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Sablefish, Anoplopoma fimbria (also called black cod), is a long‐lived marine species with wide distribution extending from Baja California to Alaska, the Bering Sea, and through to the eastern coast of Japan. The landed weight of sablefish in the U.S. commercial fisheries is not large compared with other species; however, the exceptional value of sablefish has ranked it high compared with other species such as pollock, sockeye salmon, and Pacific cod. Sablefish are high in omega‐3 fatty acids and have white firm flesh with superior quality and taste. Current population levels are lower relative to historic ones and harvests have decreased within the last decade. The exceptional value of sablefish and decreases in wild populations have stimulated the development of methods to commercially aquaculture this species. Over the last 20 years, significant progress has been made in addressing the production of sablefish, and while there is still research that needs to be completed, sablefish have been commercially aquacultured by a small number of Canadian companies. In the Pacific Northwest, it is relatively easy to collect sablefish broodstocks from the wild and to transition them to land‐based rearing facilities. However, they must be maintained at cold temperatures to successfully reproduce. Captive broodstocks for genetic selection are not commercially available, though producers have begun their own development. Incubation conditions for yolk‐sac larvae have been developed and currently require long incubation periods at low temperatures, elevated salinity, and light exclusion. Although incubation times are long, they do not require very much attention during this phase. Exogenously feeding larvae currently require a regimen of rotifers and Artemia prior to dry feed habituation. However, tank characteristics, water turbidity, temperature, and illumination, as well as live feed enrichments have been studied. With the research that has been accomplished so far, survival rates of 10–40% have been routinely obtained at the larval stage. Despite a scarcity of species‐specific nutritional studies, researchers have shown that sablefish can be successfully cultured from the juvenile to the adult stage on commercial salmon feeds. Off‐the‐shelf salmon feeds have been used successfully in net‐pen grow‐out trials and are used by commercial producers. In addition, sablefish have proven to be a good cold‐water marine model for alternative feeds research. Still, research is needed to optimize nutritional requirements for all life stages of sablefish, develop practical feeds with these nutrient profiles, optimize feeding schedules, and produce life‐stage specific diets since the growth of sablefish differs according to size—most likely reflective of their complex life history. Sexually dimorphic growth in sablefish occurs during the typical grow‐out period, affecting time to harvest, the proportion of undersized (male) fish, and thus overall economic return to the producer. Production of all‐female monosex offspring at semi‐commercial scale using F‐1 progeny of neomales (XX males) generated through dietary treatment with 17α‐methyltestosterone is now possible. Results of long‐term feeding trials suggest that time to harvest at 2.5 kg from stocking at 75 g may be reduced by almost 3 months when monosex stocks are used. Econometric models reveal that internal rates of return are 11–15% higher for monosex relative to mix‐sex stocks over a 10‐year period under typical cage culture conditions. Sablefish are susceptible to diseases (furunculosis and vibriosis) brought on by atypical Aeromonas salmonicida and Vibrio anguillarum. Vaccination of sablefish using commercial vaccines to A. salmonicida (typical and atypical) has demonstrated that fish can be protected against a subsequent challenge by A. salmonicida, but this has only been effective by injection of the vaccine (not immersion) and how long the protection lasts has not been studied. More research is required to develop more effective vaccines, methods for vaccine delivery, and to understand conditions (ontogenetic and environmental) that may promote or enhance pathogenesis. [ABSTRACT FROM AUTHOR]

Turkish Towel Chondracanthus exasperates and taurine were added to alternative plant‐based feeds for juvenile sablefish Anoplopoma fimbria to evaluate the effect of these ingredients, alone or combined, on fish growth, feed intake and efficiency, whole body nutrient composition, and liver histomorphology. Fish growth was significantly increased with the addition of taurine, and to a lesser extent, Turkish Towel to the experimental feeds. Feed efficiency and protein retention were significantly improved with the addition of taurine, but were unaffected by Turkish Towel addition. As expected, whole body taurine content was significantly affected by taurine addition. Increases in whole body lipid were observed with both taurine and Turkish Towel addition, with a significant interaction between the two factors. Liver histomorphology was generally normal; however, histopathologic changes were observed in some fish at the end of the experiment. The occurrence of hepatocellular nuclear pleomorphism and clear cell foci was less among fish that had received the Turkish Towel feeds. The addition of taurine had no effect on the number of fish with a histopathologic change. Overall, results from this study reaffirm taurine supplementation is beneficial to sablefish receiving plant‐based feeds and indicate Turkish Towel may be a promising feed ingredient for this species. [ABSTRACT FROM AUTHOR]

To quantify the efficacy and cost of different soya protein ingredients, heated soya beans (HSB) and underprocessed (SB) full‐fat soya beans (FFSB), soya protein concentrate (SPC) and trim waste from Pacific whiting (Merluccius productus) were incorporated into feeds for the cold water marine sablefish (Anoplopoma fimbria). Feed ingredients for this study were processed using an experimental heated ball mill with demonstrated potential as an affordable process for rural or small‐scale feed production. The three feed treatments were formulated with equal amounts of soya protein and Pacific whiting process trim. The three feed treatments contained 46% protein and 18% lipid as dry matter. Three 480‐L tanks of 10 fish were used to evaluate each of the three feed treatments. Fish were fed to satiation every 2 days for 8 weeks. Weight gain of the treatment groups ranged between 56% and 105% over the course of the study. Fish growth was significantly better among fish receiving the feeds containing HSB and SPC than a feed containing SB. At the conclusion of the study, histomorphologic evaluations of the distal intestines of final fish were conducted. Varying levels of inflammation were measured for all three treatments. Fisher's exact test showed a significant reduction in mononuclear cell infiltration among fish fed heat‐treated full‐fat soya beans vs those receiving underprocessed full‐fat soya beans. Fish receiving HSB feed had significantly lower intestinal inflammation than SB fish. Based on our results, cost savings of $ 0.253/kg were calculated for the HSB feed over the SPC feed. [ABSTRACT FROM AUTHOR]

Research indicated that informal interaction among principals in an urban school district took place through verbal means in dyads and triads rather than in larger groups, and suggested patterns of upward mobility from teaching to the principalship. Findings were compared with results of a similar study in a suburban district. (Author/MJL)

As global urban population increases and large cities densify, building departments and developers worldwide are looking to the structural engineering profession to develop ideas that allow vertical construction above transportation infrastructure and maximize the use of valuable real estate in the hearts of city centers. One Manhattan West (1MW) is a supertall building recently designed and engineered by Skidmore, Owings and Merrill (SOM). The tower rises above the underground train tracks approaching Pennsylvania Station in midtown Manhattan, New York City. The structural system of the tower consists of a central reinforced concrete core and a perimeter steel moment frame. The proximity of the train tracks prevents the perimeter columns of the 70-story building from coming down vertically and be directly supported on foundations. The primary challenge to the design team was to convert this limitation into an opportunity creating a column-free lobby at the base of a 304-m tall tower. Sloping back of the perimeter columns to the central core at the base not only addresses this challenge, it also gives 1MW the unique distinction as one of the slenderest structures in New York City. Innovative structural engineering design coupled with "out-of-the-box" project delivery method, developed and implemented by SOM, has made 1MW a reality. [ABSTRACT FROM AUTHOR]

Turkish towel (Chondracanthus exasperatus), Pacific dulse (Palmaria mollis, also known as Red ribbon seaweed), and sea lettuce (Ulva spp.) were cultivated in a land-based intensive culture system at the Manchester Research Station, USA from August 2013 to September 2014. Macroalgae were grown in tumble-aerated tanks, harvested bimonthly for seasonal growth calculations, and analyzed for protein, lipid, ash, and amino acid content. Growth rate of all three species exhibited a similar pattern, with the highest specific growth rates occurring during the summer months (Turkish towel: 7.8%, Pacific dulse: 8.2%, and sea lettuce: 6.2%). Growth of all three species was lowest around winter solstice; with negative growth only observed in sea lettuce. On a dry weight basis significant differences in protein content existed between the three species with highest values for sea lettuce (29.5 ± 1.4%). Lipid content varied between species (0.95-2.78%) with significantly higher lipid observed in sea lettuce (0.58-4.82%). No significant differences were detected on a seasonal basis among each species. Essential amino acids accounted for 43 ± 0.9 to 47 ± 1.2% of total amino acids with Turkish towel having the highest value. Turkish towel had a significantly higher taurine level (0.82 ± 0.27) than the other macroalgae. The levels of persistent organic pollutants and heavy metals were low. The estimated annual product of the three species ranged from 50-to 70-mt dry weight ha-1 y-1, significantly higher than conventional crops. Land-based culture of these species can produce year-round harvest, consistent product quality, and low contaminant levels. [ABSTRACT FROM AUTHOR]

Female coho salmon, Oncorhynchus kisutch, were fed one of two experimental feeds containing lipids with markedly different stable 13 C isotope signatures during the late cortical alveolus, lipid droplet, and vitellogenesis stages of secondary oocyte growth. Ovarian and muscle lipids fatty acid concentrations were significantly affected by treatment during all three stages of development. Stable 13 C isotope analyses confirmed that dietary lipids were incorporated into both ovarian and muscle lipids during all three stages and revealed that ovarian lipids were more affected than muscle lipids during vitellogenesis. Arachidonic acid (ARA) was incorporated into ovarian lipids at the highest rate of all fatty acids examined with the greatest uptake observed during the cortical alveolus and lipid droplet stages of development. Docosahexaenoic acid (DHA) was incorporated into ovarian lipids at the next highest rate with the greatest uptake observed during the lipid droplet stage of development. The presence of an ovary specific, fatty acid transfer mechanism is proposed. Results from this study demonstrate the ability to greatly alter the fatty acid composition of ovarian lipids through a dietary change during secondary oocyte growth and may be of great interest to producers of farmed salmon and salmon broodstock programs. [ABSTRACT FROM AUTHOR]

Sablefish ( Anoplopoma fimbria ) is a highly desired seafood product, which encourages development of sustainable aquaculture methods for this marine fish. Conventional marine fish-based feeds provide essential nutrients including long chain fatty acids for piscivorous species such as sablefish. Alternative terrestrial ingredients could reduce fishing pressures on pelagic species that are the source of fish meal and fish oil, and improve source sustainability. Using juvenile sablefish, we compared the effects of a standard fish-based diet to two diets that contained primarily terrestrial plant ingredients with flaxseed or corn oil replacing the added fish oil. After an 8-week trial feeding period, there were striking differences attributable to diet. Fish receiving the alternative feeds had lower weight gain and shorter length than fish receiving the fish-based feed, suggesting sablefish obtained lower nutrients from the alternative feeds. Among the histological differences, the intestinal mucosa was significantly less vacuolated and the frequency of intestinal mucous cells was reduced in alternative feed fish. The most dramatic lesions were observed in the liver, where severe bile duct hyperplasia (53%, flaxseed oil diet; 33%, corn oil diet), and hepatocellular lesions (nuclear pleomorphism/megalocytosis, regeneration, hypertrophy, clear cell foci) occurred in only alternative feed fish. The hepatic and biliary lesions indicate the alternative diets may be deficient or possibly harmful to sablefish. The bacterial community structures from corn oil fish showed much less diversity than those for the other diets, and the microbiome structures from the three diets were distinctly different from each other. The intestinal microbiome for the fish-based diet included the largest number of families (68), and these fish also had the largest number of unique bacterial families (11) compared to those for corn oil (two) or flaxseed oil (one) fish. Regardless of diet, the stomach and intestinal microbiomes differed significantly from each other, and the feed microbiome differed from all gastrointestinal communities, suggesting that feed is not a significant source of gut bacterial diversity. Similar to other teleosts, the sablefish gastrointestinal microbiome is dominated by Bacteroidetes, Firmicutes, and Proteobacteria. These results suggest that diet-induced shifts in microbiome can occur relatively quickly in sablefish, but the shifts may not be sufficiently adaptive or cannot overcome nutrient deficiencies. This multidisciplinary study demonstrates the utility of histology and microbiology in characterizing dietary effects for novel aquaculture species. Statement of relevance Physiological assessments such as gastrointestinal microbiomes and histopathology can provide a near-term evaluation of the nutritional adequacy of alternative feeds, such as plant-based lipid diets for marine carnivorous finfish. This is the first examination of the microbiome of sablefish, a marine species under development for sustainable aquaculture. [ABSTRACT FROM AUTHOR]

Juvenile sablefish were fed a low taurine, basal feed with seven graded levels of supplemental taurine to determine taurine requirements for growth and feed efficiency. The basal feed was plant based, formulated primarily with soy and corn proteins with a minimal (9%) amount of fishmeal. The unsupplemented, basal feed contained 0.14% taurine. Experimental feeds were supplemented with 0, 0.25, 0.50, 1.0, 1.5, 3.0, and 6.0% taurine. Using the five parameter, saturated kinetic model (5 SKM), peak weight gain was predicted at 1.5% dietary taurine. Optimum weight gain, as defined as the region of the 5 SKM curve corresponding to at least 95% of peak, was predicted between 0.4% and 5.8% dietary taurine. Peak feed efficiency was predicted at 1.1% dietary taurine with optimum weight gain predicted between 0.4% and 4.2%. Whole body and muscle tissue protein and lipid content were not affected by taurine supplementation. Tissue taurine content increased asymptotically with increasing dietary taurine supplementation. Whole body tissue became saturated at 0.25 ± 0.02% taurine, expressed on a wet weight basis. Muscle tissue became saturated at 0.34 ± 0.02% taurine. Results from this study should increase the performance of alternative, plant based feeds formulated for sablefish and enable regulatory agencies better estimate the potential human exposure to taurine from the consumption of sablefish receiving these feeds. [ABSTRACT FROM AUTHOR]

Coho salmon Oncorhynchus kisutch are semelparous spawners with highly synchronized oocyte growth. Plasma was collected from maturing female fish and plasma lipids were quantified by lipoprotein class. Stable 13C isotopes were employed to investigate the origins of plasma lipids. Plasma lipoproteins were partitioned into the very low density ( VLDL), low density ( LDL), high density ( HDL) and very high density ( VHDL) lipoprotein classes. Lipids from all lipoprotein classes increased between the lipid droplet and early vitellogenesis stages of oocyte growth and VHDL lipids continued to increase through mid vitellogenesis ( P < 0.05). During vitellogenesis, total plasma lipid concentrations were similar to the sum of lipoprotein lipids ( P = 0.51). Plasma vitellogenin determined by an ELISA method was very well correlated with VHDL lipid during vitellogenesis ( R 2 = 0.91, n = 15). In general, the δ13C values of plasma lipids reflected that of feed (exogenous) and muscle (endogenous) lipids when feed and muscle δ13C values were similar, and were intermediate when differences existed between the two lipid sources. With one exception, the δ13C values of lipids from all lipoprotein classes within a plasma sample were similar. Results indicate that during sexual maturity, lipids from all plasma lipoprotein classes originate from a common pool of exogenous and endogenous lipids. [ABSTRACT FROM AUTHOR]

The small size and high surface area to volume ratio of larval fish feed presents challenges for nutrient retention in micro-particulate diets. A method for the accurate and rapid measurement of nutrient retention or loss from micro-particulate feed in water is needed to help develop micro-particulate feeds with good nutrient retention characteristics. The present study developed and validated an instrument method using fibre optic technology that measures protein leaching in real time. Larval fish feed particles of different sizes (100–500 μm) and formulations were measured. Under consistent experimental conditions, a feed could be assayed for the rate of mass loss and the half-life or time of 50% total soluble mass loss. The results closely approximated natural decay models with coefficients of determination ( r2) >0.95. The end result is a fast and accurate method to quantify and provide solid reference data for a feed formulation or particle size. Using this method allows different feeds to be compared and conclusions drawn for relative performance. [ABSTRACT FROM AUTHOR]

Limited information is available on digestibility of nutrients in various practical ingredients used in diets for commercially important finfish species, such as hybrid striped bass. This information is especially needed for sunshine bass, Morone chrysops × M. saxatilis, to improve least-cost diet formulations and to allow effective substitution of feedstuffs. A study was conducted with large (867 g) sunshine bass to determine the apparent digestibility coefficients (ADCs) for moisture, protein, lipid, and organic matter (OM) in a variety of ingredients in floating, extrusion-processed, diets. The practical ingredients tested were menhaden (MEN) fish meal (FM), anchovy (ANCH) FM, pet-food grade poultry by-product meal, feed-grade poultry by-product meal, dehulled soybean meal (SBM), and distiller’s dried grains with solubles (DDGS). Test diets consisted of a 70:30 mixture of reference diet to test ingredient with chromic oxide (1.0%) as the inert marker. Reference and test diet ingredients were mixed and extruded on a Wenger X85 single-screw extruder to produce floating pellets. The digestibility trials were conducted in twelve 1200-L circular tanks. Diets were randomly assigned to tanks of 30 sunshine bass and were fed once daily to satiation. Protein digestibility coefficients were significantly ( P < 0.05) different among test ingredients and ranged from 86.42% for MEN to 64.94% for DDGS. Lipid ADCs were significantly different ( P < 0.05) among test ingredients and ranged from 92.14% for MEN to 57.11% for SBM. OM ADCs were significantly different ( P < 0.05) among test ingredients and ranged from 89.41% for MEN to 16.94% for DDGS. This information will assist in the formulation of more efficient, economical diets for sunshine bass. [ABSTRACT FROM AUTHOR]

Yttrium oxide (Y2O3), ytterbium oxide (Yb2O3), lanthanum oxide (La2O3) and dysprosium oxide (Dy2O3) were evaluated as potential live feed markers for feeding and nutrition studies with fish larvae, by determining the uptake and depletion of markers over time in two trials, and quantifying ingestion of Y2O3-marked rotifers ( Branchionus plicatilis) by Atlantic cod ( Gadus morhua) in a third trial. In the first two trials, Artemia nauplii and rotifers quickly took up markers within 10 min to concentrations useful for nutrition studies (>2% dry weight). There was no significant difference ( P>0.05) among temperatures in depletion of markers (10, 15, 20 °C) with Artemia or rotifers. Depletion from rotifers was not significantly different ( P>0.05) between 5 and 20 min nor between 5 and 30 min for Artemia when marked at a concentration of 50 mg of marker per litre of seawater. In the second trial, rotifers and Artemia were marked with a higher concentration (250 mg L−1) and allowed to deplete for a longer time (90 min). In the third trial, visual estimates of Artemia consumed by Atlantic cod larvae were similar to consumption estimates determined by analysis of Y2O3-marked Artemia using inductively coupled plasma optical emission spectroscopy ( r2=0.77). [ABSTRACT FROM AUTHOR]

It is possible to make feed ingredients of different by-products and this paper evaluates some of the important nutritional properties of Alaska pollock (Theragra chalcogramma) and Pacific cod (Gadus macrocephalus). Heads, viscera, frames, and skins were obtained from processing plants, and heads and viscera from plants processing pink salmon (Oncorhynchus gorbuscha). Essential amino acid concentrations were used for calculating rat protein efficiency ratio (PER) and resulted in high values for fillet, followed by whole fish, frames and viscera, heads and skin. All by-products except salmon viscera had greater than 90% pepsin digestibility. Differences in mineral content were detected between species within a by-product and between by-products within species. Percent soluble protein of pollock and salmon by-products increased as pH increased from 5.4 to 7.1. [ABSTRACT FROM AUTHOR]

A supercritical fluid extraction (SFE) method employing carbon dioxide with an alcohol modifier was developed to determine fat content in fish feed. Fat content was determined for 14 dry extruded salmon or trout grower feeds with advertised fat contents ranging from 14% to 33% (w/w). Results with the new method were significantly higher than those obtained from Soxhlet extractions (AOCS Method Ba 3–38) with a difference in mean fat content of 1.9% (P<0.001) and were similar but significantly higher than total fat determinations by acid hydrolysis followed by organic extraction (AOAC Method 922.06) with a difference in mean fat content of 0.3% (P<0.001). Lipid extracts from the Soxhlet and the SFE methods were classified by thin layer chromatography-flame ionization detection into five lipid classes. Extracts from the SFE method contained a significantly greater amount of phospholipids (15–85%) than extracts from the Soxhlet method (P<0.001). Advantages of the SFE method over conventional fat determination methods include an increased yield of lipid, shorter analysis times and the absence of hazardous chemicals. The SFE method has the additional advantage over acid hydrolysis methods of estimating total fat content with minimal chemical damage to the lipid extract. [Copyright &y& Elsevier]

Debate over statutorily limiting auditor civil liability has implicitly assumed auditors are homogeneous in their preferences for capping liability. This study examines the preferences of auditors for limiting auditor liability and investigates reasons for the preferences. The study uses an Australian setting in which there has been a persistent debate for a decade or more over regulatory intervention in this area. The study provides a background to the debate over this issue and addresses the effects of two factors suggested by the extant literature, namely auditor size and the business risk of an auditor's client portfolio. These factors are argued to affect the expected costs of litigation facing auditors and therefore their preferences on capping liability. Using the submissions by audit firms on an Australian Companies and Securities Law Review Committee Discussion Paper on limiting auditor liability, the study finds larger audit firms that have greater capacities to lobby and greater expected costs of litigation from unlimited liability than smaller firms, dominate the respondents on the Paper and tend to be more supportive of liability limitation than smaller audit firms. Within the array of possible methods of capping liability canvassed by the Discussion Paper, the study documents evidence of diversity in preferences among audit firms. Larger audit firm size is associated with a preference for a group of methods that provides such firms with opportunities to benefit from the capping at the expense of the smaller audit firms. The method most preferred by the larger audit firms is the multiple of fee with a prescribed minimum. Perhaps not surprisingly, this is also the preferred method of the professional accounting bodies in Australia. As to the effect of the riskiness of the client portfolio on preferences for methods of limiting liability, the study finds that higher business risk in an auditor's portfolio is associated with a preference for methods that give greater control over their liability exposure. The study has implications for the impact of regulation of capping liability on competition in the audit services market. [ABSTRACT FROM AUTHOR]

This article reports that gluten, the protein component of wheat, is toxic for patients with coeliac disease. Ingestion of gluten is associated with small intestinal damage, malabsorption of nutrients and elevated serum and intestinal antibodies against these cereal antigens. The development and duration of systemic tolerance to ingested gluten were examined by manipulating the diets of the mice at various stages in their growth. These results demonstrate that the ingestion of dietary gluten renders mice hyporesponsive to parenteral immunisation with gliadin.