Location: Warmwater Aquaculture Research UnitTitle: Use of corn gluten feed and cottonseed meal to replace soybean meal in diets for pond raised channel catfish Author
Submitted to: North American Journal of Aquaculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/1/2010
Publication Date: 4/5/2011
Publication URL: http://handle.nal.usda.gov/10113/55540
Citation: Li, M.H., Robinson, E.H., Bosworth, B.G., Oberle, D.F., Lucas, P.M. 2011. Use of corn gluten feed and cottonseed meal to replace soybean meal in diets for pond raised channel catfish. North American Journal of Aquaculture. 73:153-158. Interpretive Summary: Soybean meal and corn are the two most commonly used traditional ingredients in diets of channel catfish. However, prices for these feedstuffs have risen dramatically in the past few years because of government policies on renewable fuels and other economic conditions. Much effort has been given to the exploitation of less-expensive, alternative feed ingredients to replace soybean meal and corn to reduce feed cost in channel catfish. Two feed ingredients of interest are corn gluten feed, a by-product of refining corn by the wet-milling process, and cottonseed meal, a protein source that has been used in catfish feeds, but at low levels. Results demonstrate that a maximum of 50% of the soybean meal in catfish diets may be replaced by a combination of corn gluten feed and cottonseed meal (up to 20% of each in the diet) without markedly affecting the physical quality of feed pellets, fish growth, processed yield, and body composition. At current feed prices, the use of corn gluten feed and cottonseed meal to replace 50% of soybean meal in catfish feeds would substantially reduce feed cost.
Technical Abstract: The prices of soybean meal and corn he two most commonly used, traditional feed ingredients in channel catfish diets ave increased dramatically in recent years. Using less-expensive alternative feed ingredients to partially replace soybean meal and corn would reduce feed cost. The present study evaluated the use of corn gluten feed and cottonseed meal, two promising alternative feedstuffs, as replacements for soybean meal and corn in diets for pond-raised channel catfish Ictalurus punctatus. Five isonitrogenous (28% crude protein) diets that used corn gluten feed and cottonseed meal (approximately 1:1 ratio) to replace 0, 25, 50, 75, or 100% of the soybean meal in the control diet were evaluated. The level of corn in the diet decreased as those of corn gluten feed and cottonseed meal increased. Stocker-size channel catfish (mean initial weight = 0.175 kg/fish) were stocked into twenty 0.05-ha earthen ponds at a rate of 14,830 fish/ha. Fish were fed once daily to apparent satiation over a growing season. Net yield, carcass and fillet yield, and fillet protein and fat levels decreased and the feed conversion ratio increased linearly as soybean meal replacement levels increased. These results demonstrate that a maximum of 50% of the soybean meal in channel catfish diets may be replaced (soybean meal was reduced from 51.4% to 25.7%) by a combination of corn gluten feed and cottonseed meal (up to 20% of each in the diet) without markedly affecting the physical quality of feed pellets, fish growth, processed yield, and body composition. The poor performance of diets containing high levels of corn gluten feed and cottonseed meal are probably a result of high fiber, low digestible energy, or both.