Papers by Frederic Barrows
Journal of the World Aquaculture Society, 2003
This study was conducted to determine the effects of increasing dietary lipid concentrations on f... more This study was conducted to determine the effects of increasing dietary lipid concentrations on fillet characteristics of post-juvenile rainbow trout. A feeding trial was conducted with fish meal based diets containing 10, 15, 20, 25, or 30% lipid for 24 wk. Menhaden oil was the lipid ingredient. Weight gain was significantly greater in fish fed the 30% lipid diet than in fish fed either lo%, 15% or 20% lipid diets. There were no significant differences in visceral somatic index. Fillet lipid concentration of fish fed the 30% lipid diet (9.2-g lipid/ 100-g fillet) was significantly higher (P < 0.05) than fish fed either the 10% or 15% lipid diets (5.8-and 6.9-g lipid/lOO-g fillet, respectively). In samples stored for 3 d at 5 C or 8 wk at-20 C, sensory panelists reported that the cooked fillets from fish fed the 30% lipid diet were "more fishy" than fish fed the 15% lipid diet, and preferred the cooked fillets from the 15% lipid treatment over the 30% lipid treatment. Triangle tests and fillet colorimetry showed no significant differences between fillets from fish fed the 15% and 30% lipid diets at any sampling time point. No significant differences in fillet concentrations of thiobarbituric reactive substances were observed among dietary treatments stored at either 5 C or-20 C. These results suggest that two main effects of feeding a 30% lipid diet (with fish oil as the lipid source) are a higher lipid concentration in the fillet and a "fishier" aroma compared to fillets from fish fed a 15% lipid diet. * High-protein, steam-dried, low temperature Alaskan pollock, Alaska.
A 12-week growth trial was conducted to evaluate the complete co-replacement of fish meal (FM) an... more A 12-week growth trial was conducted to evaluate the complete co-replacement of fish meal (FM) and fish oil (FO) in juvenile Florida pompano (Trachinotus carolinus) diets. Five open-formula experimental diets were formulated as iso-nitrogenous (approximately 46% crude protein) and iso-lipidic (approximately 15% crude lipid). It is assumed that Florida pompano lack the mechanisms for synthesizing sufficient LC-PUFA. In the FM/FO-free diets, to meet the necessary dietary intake of LC-PUFA, a commercially available Schizochytrium algal oil was used. Four diets were prepared from a basal mix, with spirulina and poultry by-product meal as the principal protein sources. They differed only in their oil source, containing fish oil (FO), algal oil (AO), soy oil (SO), or a 50/50 blend of algal oil and soy oil (A/S). The fifth experimental diet (control) was a standard open-formula FM diet. In addition to the experimental diets, two commercial closed-formula diets served as references. The seven diets, each with four replicates, were stocked with 20 Florida pompano (approximately 4 g) in each. The experimental open-formula diets were tested against the control using Dunnett’s t-test, and different oil sources were tested against each other using orthogonal contrasts. The four experimental diets were each tested against the two reference diets with equivalency tests. Feed intake and survival were not different between the experimental diets and control. However, all production metrics were lower in the SO diet than the control. No other differences were observed between the FO, AO, and A/S diets and the control, or between the three diets. The feed conversion ratio (FCR) was higher in fish fed the SO diet than in fish fed the control diet, and no other differences were found. The protein efficiency ratio (PER) was higher in fish fed the control diet than in fish fed the experimental diets. Protein productive values (PPV) were similar to PER, except that the PPV in fish fed the AO diet was not different from the control. The contrasts revealed that the FO, AO, and A/S diets resulted in a lower FCR than the SO diet. The PER was higher in fish fed the AO diet, and lower in fish fed the SO diet. The PPV was higher in fish fed the AO diet than in fish fed the A/S and SO diets, but similar to that of fish fed the FO diet. There were striking differences in performance between the two commercial reference feeds, underscoring the importance of using well-defined open-formula diets as a reference or control. To our knowledge this is the first study to demonstrate that co-replacement of FM and FO can be achieved in Florida pompano by supplying an FM- and FO-free diet. The development of successful open-formula diets without FO will help spur innovation and sustainability in aquaculture production.
水産総合研究センター研究報告, Mar 1, 2015
In the wild, fish can adapt to their diet by down regulating or eliminating biosynthetic pathways... more In the wild, fish can adapt to their diet by down regulating or eliminating biosynthetic pathways for nutrients found in abundance in their prey. Upon domestication for aquaculture these fish may now have unique dietary requirements which must be met through supplementation. To examine this hypothesis and aid in determining potential minimum requirement levels for aquaculture production, we have examined the synthetic capacity for taurine and polyunsatured fatty acids in cobia, Rachycentron canadum, through molecular methods and growth trials, respectively. Taurine, a non-protein amino acid, is found in high concentrations in the natural diet of cobia and plays a variety of physiological roles. The taurine biosynthesis pathway in vertebrates is well known; however it appears to be nonfunctional in some terrestrial (Felidae) and marine (Rachycentridae) carnivores, thereby necessitating dietary supplementation. Taurine is not found in plant protein sources used for replacing fishmeal in aquaculture feeds, an increasingly important priority. We examined the effects of graded levels of taurine addition (0%, 0.5%, 1.5%, 5.0%) to plant protein and fishmeal based diets formulated and manufactured by the USDA-ARS. At the conclusion of a feeding trial, RNA was extracted from liver, muscle, and brain tissue for quantitative-RT-PCR analysis of the genes involved in taurine synthesis. Cysteine dioxygenase (CDO), cysteamine dioxygenase (ADO), and taurine transporter (TauT) activity and expression levels were examined and no differences in transcript abundance was detected within the tissues between the dietary taurine levels. Increasing dietary taurine resulted in increased tissue taurine concentrations. To examine the effects of alternative sources completely replacing fish oil, two replacements were examined as the lipid sources in a fishmeal free, plant based feed (USDA-ARS) and compared to a fish oil version of the diet. A thraustochytrid meal plus soybean oil (TM+SOY) and a canola oil with exogenous docosahexaenoic (DHA) and arachidonic (ARA) acids (CO+EFA) were utilized. At the conclusion of an eight week growth trial, whole body and fillet fatty acid profiles were examined. The TM+SOY diet worked equivalently to the USDA-ARS control diet, however the CO+EFA diet resulted in significantly lower growth and survival as well as an increased feed conversion ratio. Whole body fatty acid profiles revealed a significant reduction in total essential fatty acid (EFA) concentration in the CO+EFA fed fish, indicating the supplemented levels of DHA and ARA were insufficient to meet requirements. Although all three diets were sufficient in the precursors for EFA synthesis, this reduction in growth, survival, and whole body EFA concentration suggests cobia have limited synthetic capacity for DHA and ARA. Both alternative lipid diets were devoid of eicosapentanoic acid (EPA) supplementation, which does not appear to be essential for cobia as the TM+SOY diet performed equivalently to the fish oil control.
水産総合研究センター研究報告, Mar 1, 2015
Aquaculture Nutrition, Mar 16, 2017
Taurineisanimportantaminoacidderivativeformarineandfreshwaterfish, especially duringearlydevelopm... more Taurineisanimportantaminoacidderivativeformarineandfreshwaterfish, especially duringearlydevelopment.Weinvestigatedtherangeoftaurineconcentrationsthat influencethegrowthandsurvivalratesofCaliforniayellowtail(CYT;Seriola dorsalis) during transition from live feeds to microparticulate diets, as well as the extent to whichnutrientleachingfromthemicroparticulatedietsaffectstheseranges.Wetested particle-assistedrotationallyagglomerated(PARA)particleswithfourlevelsoftaurine: 4 (low taurine; LT), 45 (medium taurine; MT), 93 (high taurine; HT) and 122 g/kg (veryhightaurine;VHT).OurresultsshowedthatCYTpostlarvaehadnosignificant differencesingrowth,survivalandfeedconsumptionratesbetweentheMT,HTand VHT treatments. However, it should be noted that the PARA particles containing 122g/kg(VHT)taurinewereespeciallypronetoleachingandmayhavehadtaurine concentrations as low as 34.9g/kg before they settled on the bottom of the tank. Therefore,theactualdietarytaurineconcentrationsexperiencedbythelarvaewere likelylowerthantheinitialdietaryconcentrations.Moreresearchisneededtoevaluate the potential nutrient toxicity of elevated dietary taurine concentrations for marine fishlarvaeandjuveniles.
Comparative Biochemistry and Physiology Part D: Genomics and Proteomics, Mar 1, 2019
A twelve-week feeding trial was conducted to examine potential metabolic and gene expression chan... more A twelve-week feeding trial was conducted to examine potential metabolic and gene expression changes that occur in juvenile red drum, Sciaenops ocellatus, fed diets with increasing soybean meal inclusion. Significant reduction in fish performance characteristics (feed consumption, weight gain, final weight) was observed within the soybean meal based diets as soybean meal level increased (R, linear regression); however, all soybean meal based diets performed statistically equivalent in regards to performance characteristics (weight gain, feed conversion ratio, condition factor, etc.) to a commercial (45% crude protein and 16% crude lipid) reference diet (R, ANOVA). To better understand the underlying physiological responses and metabolic changes driving performance differences, traditional aquaculture metrics were paired with high throughput-omics techniques. Nuclear magnetic resonance (NMR) spectroscopy-based metabolomics data and RNA transcript abundance differences observed in liver tissue were utilized to select multiple sets of genes to target with quantitative polymerase chain reaction (qPCR), both for pathway activity validation and as rapid and accessible biomarkers of performance as a result of soybean meal. Genes selected based on the metabolic pathways most affected by soybean meal level corroborate the metabolite profile and performance data indicating an increase in gluconeogenic precursor production as soybean meal increased. The metabolomic and gene expression tools utilized in our study present a novel framework for diet and fish health evaluation that may provide more rapid and improved techniques for evaluating dietary manipulations and improving production of juvenile fish on alternative feeds. 2010); however, few commercial diets formulated specifically for carnivorous marine fish are available. Red drum, Sciaenops ocellatus, is a euryhaline, eurythermal, estuarine dependent marine carnivore with high potential for intensive and extensive culture expansion in the United States. Red drum have been spawned and raised in captivity and fed formulated feeds for several decades and culture methodology is well documented (Chambers et al., 1987; Robertson et al., 1987; Davis et al., 1995; Craig and Iii, 1997), making red drum an excellent model marine species.
Journal of the World Aquaculture Society, Aug 13, 2017
Many studies have evaluated the adequacy of alternate ingredient diets for Atlantic salmon, Salmo... more Many studies have evaluated the adequacy of alternate ingredient diets for Atlantic salmon, Salmo salar, mainly with focus on fish performance and health; however, comprehensive analysis of fillet quality is lacking, particularly for salmon fed these diets in recirculation aquaculture systems (RAS). To this end, a study was conducted comparing fillet quality and processing attributes of postsmolt Atlantic salmon fed a fishmeal-free diet (FMF) versus a standard fishmeal-based diet, in replicate RAS. Mean weight of Atlantic salmon fed both diets was 1.72 kg following the 6-mo trial and survival was >99%. Diet did not affect (P < 0.05) processing and fillet yields, whole-body proximate composition(fat, moisture, protein), fillet proximate composition, cook yield, fillet texture, color, or omega-3 fatty acid fillet content, including eicosapentaenoic acid and docosahexaenoic acid levels. Whole-body ash content was greater in salmon fed the FMF diet. The FMF diet resulted in a wild fish-in to farmed fish-out ratio of 0:1 per Monterey Bay Aquarium's Seafood Watch criteria due to its fishmeal-free status and use of lipids from fishery byproduct. Overall, fillet quality and processing attributes were generally unaffected when feeding a diet devoid of fishmeal to postsmolt Atlantic salmon cultured in RAS. KEYWORDS Atlantic salmon, fatty acids, fillet quality, fishmeal-free diet, recirculating aquaculture systems Over the last few decades, the price of fishmeal and fish oil has risen steadily due to relatively static supply and increasing demand, causing the aquaculture industry to consider alternate protein ingredients that are more economical and sustainable (Naylor et al. 2000, 2009; Gatlin
Transactions of The American Fisheries Society, Nov 1, 2001
Elevated temperature is considered an important factor in the decline of the threatened bull trou... more Elevated temperature is considered an important factor in the decline of the threatened bull trout Salvelinus confluentus, but the thermal requirements of this species have not been defined. We used the acclimated chronic exposure (ACE) method to assess the upper thermal limits and growth optima of bull trout fed daily to satiation over test temperatures ranging from 8ЊC to 28ЊC during 60-d trials. Survival of age-0 bull trout was at least 98% at 8, 10, 12, 14, 16, and 18ЊC, but 0% at 22, 24, 26, and 28ЊC after 60 d. The predicted ultimate upper incipient lethal temperature for these trout was 20.9ЊC. Peak growth, as estimated by regression analysis, occurred at 13.2ЊC (95% confidence interval, 10.9-15.4ЊC). Feed consumption declined significantly (P Ͻ 0.001) at temperatures greater than 16ЊC, and fish held at temperatures of 22ЊC and above did not feed. Feed, lipid, and protein efficiencies were similar at 8-18ЊC but declined significantly (P Ͻ 0.001) at 20ЊC. Our results corroborate field investigations suggesting that bull trout have among the lowest upper thermal limits and growth optima of North American salmonids. The slower acclimation times and long-term duration of the ACE method resulted in a more realistic measure of thermal tolerance in natural situations than would have been obtained with traditional methods and afforded sufficient time for sublethal differences in growth rate, feed consumption, and feed efficiency to become apparent.
Animal Feed Science and Technology, Mar 1, 2021
Abstract At present, aquafeed is made mainly by low-moisture extrusion cooking. To further improv... more Abstract At present, aquafeed is made mainly by low-moisture extrusion cooking. To further improve feed quality, we developed a new process featuring high-moisture extrusion with a twin-screw extruder and a specially designed cooling die. In this study, aquafeed was made with two mash formulations (with or without wheat flour) by low moisture (conventional) or high moisture (new) extrusion under the same temperature (138 °C). Fresh and/or dried extrudates were evaluated for visual appearance, physical quality (water absorption and hardness with soaking time, bulk density, pellet durability, water stability and oil absorption capacity), chemical composition and degree of starch gelatinization. Results show that processing methods, feed formulation and post-extrusion drying all had significant effects on the visual appearance and physical quality of feed. The new feed (NF) was less expanded and less porous than conventional feed (CF), leading to significant reduction in oil absorption capacity, about 85 % of CF. Upon contact with water, fresh and dried CF absorbed water quickly and disintegrated easily, while NF absorbed water slowly and maintained a soft texture (around 50 g/mm2, comparable to fish fillet texture) even after 24 h of soaking. Dry matter loss from NF was significantly less than CF, after 6 h shaking in water. Due to its compact texture, NF had higher pellet durability than CF, with a bulk density greater than 1 g/cm3. Addition of wheat flour to the mash made CF more porous, harder in texture and less water stable but exerted a limited effect on NF. Therefore, the new process produced aquafeed that was soft in texture, durable, and extremely water-stable, while making addition of starch or other binder unnecessary. Although an increase in drying cost for NF is expected, the new method offers a good alternative to produce specialty feed and a promising strategy to reduce water pollution issues associated with aquaculture.
Open Journal of Animal Sciences, 2012
The high temperature and pressure achieved during cooking extrusion has been shown to affect nutr... more The high temperature and pressure achieved during cooking extrusion has been shown to affect nutrient availability. To determine the effects of extrusion temperature on the efficacy of mannanoligosaccharide (Bio-Mos ®) in channel catfish, 4 experimental diets were fed for 9 wks and then challenged with Edwardsiella ictaluri bacterium. Catfish (9.9 ± 0.4 g) were randomly assigned to the following treatments: Low-None (low temperature process without additive); High-None (high temperature process without additive); Low-Bio (low temperature process with 4 g/kg diet Bio-Mos ®); High-Bio (high temperature process with 4 g/kg diet Bio-Mos ®). Although specific growth rate and food conversion ratio were similar among treatments (P > 0.10), survival after E. ictaluri challenge was highest (P < 0.01) for the fish fed Low-Bio. Increasing the extrusion temperature of the Bio-Mos ®-laden feed resulted in survival numbers similar to diets without Bio-Mos ®. Extruding catfish diets supplemented with Bio-Mos ® at lower temperatures may provide another strategy to control enteric septicemia of catfish.
Aquaculture Research, Oct 13, 2022
Journal of Applied Aquaculture, Oct 2, 2013
A 16-week feeding trial was conducted with juvenile Atlantic salmon (123 g/fish initial weight) t... more A 16-week feeding trial was conducted with juvenile Atlantic salmon (123 g/fish initial weight) to determine the effects of adding either 11% or 22% barley protein concentrate (BPC) to the diet compared to salmon fed a reference diet (0% BPC) containing mostly fishmeal. The fish were stocked into twelve 0.264 m3 tanks, providing 40 fish per tank with an average density of 18.55 kg/m3. Temperature was maintained at ˜12°C and salinity at ˜2 ppt using ground water during the study. There were no significant differences in specific growth rate (0.62 basal, 0.60 11% BPC, 0.72 22% BPC), feed conversion (1.06, 1.37, 1.09), weight gain (124.3 g, 113.5 g, 155.3 g), proximate composition of the salmon for lipid (8.4%, 7.8%, 9.8%), protein (17.3%, 17.1%, 18.6%), moisture (71.4%, 72.3%, 69.4%), and ash (6.5%, 6.1%, 6.9%) among any of the treatment groups. Salmon fed the diet containing 22% barley protein concentrate, however, had significantly greater energy retention (34%) compared to the fish fed the other diets (23%–28%). The results of this study indicate that barley protein concentrate is an acceptable feed ingredient for Atlantic salmon that should provide performance similar to fishmeal at inclusion rates below 22%.
Aquaculture Research, Oct 7, 2020
The growth of aquaculture and the global consumption of farmed fish have been steadily increasing... more The growth of aquaculture and the global consumption of farmed fish have been steadily increasing over the last decade (FAO, 2020). With this growth in global aquaculture, there is an increase in the demand for aquafeeds, which have traditionally relied on the inclusion of marine ingredients, fish meal and fish oil. Both fish meal and fish oil are sourced from wild fisheries and are used to supply essential nutrients which include n-3 long-chain polyunsaturated fatty acids (LC-PUFA), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). As the aquaculture industry has grown and the increase in demand for marine-based ingredients has risen, the identification of alternatives to fish meal and fish oil has become more important. Both fish and plant oils contain n-3 LC-PUFAs but while terrestrial plants are high in alpha linolenic acid (ALA), they are very low in EPA and DHA. Most marine finfish species along with humans are unable to convert ALA into beneficial levels of EPA and DHA, which means it must be added in the diet (Tocher, 2015). The increased use of vegetable oil as a replacement of fish oil has resulted in the decline of beneficial n-3 LC-PUFAs and the need for other sources of these essential nutri
Journal of Fish and Wildlife Management, Sep 1, 2019
There is a growing demand within research and conservation hatcheries to rear fish that more clos... more There is a growing demand within research and conservation hatcheries to rear fish that more closely approximate the smaller size and leaner body composition of their wild counterparts. Low-lipid diets may help achieve this goal as they can provide all the nutritional needs of young fish and can lead to slower growth and leaner bodies. We compared growth of Chinook Salmon Oncorhynchus tshawytscha fed three experimental low-lipid diets (11-12, 8-9, 4-6% lipid) at the onset of feeding with a commercially available high-lipid diet (18-20%) and an experimentally formulated highlipid control (13.9% lipid). After 5 mo on their respective treatments, the size, growth rate, and daily growth index of fish on the commercial diet were significantly higher than those on the three low-lipid diets. We also compared wholebody lipid content across our five diet treatments. Whole-body lipid content was significantly different across the five diets, with fish fed the commercial diet having, on average, an almost twofold higher lipid content over fish fed the lowest lipid diet formulation. We present comparable data from a limited sample of wild juvenile conspecifics as observations. We suggest that low-lipid starter diets can be used to produce healthy fish that more likely emulate some of the variations in size and body composition of wild fish.
Journal of the World Aquaculture Society, Jul 16, 2017
Juvenile rainbow trout were fed a plant-based diet supplemented with inorganic Mn added at 0, 0.5... more Juvenile rainbow trout were fed a plant-based diet supplemented with inorganic Mn added at 0, 0.5, 1, 2, 4, 8, 16, or 32 mg/kg diet for 12 wk. Whole-body Mn concentrations increased with increasing dietary levels. Rainbow trout fed 2-8 mg Mn/kg diet exhibited weight gain that was significantly higher than fish fed 0, 0.5, 1, 16, and 32 mg Mn/kg diet. Feed conversion ratio (FCR) showed a similar trend, where FCR values decreased with increasing dietary Mn until concentrations reached 8 mg Mn/kg, after which they increased. A rational nonlinear model (R 2 = 0.84) fit to weight-gain data showed that the optimal predicted supplementation level for Mn was 4.8 mg/kg diet. The optimal predicted supplementation level for Mn was similar for FCR (5 mg Mn/kg diet). The predicted 5 mg/kg diet of supplemental Mn required for the plant-based diet formulation examined in this study is lower than the National Research Council-recommended supplementation level of 12 mg/kg. However, due to potential differences in bioavailability or retention of Mn among plant-protein sources, the level of dietary supplementation for optimal growth could be slightly higher or lower depending on the dietary formulation.
Aquaculture Nutrition, Feb 22, 2017
A 12-week trial was performed with rainbow trout (Oncorhynchus mykiss) utilizing combinations of ... more A 12-week trial was performed with rainbow trout (Oncorhynchus mykiss) utilizing combinations of ingredients at two nutrient targets. Ingredient combinations were fishmeal-based diet (FMD), animal product-based diet (APD), plant product-based diet (PPD), novel plant-based diet (NPD) and potential future plant-based diet (FPD). Two nutrient concentrations were targeted: 1) to meet published amino acid targets for rainbow trout utilizing approximately 450 g/kg crude protein (400-420 g/kg digestible protein) and 2) to meet the amino acid targets based on ideal amino acid balance of trout muscle for Lys, Met and Thr utilizing approximately 400 g/kg crude protein (370-380 g/kg digestible protein). Interactive effects between ingredient combination and nutrient concentration occurred across all response variables. When diets were formulated to Target 1, fish consuming FMD and APD displayed better weight gain and feed conversion ratio (FCR) than plant-based diet, while graded effects were found within the plant-based treatments. When differing ingredient combinations were utilized and formulated to Target 2, fish grew equally well except for the NPD treatment which supported lower growth and higher FCR. Based on the data from the current experiment, one can completely remove fishmeal from trout feeds and reduce protein levels when dietary digestible amino acids are balanced.
水産総合研究センター研究報告, Oct 1, 2010
한국수산과학회 양식분과 학술대회, May 1, 2015
Uploads
Papers by Frederic Barrows