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Mean TL (mm), weight (WT, g), and sample size (N) per age of Channel Catfish and hybrid catfish collected from production farms in western Alabama. Numbers in parentheses are standard errors.
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Processing plants prefer live catfish ranging from 0.45 to 1.81 kg as they are readily processed and sold to established markets. Catfish routinely escape harvest, become Big Fish (> 1.81 kg) in one to two production cycles, receive a reduced price, and can reduce farm profitability. This study determined age structure of Channel Catfish (Ictalurus...
Context in source publication
Context 1
... Channel Catfish ranged from 382 to 725 mm TL and 0.54 to 4.87 kg, whereas hybrid catfish ranged from 409 to 1,067 mm TL and 0.76 to 20.64 kg ( Figure 1). Mean TL and weight of hybrid catfish were larger than Channel Catfish at every age-class sampled (Table 1), and hybrid catfish were significantly longer (|t| range = 4.23-5.42; P ≤ 0.0019) and heavier (|t| range = 4.12-4.97; ...Citations
... Chatakondi, US Department of Agriculture, personal communication). Hybrid catfish exhibit faster growth, lower feed conversion ratio, improved disease resistance, improved fillet yield and dress out percentage, improved tolerance to low dissolved oxygen, faster growth compared with channel catfish, and increased seinability (Arias et al., 2012;Bosworth et al., 2004;Creel et al., 2021;Dunham et al., 1983;Dunham et al., 1987;Dunham et al., 2014;Dunham & Argue, 1998;Dunham & Masser, 2012;Yant et al., 1976). Research into improvement of hybrid catfish typically focuses on production, and comparatively few articles have investigated the resulting fillet quality and texture comparisons between channel catfish and hybrid catfish (Bosworth et al., 2004;Li et al., 2020;). ...
... The catfish industry has a problem with oversize catfish (>1.75 kg), both channel catfish and hybrid catfish (Creel et al., 2021). Processors pay a low price for these fish or refuse to pay for them at all. ...
Despite catfish being the dominant freshwater aquaculture product in the United States, catfish texture and sensory evaluation are understudied compared with other aquaculture species, and very few studies have been conducted to evaluate these traits in catfish. Texture, sensory, carcass yield, flavor, visceral fat deposition, gonadal development, and fillet color analyses were conducted on four size classes, small (<0.68 kg), medium (0.68–0.92 kg), large (0.93–1.75 kg), and extra‐large (>1.75 kg), for channel catfish (n = 456) (Ictalurus punctatus), blue catfish (n = 78) (I. furcatus), and hybrid catfish (n = 195) (channel catfish ♀ × blue catfish ♂). Within genetic type comparisons indicated that the texture traits, hardness, and chewiness and the sensory trait toughness increased with increasing size in hybrid catfish and channel catfish but were the most pronounced in channel catfish. Overall, channel catfish had the firmest fillets based on several attributes. Blue catfish were found to have differences among texture traits between the extra‐large size class and the three remaining size classes, but overall size had less of an effect compared with the channel catfish and hybrid catfish. A trend of paternal predominance was observed as the hybrid catfish was more similar to the blue catfish than the channel catfish. Hybrid catfish had the highest fillet percentage. This study is the first large‐scale analysis of texture and sensory traits within two catfish species and their interspecific hybrid at different sizes and highlights the differences in commercially important texture and sensory traits.
... The market size of catfish demanded in the marketplace ranges from about 0.45-1.81 kg (Creel et al., 2021). To sell fish, farmers must produce the size of catfish demanded in the marketplace, the fish must be on-flavor, and a processor must agree to schedule those fish for processing . ...
... The lack of evidence that management decisions result in either higher or lower FCR suggests that other, less controllable factors play a greater role in farm FCR values. For example, FCR values are affected by very large catfish in ponds in multiple-and single-batch culture and channel as well as hybrid catfish ponds (Creel et al., 2021). These large fish (>3.6 kg to sizes exceeding 20 kg) are those that escaped the large commercial seines during harvest. ...
Feed conversion ratio (FCR) is widely used as a measure of feed use efficiency in commercial aquaculture production and research. Surprisingly, little work has focused on the factors that affect FCR in plankton‐based, commercial ponds despite the widespread use of FCR as a production metric. Proposals to use FCR as a numeric standard for environmental regulation (mandatory or voluntary) raise questions as to whether FCR meets the reliability and consistency requirements of a good metric, and whether it would lead to desired behavioral changes. This article summarizes FCR data from university research verification programs conducted on US catfish farms and databases developed from commercial farm records. The relevant research literature is synthesized with respect to factors that affect FCR. US catfish is used as a case study because pond‐level data from verification trials (Extension/research‐led on‐farm trials of best available science) and commercial farm records are available. While specific to US catfish production, the analysis provides insights into factors affecting FCR that likely apply to other pond‐based aquaculture species. Commercial verification of pond data showed (1) significant variation in FCR (coefficients of variation from 1% to 47%) among ponds with similar stocking, feeding, and aeration rates; (2) significant effects of survival on FCR; and (3) no significant effects on FCR of yield, feed type, management, or production system. Improvements in FCR would occur with improved survival that requires improved management of federally protected fish‐eating bird populations and development of additional, effective vaccines for diseases. FCRs were found to not exhibit the degree of reliability and consistency required for use as an effective metric or numeric standard for regulatory purposes. Use of FCR for mandatory or voluntary regulation is unlikely to lead to behavioral changes by farmers.
... This could be due to our study's single fish production crop, which was enough to achieve the fish size suitable for the Brazilian market. Catfish are processed at 1-2 kg in Brazil which can be achieved in 8-10 months (Frasc a-Scorvo et al. 2008), while in the US catfish production may take longer than a year, 11-17 months (Creel et al. 2021), and are processed at 1-1.8 kg. ...
Hybrid cachapinta (Pseudoplatystoma reticulatum × Pseudoplatystoma corruscans) has been a very popular fish and is well accepted by consumers internationally, however, there is a lack of information showing its advantages relative to its parental cachara (P. reticulatum) species. This study was undertaken to compare the processing yield and meat quality characteristics of cachara and the cachapinta hybrid raised in net cages. Cachara’s weight was 1.51 ± 0.27 kg and total length was 49.85 ± 6.22 cm at harvest and was not significantly different from hybrid cachapinta that weighed 1.50 ± 0.11 kg and measured 50.83 ± 3.91 cm. Additionally, the two groups were not statistically different on gutted fish dress out (cachara: 89.97 ± 1.28%; cachapinta: 90.23 ± 0.30%) and other processing yield parameters. Skinless shank fillets with an average weight of 503.77 ± 0.10 g (cachara) and 514.41 ± 0.04 g, (hybrid cachapinta) were evaluated for pH, water holding capacity, colour (L*, a*, b*), shear force and lipid oxidation (TBARS). There were no differences in the fillet meat quality between cachara and hybrid cachapinta tested in this study. In conclusion, both genetic groups had similar processing yield and fillet meat quality characteristics when produced in net cages.
• HIGHLIGHTS
• The perceived improvements in growth and disease-resistance generated by hybrid vigour are the main reasons for interest and use of hybrid fishes.
• It is difficult to systematically predict processing yield and meat quality obtained from hybrids.
• Processing yields and meat quality are similar for cachara and hybrid cachapinta produced in net cages.
... Even after import, Southeast Asian intensively farmed Swai Catfish is priced lower than U.S. farmed catfish due to unfair trading practices (dumping), differences in regulatory stringency, and lower input costs (Quagrainie and Engle 2002;Engle and Wossink 2008;Engle et al. 2017;Hanson 2020;NOAA 2020). United States production costs are higher due to increasing feed costs, lack of inventory control due to use of multiple-batch production systems, the "big fish" problem (Creel 2020) in which produced fish are too large for processor needs, and other factors leading to inefficiencies. ...
... When the net benefits of vaccinated fingerling use are extrapolated to a 101-ha farm, a typical catfish farm size found in west Alabama (Creel 2020), there would be a potential additional benefit of $160,560 due to an increase in harvest weight plus a decrease in feed cost. Additional costs now total $14,847, as we would expect to vaccinate over 355,000 fingerlings and account for additional transport and loan interest costs. ...
While Flavobacterium columnare is a well‐known fish pathogen that has been studied for over 100 years, columnaris disease remains poorly controlled and in need of improved management solutions for United States catfish producers. Outside of therapeutants, the disease remains relatively unchallenged in the commercial catfish industry. Attempts to improve the management of this disease have led to the development of a live‐attenuated genetic group 2 F. columnare vaccine (hereafter 17‐23) administered via immersion to fingerling stage Channel Catfish (Ictalurus punctatus). The 17‐23 vaccine was confirmed to protect against F. columnare in Channel Catfish fry in previous studies. The current study investigates and compares the efficacy of the 17‐23 vaccine on Channel Catfish fingerlings versus non‐vaccinated (control) fingerlings grown to foodsize fish in earthen ponds. Data were collected from the two treatments (n=5 per treatment) to evaluate impacts on survival, growth, feed conversion, antibody development, and economic benefit. There were no natural outbreaks of columnaris disease observed during the trial and no significant difference in survival of vaccinated versus control fish (P = 0.7127). Indirect ELISA results determined that the anti‐F. columnare 17‐23 antibody concentrations were significantly higher in vaccinated fish at 4 weeks post‐vaccination (P < 0.05) but not at 12 weeks (P = 0.334). Vaccinated fish had a significantly higher average weight at harvest (357.5 ± 30g) than control fish (289.3 ± 20g) (P = 0.0013), and the feed conversion ratio (FCR) of vaccinated fish (1.35) was significantly better than control fish (2.13) (P < 0.0001). Partial budget analysis of changing production from use of non‐vaccinated fingerlings to use of 17‐23 vaccinated fingerlings for growout resulted in a net benefit of US $1,443/ha. Based on these results, the vaccine appears to show potential economic benefit to producers but should be further substantiated under both research and commercial settings.
Objective: In West Alabama, catfish Ictalurus spp. producers routinely face the challenge of fish that exceed market size (aka “Big Fish”) in their commercial ponds.
These fish are skilled at evading seine nets during harvest and can increase in size
significantly before subsequent harvests occur. This is problematic for catfish producers because processing plants prefer catfish within the 0.45–1.81-kg
range and farmers are paid a premium price for catfish of this size. Due to their larger size and growth potential, hybrid catfish (female Channel Catfish Ictalurus
punctatus × male Blue Catfish I. furcatus) can become a more significant issue than Channel Catfish if they evade harvest. The objective of this study was to describe and quantify the age structure and growth rate of hybrid catfish that evade capture and remain in commercial ponds following harvest and grow beyond acceptable market size as defined by catfish processing plants (i.e., Big Fish).
Methods: Hybrid catfish were collected from 12 recently harvested commercial
ponds in West Alabama from December 2021 to August 2022 using an electroshocking boat. Total length (mm), body weight (kg), and sex of collected fish were recorded, and lapilli otoliths were removed to estimate fish age and determine total length and total body weight at estimated ages.
Result: In this study, 1005 hybrid catfish were collected with the successful age estimation for 1001 catfish, ranging from 1 to 11 years. Results of this study indicate
that hybrid catfish exceeded the premium size threshold in 2.72 years ± 8 months.
Additionally, from age 2 to age 3, the average hybrid catfish gained 2.90 kg, growing
from 0.40 to 3.30 kg. Growth rate was significantly affected by sex; males overall were predicted to weigh more than females based on the weight-at- age model.
Conclusion: Hybrid catfish should be completely harvested from commercial ponds
following 1 year of harvest to receive the premium price per kilogram of live fish. If
a complete harvest is unsuccessful, farmers can receive a discounted price per kilogram of leftover hybrid catfish based on current market trends.
Variation in harvest size of ictalurid catfishes can be problematic for both catfish producers and processors, ultimately reducing profitability for both. Although harvesting and grading techniques can reduce this variation, the biological underpinnings of these size discrepancies remain unknown. Fry from Channel Catfish Ictalurus punctatus brooders that were 2–5 years old were measured to determine the amount of naturally occurring variation in body mass among sac fry and swim‐up fry. Over two spawning seasons, older brooders consistently produced larger sac fry (38–54% larger) and swim‐up fry (42–51% larger) than their younger counterparts. However, within‐spawn fry size variation was similar among all brooder ages measured. Regression modeling indicated that broodstock body mass did not influence fry body mass, whereas broodstock age was a significant predictor. These data reveal that brooder age is an important determinant of fry size and that initial fry body mass variation could be relevant to understanding fingerling size variation and may play a role in improving the production of ictalurid catfishes.
