Daniel F. Oberle

Use of Corn Gluten Feed and Cottonseed Meal to Replace Soybean Meal and Corn in Diets for Pond-Raised Channel Catfish

Abstract The prices of soybean meal and corn—the two most commonly used, traditional feed ingredients in channel catfish diets—have 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 growin...

Effects of Maintenance Feeding Regimens on Weight Gain, Feed Efficiency, and Body Condition of Pond-Raised Channel Catfish

Abstract This study evaluated the effects of initial fish size and weekly feeding frequency during the growing season on production characteristics and body condition of pond-raised channel catfish Ictalurus punctatus. Two sizes of channel catfish (averaging 39 or 249 g/fish) were stocked into eighteen 0.04-ha ponds at a density of 14,820 fish/ha. On days fed fish were fed to apparent satiation with a commercial 28% protein diet for 15 weeks. Fish fed once weekly to satiation gained 92% or 39% of initial weight for small and large fish, respectively. Maintenance feeding frequency (satiation) for these sizes of fish stocked at 14,820 fish/ha would be less frequent than once weekly. The condition factor improved as weekly feeding frequency increased. Larger fish had a better survival than smaller fish. However, fish survival was not affected by weekly feeding frequency. Based on results from the present study, it appears that feeding once weekly to satiation can maintain the body weight of advanced fingerli...

Effects of Daily Feeding Time and Frequency on Channel Catfish, Ictalurus punctatus Production in Earthen Ponds

Abstract A pond study was conducted to evaluate effects of daily feeding time and frequency on channel catfish, Ictalurus punctatusproduction, feed efficiency, processing yield, and body composition. Channel catfish fingerlings (initial weight = 22 g/fish) were stocked into eighteen, 0.4-ha ponds at a rate of 24,700 fish/ha. The fish were fed to apparent satiation with a commercial 28% protein diet once daily in the morning or afternoon, or twice daily in both morning and afternoon for two growing seasons. On average, fish on the twice-a-day feeding regime were fed about 2,000 kg/ha more diet than fish fed once daily, but due to the large variation in diet input among ponds there were no significant differences in the amount of diet fed among treatments. No differences were observed in weight gain per fish, estimated survival, net production, visceral fat, or fillet proximate composition among treatments. Feed conversion ratio decreased in fish fed once daily in the morning compared to fish fed once daily in the afternoon or twice daily. Fish fed twice daily had higher carcass and fillet yields than fish fed once daily in the afternoon. However, whether the differences in feed conversion ratio and processing yield are true biological responses needs further investigation. Results from this study indicate that there are few, if any, advantages in feeding food-sized channel catfish twice daily or at a certain time of day. Therefore, we recommend that food-fish in grow-out ponds be fed once daily to apparent satiation but not exceeding what an individual pond can “metabolize,” and feeding should begin early in the morning as soon as dissolved oxygen levels begin to increase.

Effects of Dietary Fiber Concentrations Supplied by Corn Bran on Feed Intake, Growth, and Feed Efficiency of Channel Catfish

Abstract The present study examined the effects of dietary fiber and digestible energy on the feed intake, growth, and feed efficiency of juvenile channel catfish Ictalurus punctatus. Fish with an initial weight of 9.8 ± 0.1 g/fish (mean ± SD) were stocked in 110-L flow-through aquariums and fed for 9 weeks with practical diets that contained graded levels of fiber supplied by corn bran. As total dietary fiber (TDF) increased, feed consumption and weight gain increased and then decreased, showing a quadratic response. Maximum feed consumption occurred at a TDF level of 27.0% (5.7% crude fiber, 19.1% neutral detergent fiber [NDF]). Channel catfish appear to have some ability to adapt to increased dietary fiber by increasing feed intake to satisfy their energy requirements. Maximum weight gain was achieved at a TDF level of 23.4% (5.0% crude fiber, 15.7% NDF), indicating that the presence of dietary fiber at certain levels is beneficial to the fish. The maximum tolerance level for TDF by channel catfish was...

Effects of Feeding Rate and Frequency on Production Characteristics of Pond-Raised Hybrid Catfish

Abstract The present study examined the effects of various daily feeding rates and feeding every other day on the growth, net yield, feed conversion ratio, and size distribution of hybrid catfish (female channel catfish Ictalurus punctatus × male blue catfish I. furcatus) in production ponds. Hybrid catfish fingerlings (average size, 45 g) were stocked into 0.04-ha ponds at a density of 14,826 fish/ha. Initially, all fish were fed to apparent satiation until feed consumption reached predetermined levels. Thereafter, the daily feeding rates for fish in the restricted feeding group were no more than 112, 135, or 168 kg·ha−1·d−1. Fish in the every-other-day feeding group were fed to apparent satiation daily until they reached about 0.23 kg and every other day to satiation thereafter. The results from the present study show that feeding every other day significantly reduces the weight gain and net yield of hybrid catfish but improves the feed conversion ratio. Partial budget analysis indicates that feeding hy...

Evaluation of Various Feeding Regimens in a Multiple-Batch Cropping System of Channel Catfish Production

Abstract A 4-year pond study was conducted to compare net production, feed conversion, processing yield, and body composition of channel catfish Ictalurus punctatus that were fed once daily, fed every other day (EOD) to satiation, or fed an amount not exceeding 110 kg·ha−1·d−1 in a multiple-batch cropping system. The greatest amount of feed administered was observed for the daily satiation group, followed by the 110-kg·ha−1·d−1 group and the EOD group (P ≤ 0.05). Net production of fish fed daily to satiation did not significantly differ from that of fish fed up to 110 kg·ha−1·d−1, but that of fish fed daily (satiation or ≤110 kg/ha) was significantly higher than that of fish fed EOD to satiation. Feed conversion ratio was significantly lower in fish fed up to 110 kg·ha−1·d−1 or EOD to satiation than that of fish fed daily to satiation. Carcass, fillet, and total meat yields did not differ among feeding regimens. Fish fed EOD to satiation had lower fillet fat and higher fillet moisture than fish fed daily ...

Evaluation of Hydrolyzed Poultry Feathers as a Dietary Ingredient for Pond-Raised Channel Catfish

Abstract The present study examined the use of hydrolyzed poultry feathers (HPF) as a replacement for soybean meal in diets for pond raised Channel Catfish Ictalurus punctatus. Four isonitrogenous (28% crude protein) diets were evaluated that contained 0, 5, 10, or 15% HPF. Fingerling Channel Catfish (mean ± SD initial weight was 47.5 ± 2.2 g) were stocked into twenty 0.04-ha earthen ponds at a rate of 14,830 fish/ha. Fish were fed once daily to apparent satiation for 140 d. No significant differences were observed for weight gain, feed conversion ratio (FCR), and survival among fish fed various levels of HPF. There were also no significant differences in net yield of fish fed diets containing 0, 5, and 10% HPF, but net yield of fish fed a diet containing 15% HPF was significantly lower than that of fish fed the control diet. Fish on diets containing 5% HPF and above were fed significantly less feed than fish fed the control diet. Regression analysis showed that total amount of diet fed, net yield, and we...

Can Reduced Stocking Rates and Bug Lights Produce Market-Sized Catfish From Fingerlings in One Growing Season?

The purpose of this study was to determine the feasibility of growing marketable channel catfish, Ictalurus punctatus, from pond-run fingerlings (15.9 g/fish) using low stocking densities (7,413 or 14,826 fish/ha) and electrified bug lights to enhance natural forage available to fish. Even at low stocking densities, fish only averaged 0.2 kg at the end of the growing season. Because marketable sizes of fish were not reached over the growing season, stocking small fingerlings at these rates would not be practical under most commercial production scenarios. Nutritionally, captured insects from electrified bug lights were near a complete diet for catfish, but bug lights did not capture sufficient quantities of insects to affect fish production in either stocking density. Stocking small fingerlings at low stocking rates does not produce market‐sized catfish during one growing season; commercially available bug lights did not provide adequate amounts of natural forage to affect production variables.

Proximate Composition and Collagen Concentration of Processing Residue of Channel Catfish

Abstract Residues—including heads, skin, viscera, frames, and trimmings—from the channel catfish Ictalurus punctatus processing industry have generally been made into catfish meal and catfish oil that are used in animal feeds. There may be more efficient uses for these materials, such as producing collagen and other products. A study was conducted to determine the percentages of each component of the processing residue relative to whole fish weight and their crude protein, crude fat, moisture, ash, and collagen concentrations. Of a market-size channel catfish, the head accounted for 24% of the whole weight, the frame 13.6%, the viscera 10.8%, the skin 4.7%, and the trimmings 3.7%. These processing residues represent a total of 56.8% of the total fish weight. The highest crude protein and collagen concentrations were found in the skin (protein, 19.9% of wet tissue and 82.1% of dry matter; collagen, 14.2% of wet tissue and 58.7% of dry matter). The viscera had the highest fat level (32.7% of wet tissue and ...

Efficacy of High-Protein “Finishing” Diets on Growth, Fattiness, and Processing Yield of Channel Catfish, Ictalurus punctatus

Abstract Three experiments were conducted to evaluate the use of “finishing” diets in channel catfish, Ictalurus punctatusproduction. Fingerling channel catfish weighing 107, 129, and 103 g for Experiments 1, 2, and 3, respectively, were stocked in 0.04-ha earthen ponds at a rate of 14,820 fish per ha and grown to harvestable size in a single growing season. Four replicate ponds were used for each treatment. In Experiment 1, fish were fed either a 28%- or 32%-protein diet for the entire growing season (controls), or fed the 28%- and 32%-protein diets for part of the growing season and then switched to a 36%-protein “finishing” diet either 30 days or 60 days before harvest. In Experiment 2, fish were fed either a 24%- or 32%-protein diet for the entire growing season (controls), or fed a 24%-protein diet for part of the growing season and then switched to a 32%- or a 35%-protein “finishing” diet for either 30 days or 45 days before harvest. In Experiment 3, fish were fed either a 28%-protein diet for the entire growing season or a 28%-protein diet for part of the growing season, and then switched to a 35%-protein “finishing” diet for either 30, 45, or 60 days before harvest. The data show that a 24%-protein diet is sufficient for maximum growth and feed efficiency of catfish but processing yield is reduced. Further, it appears that feeding fish a 24%-protein diet for most of the growing season and then changing to a 32%- or 35%-protein “finishing” diet for 30 days before harvest, improves carcass yield. Fillet yield also appeared to be improved, but the improvement was slight. The data did not show that “finishing” fish fed a 28%-protein diet on higher protein diets was beneficial in improving processing yield. However, evaluating pooled data from across all of our previous studies, there does appear to be about a 0.4% to 0.5% decrease in processing yield of fish fed a 28%-protein diet. Presently, we do not recommend the use of “finishing” diets, because available data are not consistent, and their benefit is questionable. Also, because of various factors (such as off flavor), one cannot predict with certainty when fish will be harvested.