Progress 10/01/98 to 09/30/05
Outputs
This project consisted of a series of pond production studies combined with economic analyses to identify the optimal stocking size of fingerling to understock in catfish production ponds and to explore production characteristics of producing an intermediate stocker size of catfish. The fingerling production studies resulted in new recommendations for fry stocking densities to produce various sizes of catfish fingerlings. The study also provided the first assessment of the relative economic risk associated with the various stocking densities and management alternatives considered for catfish fingerling production. New feeds, improved aeration are likely responsible for the improved production performance documented in these studies as compared to the previous long-standing recommendations. Moreover, the growout trial showed that the economically optimal size of fingerling to understock in multiple-batch catfish production is a 12.5-cm fingerling. Smaller fingerling
sizes suffered greater mortality and slower growth while larger fingerling sizes competed with the larger, carryover fish. The stocker production studies developed databases of production characteristics of stocking fingerlings at various densities and sizes to produce an intermediate, stocker size of catfish. Recommendations for the optimal density and size of fingerling to use to produce stockers were developed based on growth, yield, and costs per kg and per fish. Mathematical programming models demonstrated that, to incorporate a third, stocker phase of production on a catfish farm, stocking 10-cm fingerlings at 100,000/ha is the most economical alternative. In this alternative, 255-g stokcers are transferred into the growout production phase for subsequent single-batch growout. However, when multiple-batch production alternatives were included in the model, understocking a 37 g fingerling directly into multiple-batch growout was selected most often. Overall, this project has
developed the first set of production data on production of catfish stockers. Switching to a three-phased production system with single-batches of uniform sizes of fish is appealing from a managment perspective and may be a viable option for larger farms at times when the market demands large fish. However, for smaller farms and particularly during times when the market demand is for smaller fish, the traditional multiple-batch system, understocking 12.5-cm fingerlings, may still be the most economical option for catfish farms
Impacts
The new recommendations for fingerling production have been disseminated and are in use. Some larger farms have switched to a three-phased single-batch production system with stockers, but smaller farms have the justification to remain with a multiple-batch system, particularly when markets call for smaller fish.
Publications
- Pomerleau, S. and C.R. Engle. 2005. The effect of on-farm production of various sizes of stocker catfish Ictalurus punctatus on farm profitability. Journal of the World Aquaculture Society 36(3):291-301.
- Pomerleau, S. and C.R. Engle. 2005. An economic comparison of producing catfish, Ictalurus punctatus, stockers with either 9-cm, 11-cm, or 13-cm fingerlings. Journal of Applied Aquaculture 17(2):61-74.
- Engle, C.R. 2004. Fry stocking rates for the production of channel catfish fingerlings. Cooperative Extension Program Fact Sheet FSA 9091, University of Arkansas at Pine Bluff, Pine Bluff, Arkansas.
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Progress 01/01/04 to 12/31/04
Outputs
A two-year catfish farm model was developed using mathematical programming techniques. The LP model focused strictly on the modular catfish production system. The objective function was to maximize expected net returns over a two-year period by selecting the optimal stocker production stragegy subject to pond balance, fish balance, and other production constraints. The model allocated approximately 30% of the farm water-area to stocker production and the remaining 70% to growout. The model selected stocker production from 10-cm finglerings stocked at 100,000/ha because this strategy resulted in the lowest cost/kg of stocker produced because it generated the highest yields (kg/ha). In the model, fingerlings were grown for a year and the resulting stockers were transferred to growout ponds at a size of 255g. Sensitivity analysis indicated that the model was robust to large variations in financial variables. The profit maximizing strategy selected by the model did not
significantly change with variations in harvest costs from 0-200% of baseline, foodfish prices from $1.10 to $1.76/kg, fingerling prices from 50 to 150% of baseline, feed price from $225 to $300/metric ton, feed conversion ratios from 1.5 to 3.0, or mortality rates from 0 to 0.33%/day.
Impacts
There is a great deal of interest in a three-phased catfish production strategy.. This analysis indicates the trade-offs among size of fingerling stocked, yield, net returns, and risk to provide a basis of information for farm decision making.
Publications
- Pomerleau, S. and C.R. Engle. 2005. An economic comparison of producing catfish, (Ictalurus punctatus), stockers with either 9-, 11-, or 13-cm fingerlings. Journal of Applied Aquaculture.
- Pomerleau, S. and C.R. Engle. 2003. Production of stocker-size channel catfish: effect of stocking density on production characteristics, costs, and economic risk. North American Journal of Aquaculture 65:112-119.
- Engle, C.R. and D. Valderrama. 2002. Production characteristics, costs and risk of producing channel catfish, (Ictalurus punctatus), fingerlings on farms with thinning. Journal of Applied Aquaculture 12(2):51-64.
- Engle, C.R. and D. Valderrama. 2001. Effect of stocking density on production characteristics, costs and risk of producing fingerling catfish. North American Journal of Aquaculture 63(3):201-207.
- Engle, C.R. 2001. The economics of producing and understocking different sizes of catfish fingerlings on growout farms. Cooperative Extension Program ETB255, University of Arkansas at Pine Bluff, Pine Bluff, Arkansas.
- Pomerleau, S. and C.R. Engle. 2004. Linear programming analysis of optimal production strategies for catfish (Ictalurus punctatus) farms. Abstract. Aquaculture 2004. Annual Meeting of the World Aquaculture Society, Honolulu, Hawaii.
- Pomerleau, S. and C. Engle. 2004. Stocker catfish production: a summary. Poster abstract. Aquaculture/Fisheries Center of Excellence Field Day, University of Arkansas at Pine Bluff, Pine Bluff, Arkansas.
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Progress 01/01/03 to 12/31/03
Outputs
Vat-graded channel catfish fingerlings averaging (+SD) 9.3 + 0.7 cm (6.8 g), 11.2 +0.9 cm (11.1 g), and 13.2 + 1.3 cm (21.7 g) were stocked into nine 0.04-ha earthen ponds at 100,000 fingerlings/ha. Fish were fed once daily to apparent satiation with 32% protein extruded commercial floating catfish pellets. Enterprise budgeting techniques were used to compare costs of producing catfish stockers on farm from 9, 11, and 13-cm fingerlings. A stochastic Monte Carlo simulation model was used to measure effects of stochastic fluctuations on break-even costs, and to compare risk of on farm stocker production costs exceeding market prices. Stocking larger fingerling significantly (P<0.05) increased total yield, net yield, final weight, final length, and FCR. Total yield increased from 3,150 +183 kg/ha for the 9-cm fingerling treatment to 6,114 +585 kg/ha for the 13-cm fingerling treatment. Tightly grading fingerlings at stocking resulted in detection of significant
differences in stocker yields, FCR, mean harvest weight, and mean harvest length. Total operating costs increased with the size of fingerling at stocking because fingerling, feed, harvest, and interest costs increased. Reverse cumulative distribution functions for each treatment showed that the risk of breakeven cost exceeding specified market prices decreased as the size of fingerling stocked increased. Results suggested that as the size of fingerling stocked in ponds to produce stockers increases from 9 to 13 cm, yield and net returns increase, while the cost/kg of stocker produced and risk decrease.
Impacts
There is a great deal of interest in a three-phased catfish production strategy.. This analysis indicates the trade-offs among size of fingerling stocked, yield, net returns, and risk to provide a basis of information for farm decision making.
Publications
- Pomerleau, S. and C. Engle. 2003. Economic effect of stocker catfish (Ictalurus punctatus) production on farm profitability. Abstract. Aquaculture America 2003, Louisville, Kentucky.
- Pomerleau, S. and C. Engle. 2003. Economic effect of stocker catfish (Ictalurus punctatus) production on farm profitability. Abstract. Annual Meeting of the Arkansas Chapter of the American Fisheries Society, Jackson, Tennessee.
- Pomerleau, S. and C. Engle. 2003. Economic effect of stocker catfish production on farm profitability. Abstract. Catfish Farmers of America Research Symposium, San Destin, Florida.
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Progress 01/01/02 to 12/31/02
Outputs
Vat-graded channel catfish averaging 10 cm and 15 cm were stocked into eight 0.1-ha ponds at 100,000 fingerlings/ha. Fish were fed once daily to apparent satiation and harvested 210 d after stocking. Mean yield was 9,202 +/- 1,394 kg/ha; FCR averaged 2.0 +/- 0.6; and survival averaged 33 +/- 10%. There were no significant differences )P>0.1) between treatments. The 15-cm fingerlings reached a size significantly larger than the 10-cm fingerlings (P<0.1). Enterprise budgets were developed based on three sizes of farm (65, 130, and 260 ha) and eight production strategies to identify profit-maximizing strategies for a whole catfish farm. The 37-g multiple-batch purchased stocker strategy was the most profitable. The second most important profit-maximizing strategy for larger farms was on-farm production of 255-g stockers. Sensitivity analyses indicated that the results were robust to variation in production characteristics and prices. The most profitable strategy varied
only between the 37-g purchased stocker and the 255-g on-farm produced stocker. Risk analysis indicated that the 37-g purchased stocker was associated with the lowest levels of economic risk.
Impacts
There is a great deal of interest in a three-phased catfish production strategy. This analysis indicates those farm conditions under which on-farm stocker production would be the more profitable option. For most farms and conditions, on-farm stocker production may not be the most profitable option.
Publications
- Pomerleau, S. and C.R. Engle. 2003. Production of stocker-size channel catfish: effect of stocking density on production characteristics, costs, and economic risk. North American Journal of Aquaculture.
- Engle, C.R. and D. Valderrama. 2002. Production characteristics, costs, and risk of producing channel catfish, Ictalurus punctatus, fingerlings on farms with thinning. Journal of Applied Aquaculture 12(2):51-64.
- Pomerleau, S. and C.R. Engle. 2002. Economic analysis of channel catfish production. Annual Research Forum 2002, UAPB.
- Pomerleau, S. and C.R. Engle. 2002. Stocker channel catfish Ictalurus punctatus production at three different stocking sizes. Aquaculture America 2002, San Diego, California.
- Pomerleau, S. and C.R. Engle. 2002. Stocker channel catfish Ictalurus punctatus production at three different stocking sizes. Mid-year meeting, Southern Division, American Fisheries Society, Little Rock, Arkansas.
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Progress 01/01/01 to 12/31/01
Outputs
A pond production trial was conducted to compare yield, growth, feed conversion ratio, cost, and economic risk of producing catfish stockers at three different stocking rates. 5-8 cm channel catfish fingerlings (averaging 2.8g) were stocked into twelve 0.1 ha ponds at rates of either 49,420; 98,840; or 148,260 fingerlings/ha. There were four replicates of each treatment. Fish were fed once daily to apparent satiation with 32% protein floating catfish pellets. Ponds were aerated nightly with a 1/2-hp floating electric paddlewheel aerator. Net yield (kg/ha) increased with stocking rate (y = 26.311 x 0.4722 (superscript), R2 (2 superscript) = 0.65) while average weight at harvest (176 +/- 29g) at 49,420/ha; 135 +/- 10g at 98,840/ha; and 114 +/- 23g at 148,260/ha) decreased as stocking rate (no./ha) increased (y = -55.976 < n (x) + 780.13, R2 (2 superscript) = 0.65). There were no significant differences (P > 0.05) in survival, feed conversion ratio, or condition among
treatments. An enterprise budget analysis was used to compare the relative production losses of the various stocking treatments to produce stocker catfish. The lower yield at the lowest density resulted in a higher cost per fish, per kg, and per cm. However, the medium and the highest density resulted in very similar costs.
Impacts
There is increasing interest in a three-phased catfish production strategy. This study provided basic production data to begin to evaluate the relative trade-offs among stocking densities to produce stocker catfish.
Publications
- Engle, C. R. and D. Valderrama. 2002. Production characteristics, costs, and risk of producing channel catfish fingerlings on farms with thinning. Journal of Applied Aquaculture.
- Dasgupta, S. and C. R. Engle. 2002. Can commercial catfish producers always feed efficiently? Aquaculture Economics and Management.
- Engle, C. R. and D. Valderrama. 2001. An economic analysis of the performance of three sizes of catfish (Ictalurus punctatus) fingerlings understocked in multiple-batch production. Journal of the World Aquaculture Society 32(4):393-401.
- Engle, C. R. and D. Valderrama. 2001. Effect of stocking density on production characteristics, costs, and risk of producing fingerling catfish. North American Journal of Aquaculture 63(3):201-207.
- Engle, C. R. 2001. The economics of producing and understocking different sizes of catfish fingerlings on growout farms. University of Arkansas at Pine Bluff Cooperative Extension Program EBT 255, Pine Bluff, Arkansas.
- Dasgupta, S. and C. R. Engle. 2001. Modeling continuous multi-batch production of channel catfish. Abstract. Forum on Fisheries Economics, North American Association of Fisheries Economists, New Orleans, Louisiana.
- Dasgupta, S., D. Monestime, and C. Engle. 2001. Can commercial catfish producers always feed efficiently? Abstract. Aquaculture 2001, The International Triennial Conference and Exposition of the World Aquaculture Society, Orlando, Florida.
- Pomerleau, S. and C. R. Engle. 2001. Effect of stocking density on production characteristics and costs of producing stocker channel catfish (Ictalurus punctatus). Abstract. Aquaculture 2001, The International Triennial Conference and Exposition of the World Aquaculture Society, Orlando, Florida.
- Pomerleau, S. and C. R. Engle. 2001. Effect of stocking density on production characteristics and costs of producing stocker channel catfish (Ictalurus punctatus). Annual Meeting of the Arkansas Chapter of the American Fisheries Society, Heber Springs, Arkansas.
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Progress 01/01/00 to 12/31/00
Outputs
A pond production study was conducted to compare net yield, growth, survival, costs and economic risk of understocking 7.6-cm, 12.7-cm, and 17.8-cm channel catfish (Ictalurus punctatus) fingerlings in growout ponds. Fingerlings were understocked at 15,000/ha with 1,369 kg/ha carryover fish averaging 0.58 kg. Mean growth rate increased with size of fingerling understocked (1.4 +/- 0.2 g/d, 1.8 +/- 0.07 g/d, and 2.2 +/- 0.06g/d for 7.6-cm, 12.7-cm, and 17.8-cm understocked fingerlings, respectively). Mean individual weights at harvest also increased significantly with size at stocking but none of the understocked fingerlings reached minimum market size (0.57 kg) over the study period. Survival of the smallest (7.6-cm) understocked fingerlings was significantly lower, but there was no difference in survival between the two other treatments. Net yields were highest for the two treatments understocked with 12.7 and 17.8-cm catfish and significantly lower for the treatment
understocked with 7.6-cm fish. Breakeven production costs were highest for the treatment understocked with 7.6-cm fish and lower for the other two treatments. The risk analysis showed very little risk associated with growing out 12.7 and 17.8-cm understocked fish at costs less than $1.32/kg - $1.65/kg. However, the risk of growing out 7.6-cm understocked fish at costs above market prices increased sharply.
Impacts
This static analysis indicated that the preferred size to understock in growout ponds would be 12.7 cm; however, additional work is needed in a dynamic framework to quantify the benefit of 17.8-cm fingerlings reaching market size earlier in the second year.
Publications
- Engle, C. R. and D. Valderrama. 2001 (In Press). Effect of stocking density on production characteristics, costs, and risk of producing fingerling channel catfish. North American Journal of Aquaculture.
- Pomerleau, S. and C. Engle. 2001. A partial budget analysis of the economics of producing stocker catfish (Ictalurus punctatus). Book of Abstracts. Annual Meeting of the World Aquaculture Society, Orlando, Florida.
- Engle, C. and D. Valderrama. 2000. Economically optimum size of fingerlings to understock in multiple-batch catfish production ponds. Poster Abstracts. Aquaculture/Fisheries Center of Excellence Field Day, UAPB, Pine Bluff, Arkansas.
- Pomerleau, S. and C. Engle. 2000. Costs of producing stocker catfish with three different stocking densities: a study in progress. Poster Abstracts. Aquaculture/Fisheries Center of Excellence Field Day, UAPB, Pine Bluff, Arkansas.
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Progress 01/01/99 to 12/31/99
Outputs
Channel catfish (Ictalurus punctatus) fry (averaging 0.043 g each) were stocked into 0.04 ha earthen ponds at 625,000 fry/ha. Ponds were managed according to commercial catfish fingerling production practices. After 5 weeks, catfish fingerlings averaging 1.84 g weight and 5.6 cm length were partial harvested and restocked into 0.04 ha earthen ponds at rates of either 291,500/ha, 145,750/ha, or 70,000/ha. Average weight at harvest increased significantly with decreasing densities (33.5 + 5.9 g at 70,000/ha; 22.8 + 2.0 g at 145,750/ha; 13.4 + 1.9 g at 291,500/ha; and 16.7 + 3.9 g in the original fry ponds). Survival was highly variable within treatments, but was not significantly different (P > 0.05) among treatments, resulting in significantly greater numbers of fingerlings produced and greater yields at higher densities. There were no significant differences in feed conversion ratio or in condition of the fish. The higher densities resulted in lower costs/ha,
/fingerling, /kg, and /cm of fingerling produced. Definitive farm recommendations cannot be made until additional research is done to determine the relative value of different sizes of fingerlings when understocked in growout ponds.
Impacts
This is the first study to produce experimental production data as the basis for estimating production costs of different sizes of fingerlings. This data will provide a basis to improve farm- level decision-making on commercial catfish farms.
Publications
- Engle, C. R. and D. Valderrama. 2000. Production characteristics and cost of producing channel catfish fingerlings with and without thinning. Book of Abstracts. Catfish Farmers of America Research Symposium, Albuquerque, New Mexico.
- Engle, C. R. and D. Valderrama. 2000. Production characteristics, cost, and risk of producing channel catfish fingerlings without thinning. Abstracts of Aquaculture 2000, Annual Meeting of the U.S. Chapter of the World Aquaculture Society, New Orleans, Louisiana.
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Progress 01/01/98 to 12/31/98
Outputs
This project is only three (3) months old. An experimental protocol has been developed for the first year's experimental work. Ponds are being prepared to initiate the work. Broodstock have been selected for this spring's spawning season, fry handling equipment has been purchased, the appropriate sizes of graders have been purchased, and other necessary materials have been ordered.
Impacts
(N/A)
Publications
- No publications reported this period
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