small area The raceways are arrayed side-by-side in in the feed are utilized in fish growth and pond never got
with minimal energy input and lower pro- a portion of a traditional, six-acre (2.4-hec- Low-pressure blowers maintenance,” he explains. close to killing
duction cost than traditional methods,” says tare) earthen pond. An air diffuser system located at the head “If we can reclaim some of that money by fish. In our other
graduate research assistant Travis Brown, The series of raceways comprises a of each channel is operated by 1.5 horsepower, using the fish waste in a slurry on farmland ponds, we were
who is managing the project as part of his multi-stage system. Though they contain fish low-pressure blowers activated intermit- or as compost, we have made this even more running around,
dissertation through Auburn’s Department of a uniform size and age – minimizing pre- tently by the system’s water quality monitoring profitable.” putting in aera-
of Fisheries and Allied Aquacultures. dation – each is stocked at different times instruments to provide supplemental oxygen in tors to keep fish
Though converting a traditional earthen throughout the year to stagger harvest each raceway as needed. A closer watch alive.”
pond to a raceway system may cost as dates and prevent the pond from carrying As the water travels away from the race- Intensifying production requires more care- A backup
much as US$7000 to US$8000 per acre, a full load of harvest-weight fish in each ways and out into the rest of the pond, it ful scrutiny of conditions in the raceways. generator now
Brown says the reduction in input costs raceway at one time. encounters an array of biological treatments To keep a close watch on temperature and provides peace
associated with increased production, as In addition to concentrating fish in the – a menagerie of aquatic species that keep it dissolved oxygen levels, Brown and Chappell of mind, he adds.
well as the tripling of production, are likely raceways, the system concentrates aeration aerated and clean. placed a YSI5200 multiparameter monitoring Seeing the
to pay off quickly. efforts where the fish are located, notes A stable bloom of algae thrives on dissolved and control instrument at the tail end of each raceway system
34 | InternatIonal AquAFeed | January-February 2011 January-February 2011 | InternatIonal AquAFeed | 35

3. LINKS
This digital re-print is part of the January | February 2010 edition of International Aquafeed magazine.
Content from the magazine is available to view free-of-charge, both as a full online magazine on our
website, and as an archive of individual features on the docstoc website.
Please click here to view our other publications on www.docstoc.com.
Vo l u m e 1 4 I s s u e 1 2 0 1 1
• See the full issue
Mycotoxins in aquafeeds
• Visit the International Aquafeed website
Least cost formulation in
aquafeed
• Contact the International Aquafeed Team
The multi-formulation:
- a key tool for the raw materials purchasing
Bangladesh
Formulation, status and sustainability of
aquaculture feed industries
• Subscribe to International Aquafeed
the international magazine for the aquaculture feed industry
To purchase a paper copy of the magazine, or to subscribe to the paper edition please contact
our Circulation and Subscriptions Manager on the link above.
INFORMATION FOR ADVERTISERS - CLICK HERE
www.aquafeed.co.uk