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1.
Periodic grading and harvesting of fish has been shown to increase production of some species by removing larger fish throughout the growing season, reducing overall biomass, and increasing growth of smaller fish. Two two-year studies measured production and economic effects of the UAPB grader as compared to traditional live car grading and assessed effects of frequent harvesting and grading. Multi-batch production systems were used in both studies. In Study 1, fingerlings grew significantly better in ponds graded with the UAPB grader (0.97 g d−1) as compared to the traditional live car (0.80 g d−1) and resulted in 14% fewer under-sized (<0.57 kg) fish sent to the processor. In Study 2, increased frequency of harvest up to four harvests a year resulted in significantly fewer over-sized fish (>1.51 kg), more frequent receipt of revenue, and improved cash flow. Economic analysis showed that: (1) it was economically advantageous for catfish farmers to switch to the UAPB grader under a variety of farm size and processor dockage scenarios; and (2) increasing the frequency of harvest up to four harvests/year resulted in fewer over-sized fish, less dockage at the processing plant, improved cash flow, and more favorable economic outcomes.  相似文献   

2.
Grading trials were performed in experimental and commercial catfish ponds to compare an in-pond horizontal floating bar grader to current live-car grading. Three replicate trials were conducted in experimental ponds at three different temperature ranges (warm, >26 °C; cool, 13–26 °C; cold, <13 °C) with catfish size groups stocked in ratios of either 75:25, 50:50, or 25:75 sub-marketable (<0.57 kg) to marketable fish (≥0.57 kg). Commercial pond trials were replicated three times at each temperature range with a fish size range typical of ponds ready to harvest. Stress experienced by fish during harvest and grading was measured by mean serum glucose and cortisol levels. Grading speed was greater (P < 0.05) with the UAPB grader (105–449 kg/min) than the traditional live-car grader (0.5–0.6 kg/min). The UAPB grader decreased (P < 0.05) the proportion of sub-marketable fish during all trials. In contrast, the live car did not reduce the proportion of sub-marketable fish with the experimental methods used in this study during commercial trials or in the 25:75 distributions during warm and cold temperature trials in experimental ponds. The UAPB grader returned an average two to four times (range of 2–52) more sub-marketable fish by weight to the pond than the traditional live car method. Glucose and cortisol levels in fish graded with the two technologies were not significantly different. The UAPB grader sorted fish more accurately, consistently, and quickly than the live car at all temperatures in both experimental and commercial trials.  相似文献   

3.
Growth, production and economic analysis was performed for the polyculture of juveniles spotted babylon, Babylonia areolata, and milkfish, Chanos chanos, to marketable sizes using a large‐scale production of earthen ponds in Thailand. The analysis was based on actual cost and production data from a pilot commercial‐scale farm. A total farm area of 0.8 ha was comprised of 0.3 ha grow‐out earthen ponds, a 0.4 ha seawater reservoir, and a 0.08 ha accommodation and office. Each pond was stocked with spotted babylon juveniles of 0.3 g initial body weight at a density of 200 snails m?2, and they were harvested at a 7‐month period, at an average body weight of 4.6 g for a total yield per production cycle of spotted babylon and milkfish of 9875 and 6875 kg ha?1 respectively. Based on farm data and harvest data used in this study, initial investment requirement was estimated to be $4837. The ownership cost and operating cost per production cycle were $2241 and $18 501 respectively. Total cost per production cycle was $20 742. The cost of producing spotted babylon marketable sizes in this grow‐out farm design was $6.56 kg?1. The enterprise budgets based on the price of spotted babylon at a farm gate in 2003 of $9.00 kg?1 results in gross return, net return, return to capital and management, and return on investment of $31 190, $10 448, $12 689 and 2.62 respectively. Milkfish was not calculated for any returns because they were less than marketable sizes.  相似文献   

4.
Previous studies have indicated that the price premium charged for hybrid catfish fingerlings may be a significant factor in the adoption and profitability of hybrid catfish production. An enterprise budgeting simulation analysis was developed to compare costs, risk, and effect of hybrid fingerling costs. Feed, fingerling, and total costs ($/ha and $/kg) were highest for hybrid catfish production, intermediate for NWAC‐103, and lowest for normal channel catfish production. Net returns were highest for hybrid catfish production, but breakeven prices were also highest. Risk analysis showed that downside risk (risk of losing money) was higher for hybrid production for all farm sizes. Risk‐averse farmers would not select hybrid catfish at the mean fingerling values used in the analysis. However, at hybrid fingerling prices less than $0.0081/cm, hybrid catfish production was superior in profitability and breakeven cost of production. Thus, for hybrid catfish production to be preferred economically to normal channel catfish, the price premium for hybrid catfish fingerlings can be no more than 84% ($0.0037/cm) above that of normal channel catfish fingerlings and 57% ($0.0025/cm) above that of NWAC‐103 fingerling prices.  相似文献   

5.
Substantial economic losses of farmed catfish to fish‐eating birds such as the double‐crested cormorant, Phalacrocorax auritus, continue to be reported on U.S. catfish farms. An economic analysis was conducted of the on‐farm effects of both the increased expenditures to scare fish‐eating birds from catfish farms and of the value of the catfish that were consumed by cormorants. A survey was conducted of U.S. catfish farmers in the Delta region of Mississippi and Arkansas, to obtain farm‐level data on expenditures to scare birds. Estimations of the lost revenue from catfish consumed by cormorants were developed from a concurrent study on cormorant distribution, abundance, and diet in the region. The economic effects of bird predation in terms of both fish consumption and management costs were evaluated across three farm sizes and nine catfish production practices. Catfish farmers spent on average $704/ha ± $394/ha to scare birds, making bird‐scaring costs one of the top five costs of raising catfish. The greatest cost components of scaring birds were manpower (39% of all bird‐scaring costs) and the variable and fixed costs of trucks used to scare birds (34% of all bird‐scaring costs). Losses were greater on hybrid than channel catfish fingerling ponds. Industry‐wide, the value of catfish losses averaged $47.2 million (range of $25.8–$65.4 million). Total direct economic effects (including both the increased costs to scare birds and the revenue lost from fish consumed by cormorants despite bird‐scaring attempts) averaged $64.7 million (ranging from $33.5 to $92.6 million). Profitability improved by 4% to 23% across the farm size/production strategies analyzed upon removal of the economic effects from bird predation, with greater effects occurring on smaller‐scale farms. One‐third of the farm size and production scenarios analyzed changed from being unprofitable to showing a profit in the absence of such negative economic effects associated with bird depredation. Overall, the combined effects of increased farm expenditures to scare birds from farms and the value of the catfish lost to predation by cormorants caused substantial negative economic effects on catfish farms.  相似文献   

6.
Two concurrent pond studies were initiated in April 2011 to evaluate feeds containing solvent‐extracted distillers dried grains with solubles (SE‐DDGS) in both 28 and 32% protein catfish feeds. Channel catfish, Ictalurus punctatus, were stocked in multiple‐batch production ponds at the University of Arkansas at Pine Bluff (UAPB) and hybrid catfish, ♀ Ictalurus punctatus × ♂ Ictalurus furcatus, in single‐batch production ponds at the National Warmwater Aquaculture Center (NWAC), Mississippi State University, Stoneville, Mississippi, USA. The experimental design was a 2 × 2 factorial with two protein levels (32 and 28% protein), with and without 20% SE‐DDGS. Fish were fed once daily to apparent satiation, and managed similarly to a commercial farm for 186 d at UAPB and 172 d at NWAC. For channel catfish, two‐way ANOVA showed significant effects of both protein level (28% being better than 32%) and protein source (20% SE‐DDGS diets being better than traditional diets) on yield, survival, total diet fed, and feed conversion ratio (FCR), due primarily to effects on the understocked fingerlings. Partial budget analysis suggested that the 28% protein diet with the 20% SE‐DDGS was preferred economically for the prevailing feed costs. For hybrid catfish, two‐way ANOVA did not show significant differences in total diet fed, yield, survival, and processing yields, but use of SE‐DDGS resulted in a lower FCR. Results showed that both channel and hybrid catfish can utilize 20% SE‐DDGS in the diet without adversely affecting production or processing characteristics.  相似文献   

7.
An in‐pond confinement system to separate channel catfish, Ictalurus punctatus, by size within a single pond provides an opportunity for improved growth of understocked fish in ponds with larger market‐sized fish. A barrier of polyvinyl chloride–coated galvanized wire mesh was constructed in five 0.10‐ha earthen ponds to partition the pond into one‐third and two‐third sections, while five other 0.10‐ha ponds were left as traditional open ponds for a control. To evaluate catfish performance in this confinement system, fingerlings (25 g) were stocked at 14,820/ha into the smaller one‐third section of the barrier and carryover fish (408 g) at 2580 kg/ha into the larger two‐third section of the barrier. The control ponds were stocked with the same sizes and numbers of fish in a traditional earthen pond without a barrier. Yield, survival, feed conversion ratio (FCR), growth, and economics were compared between treatments. Fingerling yields were greater in the barrier system that allowed fingerlings to be separated physically from larger carryover fish. There were no differences in yield of carryover fish, survival, FCR, or growth between the control and the barrier ponds. Partial budget analysis revealed a positive net change of $367/ha or $38,125 for a 104‐ha catfish farm (at a market price of $1.54/kg of additional stockers produced). The value of the greater weight of understocked fish produced in the barrier system was greater than the annualized cost of installing the barrier, for farmers raising fish in multiple batch. Thus, on an experimental basis, the confinement system was economically profitable; however, trials on commercial farms are needed to evaluate performance on a larger scale.  相似文献   

8.
The economic performance of the current inshore rock bream aquaculture industry conducted in Yeosu, Korea was compared with a pilot commercial scale offshore aquaculture farm in Jeju, Korea. Data was collected from 12 inshore farms and two production cycles of the offshore farm for use in Monte Carlo simulations run over a ten year time horizon. Net present value was compared for the inshore farms and two survival rate scenarios for the offshore farm. The offshore farm is expected to have a higher survival rate if it can withstand tsunamis and avoid pollution, disease and red tide impacts that are prevalent inshore. When the offshore farm was modeled with its observed higher survival rate, its average net present value ($1,016,483) significantly outperformed the inshore farms average net present value ($182,153). In the second scenario, the offshore farm survival rate was lowered based on performance data from the inshore farms. Not surprisingly, given the higher investment costs, the offshore farm performed poorly in terms of average net present value ($-137,142) compared to the inshore farms when it no longer had the advantage of high survival rates.  相似文献   

9.
Integrated aquaculture systems have the potential to enhance the environmental sustainability of aquaculture production, if economically feasible. Data from integrated tilapia-prawn production trials were used to develop economic-engineering enterprise budgets for ponds with and without substrate that targeted two different types of markets, using two production scales and two forms of land tenure. Inclusion of substrate increased investment and fixed costs and decreased net returns. Recreational markets (live tilapia for fee fishing and live prawns as bait) were profitable, but sales to supermarkets were not. Production scale and land tenure affected economic outcomes with increased pond size and leasing ponds demonstrating greater profitability. Results provide evidence of the need to carefully evaluate economic trade-offs associated with varying commercial-scale applications to increase the likelihood of adoption of new technologies.  相似文献   

10.
Dockages can have a significant effect on catfish, Ictalurus punctatus, farm revenues. This study was conducted to quantify common dockages, examine seasonal and yearly variations in dockages assessed, and determine optimal production practices given various dockage scenarios. A convenience survey of invoice records from 30 commercial catfish farms and 10 processing plants provided 3686 daily catfish load records that were used to quantify dockages. A linear programming model was developed to examine optimal production practices given 11 alternative production scenarios with five size‐grading technologies subject to 24 types and levels of dockages. The survey revealed that 95% of catfish loads delivered to processing plants between 1997 and 2002 were assessed dockages that resulted in average losses of 2.45% per load or $0.066/kg of catfish marketed over the study period. Out‐of‐size discounts constituted the greatest losses. Dockage losses can be reduced by shifting either to longer‐term single‐batch production or more intensive grading. Longer‐term production results in fewer smaller fish that would incur dockage losses. However, cash flow constraints require more intensive early‐season grading. The grader choice depended on the dockage tolerance level and rate, the frequency distribution of sizes of catfish in the population, the efficiency of the grading technology, and the cost of the grading method. Larger farms minimize losses with intensive active grading (University of Arkansas at Pine Bluff grader).  相似文献   

11.
A bioeconomic model of reservoir aquaculture in northern Vietnam is used to investigate the impacts of fish price and yield variability on the level and riskiness of expected net revenue. Net revenue is volatile compared with similar enterprises in other countries, mainly due to high yield variability. This reflects the nascent nature of the industry in Vietnam and the potential for efficiency and productivity improvements. Increasing production intensiveness, as well as reservoir size, was found to increase profits and decrease revenue risk. Among the management parameters studied, expected net revenue was found to be most sensitive to the length of the production cycle and to the harvest rate, while revenue risk was most sensitive to cycle length. Reservoir size was found to affect net revenue less than anticipated. Although common carp monoculture was found to maximize expected profit, the current species mix minimizes risk, thereby suggesting high risk aversion by northern Vietnam's poor farmers.  相似文献   

12.
Previous research has shown that winter feeding is beneficial in preventing weight loss and maintaining catfish health. Although several studies suggest the importance of winter feeding of channel catfish, Ictalurus punctatus, less is known about optimal winter feeding strategies for channel‐blue hybrid catfish (♀ Ictalurus punctatus × ♂ Ictalurus furcatus). Three winter feeding treatments (unfed, fed daily, and fed based on temperature‐threshold feeding) were each assigned randomly to four replicate 0.10‐ha earthen ponds. All ponds were stocked with large channel‐blue hybrid catfish (0.96 ± 0.40 kg) at the rate of 3409 kg/ha and fed using a slow‐sink 28% protein pelleted feed. The two feeding treatments showed significantly greater mean weight at harvest, gross yield, and growth rates than the unfed fish after the 113‐d winter trial. Partial budget analysis indicated that additional costs incurred from the additional feed, fuel, and labor costs over the winter in fed treatments offset the additional revenue from daily winter feeding. However, in the temperature‐threshold feeding treatment, additional costs were similar to additional revenues when 10‐yr average prices were used. Results were sensitive to feed prices and spring catfish prices with positive net benefits from winter feeding at fish prices above $1.58/kg and feed prices below $0.286/kg.  相似文献   

13.
An industry advertising program for catfish, financed by farmers' voluntary contributions on feed on $6.00 per ton, commenced April 1987. This study estimates the impacts of that program on consumers' perceptions of catfish, purchase frequency, and profitability. Results indicate the ad campaign in its first year increased consumers' perceptions of product attributes (flavor, fishy odor, and nutrition) and overall attitudes toward catfish 2-4%, and increased purchase frequencies for at home and restaurant consumption 11-12%. The increased consumer demand for catfish attributable to advertising was estimated to have generated between $0.72 and $11.04 million in additional farm income in 1988, a net return of between $0.48 and $7.46 per media dollar invested. Results highlight the free-rider problem associated with voluntary programs: the estimated benefits of the advertising compaign were enjoyed by all producers yet only a portion shared in the cost. The profitability of industry advertising coupled with the inability to withhold benefits from non-contributing members provide a rationale for replacing voluntary contributions with a mandatory program. The issue of the optimal level of industry advertising must await further research.  相似文献   

14.
The Cost of Off-Flavor   总被引:1,自引:0,他引:1  
Off-flavor problems in farm-raised catfish Ictalurus punctatus increase production costs and pose inventory management problems for catfish farmers. Multiperiod mathematical programming techniques were used to test the effect of 16 different off-flavor scenarios on expected net returns above variable cost with and without cash flow restrictions. The patterns of off-flavor incidence had less effect on farm profits than whether or not fish are off-flavor during certain key months of the year. To be feasible, systems designed to purge off-flavor from catfish would need to cost less than $0.05 to $0.06/kg (if cash flow is not a consideration) or $0.04/kg to $0.25/ke (with cash flow considerations).  相似文献   

15.
This study analyzed the economic effects of intensifying baitfish production. An economic engineering approach was utilized to develop enterprise budgets for baiffish production that were used to conduct an economic analysis. All indicators utilized, including net returns, internal rate of return, and payback period, indicated dramatic improvement in the economics of baitfish production with yield increases. There were strong economic incentives to increase yield, and minnow production at industry average yield was only marginally profitable under certain scenarios and unprofitable under others. Yields of 600 kg/ha would generate adequate revenue to compete with other aquaculture alternatives in terms of net returns as well as generate M internal rate of return that would outperform current long-term interest rates.  相似文献   

16.
ABSTRACT

This work provides an analysis of the economic feasibility of one of many small-scale aquaculture operations being considered, black pearl oyster farms, as one type of supplemental economic activity for outer island communities in the Central Pacific. Specifically, projections of financial performance of a small-scale 25,000 seeded pearl oyster farm using the Tahitian long-line method are being conducted. Estimates of initial capital investment and annual operating costs are being formulated, an annual cash flow and enterprise budget are being developed. Results show that initial capital investment is $202,076. Annual operating expenses are $293,726 during full operation. The largest costs contributing to annual operating expenses are seeding (46%), labor including farm owner's opportunity cost (24%), and depreciation (9%). The base model presented in this work suggests profitability over a 20-year horizon.

Net returns over a 20-year farm horizon based on an 8% discount rate indicate a positive NPV of $ 102945. Sensitivity analysis on profit due to the variability of market price, survival, and cost of seed and other inputs are conducted and results presented.  相似文献   

17.
An economic analysis was performed of a proposed commercial-scale 20-ha saltwater pond culture operation for Florida red tilapia in Dorado, northern Puerto Rico. The analysis was based on actual cost and production data from a commercial-scale hatchery, pilot-scale grow-out trials conducted in six 0.2-ha saltwater (avg. = 22.7 ppt) ponds at the Dorado facility and on wholesale market prices ($4.96–5.18/kg) fetched by dressed-out (gilled, gutted and scaled) product. The proposed 20-ha growout facility is comprised of 25 0.8-ha earthen ponds, each supplied with sea water, brackish well water, drainage and aeration, which account for 60.8% of the capital costs. Ponds are stocked with fingerlings (0.85 g avg. wt.) at a density of 3.0 fish/m2 (30,000/ha), and are harvested at 160 and 220 d, at an average weight of 545 g for a total yield of 11,445 kg/ha per crop. Imported feed ($0.55/kg), processing and distribution ($0.50/kg) and sex-reversed fry ($0.11/fry) are the highest variable costs, accounting for 30.7%, 15.4% and 13.9%, respectively, of the total annual costs. Salaries and benefits, and depreciation represent the highest fixed costs, accounting for 8.4% and 5.5%, respectively, of the total annual costs. Under these conditions, a wholesale price of $4.55/kg results in a positive cash flow by year eight, and a breakeven price, internal rate of return (IRR), net present value (NPV) and discounted payback period (DPP) of $4.08/kg, 7.6%, ($235,717) and >10 yr, respectively, suggesting that the proposed 20-ha operation is not economically feasible under these conditions. The proposed enterprise is marginally feasible if stocking density is increased to 3.5 fish/m2 while at 4.0 fish/m2 economic outlook is favorable. Costs can be lowered considerably by targeting production and market variables most sensitive to profitability indices, using locally-prepared feeds, and vertically integrating hatchery and growout operations.  相似文献   

18.
This analysis compared the use of an intensive nursery raceway system with direct stocking of post-larval shrimp into growout ponds. The intensive raceway system allows two crops to be produced in Texas where only one crop is feasible with direct stocking. Both investment and operational costs are analyzed for three types of greenhouses and three types of raceways where the types vary in cost and lengths of life. Three growout pond stocking densities and two farm sizes were evaluated for each combination of greenhouse and raceway type. Investment costs ranged from $142,000 for the small farm using the least expensive greenhouse and raceway and utilizing the lowest stocking density, to about $2.3 million for the large farm using the most expensive greenhouse and raceway and the highest stocking density in the growout ponds. The operational cost was $7.60 and $9.71 respectively per 1,000 one gram juveniles produced. Under technology available at the time of this analysis, direct stocking growout ponds with PIS and producing one crop per year is more profitable than stocking one gram juveniles and producing two crops per year on the Texas coast.  相似文献   

19.
Abstract.– Although recent changes in coastal fisheries regulations in several Gulf states have renewed interest in the economic potential for culture of red drum S. ocellatus , few decision making tools with up-to-date information on production economics are available. From 1988 to 1995, estimates of investment costs, equipment specifications and typical input utilization in commercial-scale production were developed from field trials involving complete or partial grow-out of S. ocellatus . Operating costs and expected yields were subsequently estimated based on "best-case" data from a 70-wk production trial in which 5–7 cm fingerlings were stocked on 1 July and grown to marketable size by the following November, thus avoiding a second overwintering period and the associated risks of losses from freezing temperatures. To allow an evaluation of potential returns with earlier or staggered stocking dates, however, growth and mortality rates from the 70-wk trial were used in a computer-based simulation to estimate yields and costs associated with a hypothetical growout period beginning 1 April, deemed the earliest suitable date to avoid fingerling mortality resulting from abrupt or extreme cold temperatures. The April stocking simulation projected a preferred market size of 1.4 kg prior to a second overwintering period, with yield increasing from 3,454 kg/ha to 4,203 kg/ha and a reduction in breakeven costs from $5.97/kg to $5.53/kg. Partial budget analysis, based on a current average market price of $5.72/ kg, suggested April 1 stocking could result in a positive net change of $1,679 per ha over July 1 stocking.  相似文献   

20.
Abstract— Alternative fish species that can be cultured together with catfish Ictalurus punctatus provide an opportunity to diversify caffish farms. A 2-yr study was conducted in 0.10-ha earthen ponds to evaluate the effect of bighead carp (BHC) stocking density on growth, yield, dressout yield, and net returns. Initially, bighead carp (average weight of 22 g) were stocked at rates of 380, 750, or 1,130 fishha in ponds with catfish. Caffish were cultured under commercial conditions by stocking caffish at a density of 12,500/ha, aerating nightly and feeding at an average rate of 82 kgha per d. Stocking rates for 2-yr-old fish were reduced to 77, 260, and 435/ha in the second growing season. There were no significant differences among treatments ( P > 0.05) in summer growth of bighead carp in either year. Bighead carp stocked at 1,130 fishha had significantly higher yields than those stocked at 380/ha, but did not reach minimum market size of 2.2 kg during the first year ( P > 0.05). There were no significant differences ( P > 0.05) in caffish growth, yield, survival, or feed conversion ratios due to the bighead carp stocking densities. Partial budget analysis indicated that net benefits were positive for all three treatments over a range of prevailing prices of bighead carp. Bighead carp production in catfish ponds is economically feasible over a wide range of prices. Given the market risk of producing smaller fish at the higher density, the medium density is the preferred stocking density of fingerling bighead carp in catfish ponds.  相似文献   

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