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1.
In 2003, the United States adopted anti-dumping tariffs for Vietnamese catfish products entering the country. This study examines how these tariffs have impacted the price relationship between domestically produced and imported catfish products. Cointegration tests confirm a long-run price relationship between domestic and imported catfish, which has persisted despite the anti-dumping tariffs. However, imports are composed of catfish from Vietnam and other countries, with only the former subjected to tariffs. Results from vector error correction models suggest that Vietnamese catfish prices do not significantly influence domestic prices. Conversely, the price of catfish from countries other than Vietnam continues to impact prices received by domestic catfish farmers and processors. The domestic catfish industry is still affected by lower-priced imports from countries other than Vietnam, although some of these may be transshipments that truly originate in Vietnam. This research methodology could be adapted to investigate trade and price interactions among other aquacultured species, which will become increasingly important as global aquaculture expands.  相似文献   

2.
The study identifies the linkage between imports and the domestic price of crawfish. The results show a simultaneous increase in imports and domestic prices of crawfish while showing a negative relationship between domestic landings and price. Each model shows that there is a seasonality effect on the domestic price of crawfish. The study also shows that increases in the domestic supplies of shrimp, tilapia, and clams generated increases in the domestic crawfish price, while increases in imported and domestic supplies of beef and imported supplies of pork decreased the domestic crawfish price.  相似文献   

3.
Volatility in catfish pond bank and feed prices lead to profit uncertainty in the catfish industry. Analysis of the factors that affect those prices and development of a forecasting model would provide guidance to catfish farm managers. Error-correction models (ECM) based on cointegrating relationships among variables were specified following development of a single-equation ARIMAX model. Factors identified as those that influence catfish price were: lagged value of catfish, feed and substitute product prices, while those that influenced feed price were: lagged value of feed, corn and soybean prices. ECM estimates implied that fish price adjusts approximately 6% and feed price 22% to the long-run equilibrium in 1?month. The analysis showed that it takes less than 17?months and 5?months to correct for long-run disequilibrium for catfish and feed prices, respectively. The ARIMAX model demonstrated a better fit for both in-sample and out-of-sample forecasting for catfish price and had better out-of-sample predictive ability for feed prices.  相似文献   

4.
Abstract

In this paper, a time-varying student-t copula is used to capture information on price volatility dependence in the short-, medium-, and long-run horizon in the US market for frozen and fresh salmon, trout, tilapia and catfish. Using monthly data from July 1992 to March 2017, the volatility dynamics for these aquaculture species are assessed. The analysis allows indicating significant differences in the volatility relationships, depending on time-frequency. While short-run volatility has limited dependency, there is significant dependency in both the medium- and long-run, indicating that market integration is stronger in the long-run. The information is particularly important to buyers and producers utilizing the futures markets, as contracts are typically traded using a set of frequencies, and may help them manage and reduce price risk.  相似文献   

5.
This paper looks at price integration in the aquaculture and wild-harvested African catfish market channels in Uganda. The issue of integration between the two market channels is important because African catfish has become an important traded species in Uganda with exports to regional markets rising even faster than production, yet limited research has been undertaken to understand price formation in the supply chain. The analysis draws on monthly price data from January 2006 to August 2013, and applies threshold autoregressive approaches to test for the existence of a long-run relationship and price asymmetry and to determine the time path needed for shocks to be transmitted from one market channel to the other. The results show that, over the studied period prices in both market channels are linked in the long-run, implying that farm-raised catfish forms part of the same market as wild-harvested catfish in the country. The findings have strong implications for aquaculture producers and artisanal fishers as they can serve as a basis for more efficient farm management and marketing decisions.  相似文献   

6.
Abstract

Economically efficient feeding levels in intensively stocked ponds might be below minimum biological feeding requirements under adverse market conditions. A catfish production function that estimated relationships between yield and stocking and feeding rates was used as the basis for estimating production relationships. Feed price boundaries were developed that allowed the feeding rate to exceed the minimum biological level but still reflected economically efficient rates over a range of catfish prices and producer risk preferences. At higher stocking densities (20,000/ha), the feed price upper bound is lower than at lower stocking densities. Producers stocking at higher rates will be less likely to maximize profit and meet minimum biological feeding requirements as feed price increases than those producers stocking at lower rates. However, if feed prices exceed the upper bounds calculated in this paper, producers should engage in feeding only at levels necessary to meet farm financial and cash flow obligations until such time as the feed price decreases.  相似文献   

7.
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   

8.
Catfish fillets with yellow coloration have become a prevalent problem for the catfish industry. This problem is due to the unacceptability in the market because the shift in fillet color is considered of lower quality by the consumers. To help the catfish industry better understand the yellow coloration of catfish fillet, a digital photography measurement method was developed to evaluate the yellowness. Sixty catfish fillets with a range of degrees of visible yellowness were taken directly from the processing line. The fillets were photographed in a light box with a digital camera. The photos were calibrated with the X-Rite ColorChecker standardized color target. CIELAB readings of the fillet photos were recorded, and the b* value was used to indicate the yellowness of catfish fillets. The xanthophyll levels of fillets were analyzed with high performance liquid chromatography. The actual xanthophyll level in catfish fillet was calculated as the sum of lutein, zeaxanthin, and alloxanthin. A linear correlation was found between the LAB b* values and xanthophyll levels of the 60 catfish fillets.  相似文献   

9.
The US catfish industry is evolving by adopting production‐intensifying practices that enhance productivity. Catfish producers have increased aeration rates over time, and some now use intensive rates of aeration (>9.33 kW/ha). Costs and production performance were monitored at commercial catfish farms using high levels of aeration (11.2–18.7 kW/ha) in Alabama, Arkansas, and Mississippi. A multivariate‐cluster analysis was used to identify four different management clusters of intensively aerated commercial catfish farms based on stocking density, size of fingerlings at stocking, and feed conversion ratios (FCR). Breakeven prices of hybrid catfish raised in intensively aerated pond systems were estimated to range from $1.86/kg to $2.17/kg, with the lowest costs associated with the second greatest level of production intensity. The two medium‐intensity clusters generated sufficiently high revenues for long‐term profitability. However, the least‐intensive and the most‐intensive clusters were economically feasible only when catfish and feed prices were closer to less probable market prices. Feed price, FCR, and yield contributed the most to downside risk. Intensive aeration in catfish ponds, up to the levels analyzed in this study, appears to be economically feasible under the medium‐intensity management strategies identified in this analysis.  相似文献   

10.
The cross-commodity price transmission is an approach to derive meaningful results from the price information, and is mostly influenced by the substitutability and complementary relations among products. Using time series data collected from the National Marine Fisheries Statistics, the present study specified and estimated cross-commodity price transmission models for 13 salmon products imported in the U.S. market. The salmon products are differentiated by form, cut, source/origin, and production environment. The estimated cross-product price transmission elasticity and degree of substitutability among them varied considerably. Whole fresh farmed Canadian and Norwegian Atlantic salmon did not have any close import substitutes in the U.S. market among the salmon products considered in the study. A reduced pricing strategy would result in an increase in U.S. salmon import market share of Chilean and U.K. Atlantic fillet fresh, if the U.S. import demand for it is relatively own-price elastic.  相似文献   

11.
A comparative study was conducted on growth and protein requirements of channel catfish, Ictalurus punctatus, and blue catfish, Ictalurus furcatus. Four diets containing 24, 28, 32, or 36% protein were fed to both channel (initial weight 6.9 g/fish) and blue (6.6 g/fish) catfish for two growing seasons. There were significant interactions between dietary protein and fish species for weight gain and feed conversion ratio (FCR). No significant differences were observed in weight gain of channel catfish fed various protein diets, whereas higher protein diets (32 and 36%) resulted in better weight gain in blue catfish than lower protein diets (24 and 28%). No consistent differences were observed in the FCR of channel catfish fed various levels of dietary protein, whereas significantly higher FCRs were noted in blue catfish fed the 24 and 28% protein diets compared with fish fed 32 and 36% protein diets. Regardless of dietary protein levels, blue catfish had higher carcass, nugget, and total meat yield, and higher fillet moisture and protein, but lower fillet yield and fillet fat. Regardless of fish species, fish fed the 36% protein diet had higher carcass, fillet, and total meat yield than fish fed the 28 and 32% protein diets, which in turn had higher yields than fish fed the 24% protein diet. It appears that blue catfish can be successfully cultured by feeding a 32% protein diet.  相似文献   

12.
A food consumption revolution is taking place in Russia. After decades of severe constraints on food consumption options under the communist regime Russian consumers are now adopting new food products—including seafood products – at a high pace. Since Russian consumers have previously had very limited seafood consumption choices, the market can be seen as an interesting laboratory for investigating consumer responses to products that have previously not been available. Among imported seafood products are both wild and farmed species. Furthermore, Russian imports include both traditional species such as herring, and ‘new’ species such as pangasius. We analyze market integration among seafood products using Russian monthly import prices from 2002 to 2007 on several products, such as herring, salmonids and pangasius. We find that pangasius compete in the white fish segment, and is a price leader. In the salmonids market, farmed salmon trout appears to be the price leader, both in the fresh and frozen market segment.  相似文献   

13.
High oleic corn is a genetic variant that contains more protein, lipid, and oleic acid and less linoleic acid than regular corn. A study was conducted to compare weight gain and feed conversion of year-1 and year-3 channel catfish Ietalurus punctatus , and processing yield, body composition and frozen storage stability of year-3 channel catfish fed high oleic corn and number 2 yellow (regular) corn in extruded production diets. A commercial-type diet formulated to contain 30% protein and made with regular corn served as a control. A second diet contained high oleic corn in place of regular corn on an equal (air-dry) weight basis. A third diet contained high oleic corn in substitution for regular corn and part of the soybean meal to limit protein content to 28%, which was equal to that of the control diet. The experimental diets were fed to year-1 channel catfish (average initial weight 5.1 g) in aquaria for 10 wk and to year-3 channel catfish (average initial weight 1.07 kg) in 0.04–ha ponds for 14 wk. Substitution of high oleic corn for regular corn on an equal (air-dry) weight basis provided significant gain ( P < 0.01) of year-1 channel catfish but not of year-3 fish. Use of high oleic corn diets designed to be equal in protein content did not affect weight gain of either group of fish. Replacement of regular corn with high oleic corn caused a significant ( P < 0.01) reduction in linoleic acid but no significant ( P > 0.20) increase in oleic acid in the flesh of fish. Proximate body composition, dressing yield, fillet yield, visceral fat, and liver weight were not significantly different among treatments. Sensory scores of fillets frozen for 3 and 6 mo were not significantly different among treatments. Peroxide value, thiobarbituric acid number and free fatty acids increased with frozen storage time but were not different among treatments.  相似文献   

14.
Corn germ meal (CGM) is a by‐product of corn milling. On the basis of its nutrient composition and digestibility values, it appears to be a suitable ingredient for use in channel catfish, Ictalurus punctatus, diets. A study was conducted to examine the use of various levels of CGM in diets for pond‐raised channel catfish. Four 28% protein diets containing 0, 15, 25, and 35% CGM were evaluated. Fingerling channel catfish (mean initial weight: 71 g/fish) were stocked into 24, 0.04‐ha ponds at a rate of 14,826 fish/ha. Fish were fed once daily to apparent satiation for a 167‐d growing season. No significant differences were observed in total amount of diet fed, diet consumption per fish, net yield, weight gain, feed conversion ratio, survival, fillet yield, and fillet protein, fat, and moisture concentrations among fish fed diets containing various levels of CGM. Carcass yield decreased linearly as dietary CGM levels increased. Depending on prices, CGM can be used interchangeably with corn gluten feed in channel catfish diets as replacements for corn, wheat middlings, and soybean meal to reduce feed cost.  相似文献   

15.
Abstract.— Bioelectric impedance analysis (BIA) was evaluated as a method for predicting carcass yield, fat, and moisture in live channel catfish, Ictalurus punctatus (N = 20), and fat and moisture in fillets from channel catfish ( N = 20) and channel catfish female × blue catfish male, I. furcatus , hybrids ( N = 20). Fish were cultured in ponds, fed a commercial catfish diet (28% protein), and harvested at market weight (450 g-900 g, ∼19 months post-hatch). Live channel catfish were tranquilized, weighed, and sexed. Resistance and reactance were measured with a four-terminal impedance analyzer. Fish were then deheaded, eviscerated, weighed, and carcass yield was calculated. Fillets from channel catfish and channel catfish × blue catfish hybrids were measured for weight, resistance, and reactance. Carcasses and fillets were ground and fat and moisture were determined by chemical analysis. Regression models including total weight, resistance, and reactance as independent variables explained 71%, 75%, and 65% of the variation in carcass yield, fat, and moisture, respectively, in live fish. Regression models with fillet weight, resistance, and reactance as independent variables explained 62% and 41% of the variation in fillet fat and moisture, respectively, in channel catfish, and 53% and 58% of the variation in fillet fat and moisture, respectively, in channel catfish × blue catfish hybrids. Models including resistance and reactance explained significantly more variation in the traits measured than did models containing only whole weight as an independent variable. Improvements in prediction accuracy will be needed to make BIA a useful tool for predicting carcass yield, carcass composition, and fillet composition in farm-raised catfish.  相似文献   

16.
A factorial experiment was conducted to examine effects of dietary protein concentration (24, 28, 32, or 36%) and feeding regimen (feeding once daily or every other day [EOD]) on channel catfish, Ictalurus punctatus, production in earthen ponds. Compared with fish fed daily, fish fed EOD had lower feed consumption, weight gain, net production, and percentage of market‐size fish but had high feed efficiency and required fewer hours of aeration. Fish fed EOD also had lower carcass yield, fillet yield, and visceral and fillet fat. There was a significant interaction between dietary protein and feeding regimen for weight gain. No significant differences were observed in weight gain of fish fed daily with diets containing various levels of protein, whereas weight gain of fish fed EOD with a 24% protein diet was lower than those fed EOD with higher protein diets. Results suggest that response of channel catfish to dietary protein levels depends on whether the fish were fed daily or EOD. Feeding EOD to satiation improved feed efficiency and required less aeration compared with fish fed daily but also reduced net production and processing yield; therefore, EOD feeding should be examined closely before implementation.  相似文献   

17.
The present study investigated the replacement of soybean meal with combinations of two or three alternative protein sources in diets for pond‐raised hybrid catfish, ♀ Ictalurus punctatus × ♂ Ictalurus furcatus. Alternative protein sources evaluated included cottonseed meal, distillers dried grains with solubles (DDGS), peanut meal, and porcine meat and bone meal (PMBM). Hybrid catfish fingerlings with a mean initial weight of 35 g/fish were stocked into 25 earthen ponds (0.04 ha) at a density of 14,826 fish/ha. Fish were fed once daily to apparent satiation for 166 d. No significant differences were observed for total diet fed, net yield, weight gain, survival, carcass yield, fillet yield, or fillet proximate composition among dietary treatments. Results show soybean meal may be completely replaced by combinations of cottonseed meal and one or two other alternative protein sources including DDGS, peanut meal, and PMBM in the diet without markedly affecting production and processing characteristics and fillet proximate composition of pond‐raised hybrid catfish. These alternative diets may be used during foodfish production when prices are favorable.  相似文献   

18.
Split ponds are recently developed pond‐based aquaculture systems that allow intensification of catfish aquaculture. Successful industry‐wide adoption of newly developing technologies like split‐pond systems will depend upon their productivity and cost efficiencies. Costs and production performance of the following three split‐pond design scenarios were monitored in Arkansas and Mississippi: (1) research design developed at the Thad Cochran National Warmwater Aquaculture Center, Stoneville, Mississippi; (2) waterwheel design tested on commercial catfish ponds; and (3) screw‐pump design tested on commercial catfish ponds. An economic engineering approach using standard enterprise budget analysis was used to develop estimates of breakeven prices (BEPs) ($/kg) for producing foodsize hybrid catfish (♂Ictalurus furcatus × ♀Ictalurus punctatus) for each scenario. Estimates of BEPs of hybrid catfish raised in split ponds ranged from $1.72 to $2.05/kg. The cost of catfish production in split ponds was sensitive to yield, fish prices, and feed prices. Annual net cash flows from both commercial split‐pond systems were high and sufficient to make the investment profitable in the long run. Feed price, feed conversion ratio, and yield contributed the most to downside risk of split ponds.  相似文献   

19.
Threadfin shad, Dorosoma petenense, or fathead minnows, Pimephales promelas, were co‐cultured with channel catfish, Ictalurus punctatus, in earthen ponds to determine the effects of planktivory on plankton community dynamics and catfish fillet quality. Fathead minnows had no effect on the plankton community structure or catfish fillet flavor, color, and fatty acid composition. Fillet color was also unaffected by the presence of threadfin shad. Small differences were found in fillet fatty acid composition for catfish from ponds with shad, but these differences probably have no biological significance. Threadfin shad did, however, have important impacts on the plankton community structure and catfish flavor. Size‐selective filter‐feeding by shad reduced cyanobacterial abundance relative to ponds with catfish‐only and fathead minnows. Relative abundance of smaller phytoplankton in the groups Chlorophyta, Cryptophyta, Bacillariophyceae, and Euglenophyta increased in ponds with shad. Relative abundance of small zooplankton (rotifers) also increased in shad ponds. Reduced abundance of large, colonial cyanobacteria that are known to produce odorous metabolites caused a corresponding reduction in off‐flavor prevalence and intensity in catfish from ponds with threadfin shad when sampled in September. Although threadfin shad dramatically reduced catfish off‐flavor prevalence during the warm season, they apparently caused a high prevalence of “fishy” off‐flavors in the February sample. This undesirable flavor appeared to be caused by catfish foraging on shad killed during a preceding period of exceptionally cold water temperatures. Use of threadfin shad for phytoplankton biomanipulation therefore presents a dilemma: catfish–shad polyculture reduces prevalence of cyanobacteria‐related off‐flavors in warm months but may cause undesirable forage‐related off‐flavors in the colder months. Catfish farmers must consider these benefits and risks when deciding to use threadfin shad as a management tool.  相似文献   

20.
Abstract

The study applies a dynamic model of the almost ideal demand system to derive long‐run estimates of demand for catfish products. Adjustment coefficients towards long‐run equilibrium for purchasers of catfish are estimated. The hypothesis that catfish buyers fully adjust to changes in real price and expenditure instantaneously is rejected. Following a deviation from equilibrium, about 16% of the adjustment takes place instantaneously while full adjustment is completed within the subsequent two‐month period. Purchasers of catfish adjust fairly quickly to a new equilibrium after disequilibrium movements suggesting a low cost of adjustment. Elasticity estimates obtained from the model indicate that the dynamic model is well behaved, with negative own‐price effects in the compensated and uncompensated form. In the uncompensated form whole fish is found to be less own‐price inelastic while fillet is found to be own‐price elastic. The sensitive nature of the products to changes in own prices suggests the need for processors to make whole fish and fillets more price‐competitive through efficient production and marketing processes. Expenditure elasticities obtained from the model are also consistent with economic theory.  相似文献   

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