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Simple Summary: Our study showed that a vitamin C (VC) supplementation in grower walleye pollock diet improved growth performance and plasma superoxide dismutase activity. Also, dietary VC significantly enhanced feed utilization, body protein content, and plasma growth hormone levels. Moreover, broken-line regression analysis considering weight gain revealed that the optimal dietary VC level for grower walleye pollock was 156.42 mg kg−1 diet. The optimal dietary vitamin C (VC) levels for walleye pollock (Gadus chalcogrammus) remain undefined. This study aimed to assess the effect of dietary VC levels on the growth performance and biochemical parameters of grower walleye pollock and determine the optimal VC level for their diet. Six experimental diets (VC0, VC1, VC3, VC5, VC7, and VC10) with VC levels of 3.24, 21.92, 63.31, 101.42, 145.46, and 202.51 mg kg−1 diet, respectively, were fed to fish (initial mean weight: 173.5 ± 0.31 g) for 8 weeks. At the end of the feeding trial, fish fed the VC7 and VC10 diets exhibited significantly higher growth (final body weight, weight gain, and specific growth rate) and improved feed utilization (feed efficiency and protein efficiency ratio) compared with fish fed the VC0 diet (p < 0.05). The VC3–VC10 diets significantly reduced plasma superoxide dismutase (SOD) activity (p < 0.05). Compared with the VC0 group, fish fed the VC7 and VC10 diets showed significantly elevated growth hormone and insulin-like growth factor-1 levels in plasma (p < 0.05). In conclusion, dietary VC supplementation in walleye pollock improved growth performance and SOD activity. Moreover, broken-line analysis on weight gain indicated that the optimal dietary VC level for grower walleye pollock was approximately 156.42 mg kg−1 diet. [ABSTRACT FROM AUTHOR]

We aimed to determine the optimal conditions for the mass culture of rotifers, which can be used as feed for cold-water fish species at low temperatures. The growth and specific growth rates (SGRs) of rotifers were assessed considering water temperature, salinity, density, dissolved oxygen (DO) levels, and the amount of Chlorella supplied as feed. The growth of rotifers was higher at 15 °C than at 10 °C and at salinities of ~11–17 psu. Initial inoculation densities of 500 and 700 individuals/mL resulted in the highest rotifer density, and SGR was highest at 100 individuals/mL. DO concentration did not significantly affect the growth and SGRs of rotifers. Enrichment with fatty acids is important to supplement the diet of cold-water fish species. Highly unsaturated fatty acid content increased with enrichment time to 14.04 ± 0.86% at 12 h and 15.58 ± 2.20% at 24 h. Thus, the optimal conditions for rotifer mass culture are a water temperature of 15 °C, salinity of 11–17 psu, initial inoculation density of 300–500 individuals/mL, DO concentration of 8 mg/L or more, and Chlorella supply at 7.5 × 1012 cells/mL. Therefore, the present study suggests optimal culture conditions of rotifers at low temperatures for breeding cold-water fish species. [ABSTRACT FROM AUTHOR]

ABSTRACT A 16-wk feeding trial was conducted to assess the effects of different types of dietary carbohydrate on growth and body composition of juvenile abalone (Haliotis discus). A total of [...]

ABSTRACT Performance and stress resistance of juvenile abalone (Haliotis discus) fed formulated diets substituting fish meal (FM) and macroalgae (MA) with soybean meal and rice bran, respectively, was compared with [...]

Long noncoding RNAs (lncRNAs) are primarily regulated by their cellular localization, which is responsible for their molecular functions, including cell cycle regulation and genome rearrangements. Accurately identifying the subcellular location of lncRNAs from sequence information is crucial for a better understanding of their biological functions and mechanisms. In contrast to traditional experimental methods, bioinformatics or computational methods can be applied for the annotation of lncRNA subcellular locations in humans more effectively. In the past, several machine learning-based methods have been developed to identify lncRNA subcellular localization, but relevant work for identifying cell-specific localization of human lncRNA remains limited. In this study, we present the first application of the tree-based stacking approach, TACOS, which allows users to identify the subcellular localization of human lncRNA in 10 different cell types. Specifically, we conducted comprehensive evaluations of six tree-based classifiers with 10 different feature descriptors, using a newly constructed balanced training dataset for each cell type. Subsequently, the strengths of the AdaBoost baseline models were integrated via a stacking approach, with an appropriate tree-based classifier for the final prediction. TACOS displayed consistent performance in both the cross-validation and independent assessments compared with the other two approaches employed in this study. The user-friendly online TACOS web server can be accessed at https://balalab-skku.org/TACOS. [ABSTRACT FROM AUTHOR]

A long‐term feeding trials were conducted to evaluate the effect substituting dietary fishmeal with a mixture of plant and animal protein sources on growth, body composition and economic efficiency of young Korean rockfish (Sebastes schlegeli). A fishmeal‐based diet was designated the control (Con). Three among the other six diets, respectively, had 30%, 40% and 50% of its fishmeal replaced by a mixture of plant and animal protein sources (designated as FS30, FS40 and FS50 respectively), while the remaining three diets were FS30, FS40 and FS50 diets supplemented with L‐lysine and L‐methionine (FS30AA, FS40AA and FS50AA respectively). Three replicated groups of fish (initial body weight, 86 ± 1.9 g) were fed one of the seven diets for 30 weeks. By the end of the feeding trials, the survival rate of all experimental groups was over 92%. The final mean weight, weight gain, feed efficiency, protein efficiency ratio and condition factor of fish were not significantly affected by dietary treatments. Incidence cost of FS50 diet was significantly lower than Con diet. FS50 and FS40AA diets exhibited significantly higher profit index than the Con diet. FS40AA and FS50 diets were the best economically, followed by FS40, FS50AA, FS30, FS30AA and Con diets. These results suggest that the dietary fishmeal could be substituted with a mixture of plant and animal protein up to 50% in the diet without a reduction in growth and feed utilization of young Korean rockfish. Taking account of economic efficiency, the FS50 diet is recommendable for young Korean rockfish farming. [ABSTRACT FROM AUTHOR]

The present study examined the dietary substitution effect of chicken by‐product meal (CBM) for fish meal (FM) on growth, feed utilization, body composition, haematology and non‐specific immune responses of olive flounder, Paralichthys olivaceus. Six isonitrogenic and isolipidic experimental diets were prepared. The control (Con) diet contained 650 g/kg FM. One hundred, 200, 300, 400 and 500 g/kg FM were replaced with CBM, referred to as the CBM10, CBM20, CBM30, CBM40 and CBM50 diets, respectively. A total of 400 juvenile fish averaging 14.7 g was distributed into 20 tanks (20 fish/tank) and fed triplicate groups of each diet, except for quadruplicate groups for the Con and CBM30 diets twice daily to satiation for 8 weeks. Arginine, phenylalanine and threonine content of the experimental diets increased with dietary increased substitution of FM with CBM. The experimental diets did not affect survival, weight gain, specific growth rate, feed consumption and feed utilization of fish. The chemical composition, whole body amino acid profiles, haematological variables and non‐specific immune responses of fish were not changed by the experimental diets. These findings suggest that FM up to 500 g/kg can be substituted with CBM without retardation in growth, feed utilization, haematology and non‐specific immune responses of olive flounder. [ABSTRACT FROM AUTHOR]

The attractiveness of crude feed ingredients to olive flounder and effects of including feed ingredients showing strong feeding attractiveness in extruded pellet (EP) on performance of fish were determined. Four types of experimental EP were prepared to evaluate the effects of feed ingredient manipulation on performance of fish. Five per cent anchovy meal component of the control diet was substituted with an equal amount of jack mackerel meal, sardine meal and hydrolysed fish meal to create the JM, SM and HFM diets respectively. The diets were prepared in commercial form as EP. Jack mackerel meal produced the strongest feeding attractant responses of olive flounder, followed by sardine meal and hydrolysed fish meal. The greatest weight gain, feed consumption and condition factor (CF) were observed in fish fed the JM diet, followed by fish fed the SM, HFM and control diets, in that order in the 8‐week feeding trial. The dietary manipulation of feed ingredients performed in this study showed that the inclusion of ingredients with strong feeding attractiveness improved feed consumption and eventually accelerated the growth performance and CF of the fish. [ABSTRACT FROM AUTHOR]

The attractiveness of various protein sources of 16 feed ingredients was determined in juvenile rockfish (Sebastes schlegeli) by using reinforced acrylic tank composed of three equally divided rectangular attracting chambers and an acclimatization chamber. Thirty fish were held in the acclimatization chamber at a time and tournament comparison of feed ingredients was applied to evaluate attractiveness. Jack mackerel (JM) (40.0%), sardine (SM) (33.3%), Pollack (PM) (40.0%), shrimp (SHM) (36.7%), mussel meal (40.0%) and oyster (43.3%) meals achieved the highest feeding attractiveness to rockfish in the 1st through 6th preliminary test, respectively. JM (40.0%), SHM (36.7%), squid meal (SQM) (33.3%), SM (40.3%), PM (40.0%) and PM (36.7%) achieved the highest feeding attractiveness to fish in the 7th through 12th preliminary test, respectively. Among the top five feed ingredients showing high attractiveness to rockfish, JM achieved higher attractiveness than PM and SHM in the 1st trial. In the 2nd trial, attractiveness of JM to rockfish was higher than SM and SQM. SM achieved higher attractiveness to rockfish than SQM, but not different from PM throughout the 30-min observation in the 3rd trial. The strongest feeding attractant response of rockfish was observed in JM, followed by SM, SQM, PM, and SHM, in order among various feed ingredients. [ABSTRACT FROM AUTHOR]

Growth performance and the soft body composition of juvenile abalone fed the extruded pellets (EPs) substituting fish meal (FM) and macroalgae (MA) with tunic meal of sea squirt (SS) was investigated. A total of 1,260 abalone were distributed into 18 containers. Six experimental diets were prepared in triplicate. Five diets were pelletized by an extruder pelleter. The 140 g/kg FM and 250 g/kg mixture of MA were included into the control (Con) diet. Five hundred and 1,000 g/kg of each FM and MA were substituted with an equal amount of tunic meal of SS, referred to as the FM50, FM0, MA50 and MA0 diets, respectively. Finally, dry Undaria pinnatifida was prepared. Weight gain and specific growth rate of abalone fed all EPs were greater than those fed U. pinnatifida. Weight gain of abalone fed MA50 and FM50 diets was greater than Con and FM0 diets, but not different from MA0 diet. Higher crude protein and lipid contents were observed in soft body of abalone fed all EPs compared to U. pinnatifida. In conclusion, FM and MA up to 500 and 1,000 g/kg, respectively, could be replaced with tunic meal of SS in EPs without retardation in growth of abalone. [ABSTRACT FROM AUTHOR]

Substitution effect of Undaria pinnatifida with citrus peel by‐product (CPB) on growth, body composition and air exposure stressor of abalone was determined. A total of 1,080 abalone were distributed into 18 net cages. Five formulated diets were prepared in triplicate. The CPB0 diet contained 200 g/kg U. pinnatifida. The 250, 500, 750 and 1,000 g/kg U. pinnatifida were substituted with the equal amount of CPB, referred to as the CPB250, CPB500, CPB750 and CPB1000 diets, respectively. Finally, dry U. pinnatifida was prepared. Abalone were fed for 16 weeks and then subjected to air exposure stressor for 24 hr. The cumulative mortality of abalone was monitored for the following 4 days after 24‐hr air exposure. Survival, weight gain and specific growth rate (SGR) of abalone fed all formulated diets were greater than those of abalone fed the U. pinnatifida. The greatest weight gain and SGR were achieved in abalone fed the CPB500 diet. The chemical composition of the soft body of abalone was not affected by the experimental diets. Higher cumulative mortality was observed in abalone fed the CPB0 and dry U. pinnatifida at 16 hr after 24‐hr air exposure compared to abalone fed all other diets. In conclusion, U. pinnatifida could be completely substituted with CPB in abalone feed. [ABSTRACT FROM AUTHOR]

Genetic alterations are the starting point leading to numerous changes in clinical and pathologic features (phenotypes) of individual cancers; however, their inter‐relationships in gastric cancers (GC) are unclear. We performed massive parallel sequencing of 381 cancer‐related genes and compared the results with clinical and pathologic findings in 330 GC. High tumor mutation burden (TMB) accounted for 11% of GC (n = 37) and all 19 MSI‐H GCs were high TMB. High TMB was significantly more frequent in intestinal‐type by Lauren, tumor with higher host cellular immune response, earlier AJCC stage and favorable prognosis. The most significantly mutated genes were TP53 (54%), ARID1A (23%), CDH1 (22%), PIK3CA (12%), RNF43 (10%) and KRAS (9%). For receptor tyrosine kinases, amplifications detected by immunohistochemistry were higher than sequencing (HER2, 9.1% vs. 5.8%; EGFR, 11.2% vs. 6.1%; FGFR2, 4.6% vs. 3.9%, c‐MET, 3.4% vs. 0.9%). PTEN protein loss (22%) correlated well with underlying PTEN alterations while ATM loss (27%) was not significantly correlated with genetic alterations of ATM. p53 protein expression predicted alterations of TP53 with high sensitivity (97.8%) and low (15.9%) specificity. The poorly cohesive histology/CDH1‐mutant GC subgroup showed the worst survival (p < 0.001). PD‐L1 expression was significantly associated with MSI‐H, MLH1 loss, ATM loss, MET positivity, higher host immune response, and genetic alterations of ARID1A, BRD3, PIK3CA, KRAS, MAP3K13, CDH2, PTEN and ESR1. The merged clinical, pathology and genomics of GC provide a better understanding of GC and new insights into the treatment of GC. What's new? Genetic alterations are the starting point of numerous changes in clinical and pathologic features (phenotypes) of individual cancers; however, their interrelationships in gastric cancers (GC) remain unclear. In this study correlating clinical, pathologic, and genomics data in 330 GC patients, high tumor mutation burden (TMB) accounted for 11% of cases and was significantly more frequent in intestinal‐type GC, tumors with higher host immune response, earlier cancer stage, and favorable prognosis. PD‐L1 expression was significantly associated with MSI‐H, higher host immune response, and high TMB. The results provide a better understanding of GC and serve as a baseline for precision oncology. [ABSTRACT FROM AUTHOR]

The dietary substitution effect of fishmeal (FM) with tunic meal of sea squirt (SS) on growth and body composition of juvenile abalone, Haliotis discus, was evaluated. A total of 1470 juvenile abalone were distributed into 21 70‐L plastic rectangular containers. Six experimental diets in triplicate were prepared, and 20% FM was included in the FM0 diet. The treatments consisted of 20, 40, 60, 80, and 100% of FM substituted with tunic meal of SS, referred to as the FM20, FM40, FM60, FM80, and FM100 diets, respectively. Undaria was also prepared to compare the effect of the formulated diets on performance of abalone. The experimental diets were fed to abalone once a day at a satiation level for 16 wk. Weight gain of abalone fed the FM0 diet was higher than that of abalone fed the FM100 diet and Undaria, but not different from that of abalone fed the FM80 diet. Crude protein, crude lipid, and ash contents of the soft body of abalone fed all formulated diets were higher than those of abalone fed the Undaria diet. In conclusion, FM up to 80% could be replaced with tunic meal of SS without retardation in growth of abalone. The best growth was obtained in abalone fed the FM20 diet. [ABSTRACT FROM AUTHOR]

This paper presents the design of cryogenic induction motor submerged in liquefied natural gas (LNG) for operating LNG spray pump. In cryogenic environment of −163 °C, the torque characteristics of induction motor differ greatly from the operating conditions at room temperature. So, in order to obtain the operating characteristics corresponded with design specifications of the induction motor in cryogenic environment, it is necessary to redesign motor dimensions from the result of conventional design by reflecting the changes of material properties under the very low temperature (VLT). This paper focused on the design of cryogenic induction motor considering the variation of resistivity for the stator windings and rotor bars. Also, the distribution of magnetic flux density and magnetic saturation effect on the steel core are analyzed by using 2-D finite-element method for ac sinusoidal time varying excitations under the VLT. The result of proposed method considered the magnetic and electric characteristics of matters in VLT successfully, so that the motor performances at the cryogenic temperature fit well with expected. The designed motor was fabricated and torque performance measured in VLT agreed well with design goals. [ABSTRACT FROM AUTHOR]

In addition to the rapid advancement in Next-Generation Sequencing (NGS) technology, clinical panel sequencing is being used increasingly in clinical studies and tests. However, tools that are used in NGS data analysis have not been comparatively evaluated in performance for panel sequencing. This study aimed to evaluate the tools used in the alignment process, the first procedure in bioinformatics analysis, by comparing tools that have been widely used with ones that have been introduced recently. With the accumulated panel sequencing data, detected variant lists were cataloged and inserted into simulated reads produced from the reference genome (h19). The amount of unmapped reads and misaligned reads, mapping quality distribution, and runtime were measured as standards for comparison. As the most widely used tools, Bowtie2 and BWA–MEM each showed explicit performance with AUC of 0.9984 and 0.9970 respectively. Kart, maintaining superior runtime and less number of misaligned read, also similarly possessed high level of AUC (0.9723). Such selection and optimization method of tools appropriate for panel sequencing can be utilized for fields requiring error minimization, such as clinical application and liquid biopsy studies. [ABSTRACT FROM AUTHOR]

This study deduces numerical and simulation‐aided approaches of quality factor affected by intense beam loading in the input cavity. Intense relativistic electron beam loading based on the model of electron density distribution is applied to analyse the particle‐microwave interaction. The expression for gap voltage difference in the input cavity between without beam‐loading and with it is derived to find out the beam‐loaded quality factor. The simulated data by decaying time method of particle‐in‐cell code being in a good agreement with that attained by the numerical approach are presented. Those presented approaches will be particularly available for a relativistic klystron amplifier with relatively low quality factor and intense relativistic electron beam in the input cavity. [ABSTRACT FROM AUTHOR]

The effects on growth and body composition that result from tuna byproduct meal ( TBM) substituted for fish meal in the diet of juvenile abalone, Haliotis discus, were determined. One thousand two hundred sixty juvenile abalone were randomly distributed into 18 70-L plastic rectangular containers. Six experimental diets were prepared in triplicate. The TBM0 diet included 28% fish meal and 13% soybean meal as the protein source. Twenty-five, 50, 75, and 100% of the fish meal were substituted with TBM. Finally, salted sea tangle was prepared. The essential amino acids, such as isoleucine, lysine, and valine, tended to decrease with the dietary substitution of TBM for fish meal in the experimental diets. The weight gain and specific growth rate ( SGR) of abalone that were fed the TBM25 diet were higher than those of abalone that were fed the other diets. The crude protein content of the soft body of the abalone linearly decreased with the dietary substitution of TBM for fish meal. In conclusion, as much as 75% of the fish meal in the diet of abalone can be replaced with TBM without retardation in weight gain and SGR of the abalone when 28% fish meal was included. [ABSTRACT FROM AUTHOR]

Many approaches exist for energy storage and delivery to the load, including high-power relativistic applications. One of the best solutions for the driver of high-power relativistic applications is the Marx generator. This paper describes the design, fabrication, and experimental validation of a Marx generator consisting of capacitors, spark-gap switches, and resistors. It is designed as an eight-stage Marx circuit to reach an output voltage level as low as −500 kV, and it is directly connected to the Blumlein pulse-forming line (PFL) to achieve more than 100 ns of the full-width at half-maximum. Experiments are performed with a solution load in a manner similar to having a coaxial structure in a high vacuum with a pressure of below 0.5\, \times \, 10^-5 torr, to prevent breakdown and measure the amplitude of the negative high-voltage pulse waveform. The solution load is designed to capture the short-pulse output of the PFL with a rise time of less than 25 ns and a voltage level of approximately −500 kV. The experimental results show that the output pulse can be used as a source to generate an intense relativistic electron beam at the gun for high-power relativistic applications. [ABSTRACT FROM PUBLISHER]

Thermal analysis of an L-band 60-kW (continuous-wave) double-ring strapped magnetron for optimizing the design of a cathode support structure and cooling system is presented. This magnetron consists of an oxygen-free copper anode with ten built-in cooling channels and a directly heated tungsten cathode. The operating temperature of the cathode is greater than 2000 ^\circ\C; therefore, proper thermal design of the cathode support structure is essential for reliable operation. The heat convection coefficient for the forced air is estimated by simulations comparing the simulated temperatures for different heat convection coefficients with the measured one. It is observed that the comparison between simulations with measurement is in good agreement for various temperatures from 1000 ^\circ\C to 2000 ^\circ\C when the estimated heat convection coefficient of the forced air is used. [ABSTRACT FROM AUTHOR]

We report the fabrication of stretchable transparent electrode films (STEF) using 15-nm-diameter Ag nanowires networks embedded into a cross-linked polydimethylsiloxane elastomer. 15-nm-diameter Ag NWs with a high aspect ratio (˃1000) were synthesized through pressure-induced polyol synthesis in the presence of AgCl particles with KBr. These Ag NW network-based STEF exhibited considerably low haze values (<1.5%) with a transparency of 90% despite the low sheet resistance of 20 Ω/sq. The STEF exhibited an outstanding mechanical elasticity of up to 20% and no visible change occurred in the sheet resistance after 100 cycles at a stretching-release test of 20%. [ABSTRACT FROM AUTHOR]

Highly stable and durable conductive silver nanowire (Ag NW) network electrode films were prepared through decoration with a 5-nm-thick Ti layer. The Ag NW network 2-D films showed sheet resistance values as low as 32 ohm/sq at 88% transparency when decorated with Ti. These 2-D films exhibited a 30% increase in electrical conductivity while maintaining good stability of the films through enhanced resistance to moisture and oxygen penetration as a result of the protective effect of the Ti layer. [ABSTRACT FROM AUTHOR]

Long silver nanowires (Ag NWs) with lengths of ∼65 μm and aspect ratios as high as 1500 were synthesized using a tetrabutylammonium dichlorobromide (TBADCB) salt-based polyol process. The kinetics of crystal growth was studied using stepwise scanning electron microscopy, X-ray diffraction, and surface Plasmon resonance spectroscopy. The diameters of the Ag NWs were shown to be strongly dependent on the molar concentration of TBADCB/AgNO3. We further demonstrated that the length of the Ag NWs could be controlled by adjusting the reaction temperature at the nucleation step or by varying the stirring speed. NWs with lengths of up to 60 μm and diameters as large as 32 nm were obtained when unidirectional axial stirring was performed at 1000 rpm using a T-shaped impeller, and at an initial nucleation temperature of 20°C. The obtained two-dimensional conducive Ag NW network films exhibited good optical properties, with a low haze of ≤1.0% and 98% transmittance at 60 Ω/sq, similar to the properties of the films compared of 20-nm-diameter Ag NWs (aspect ratio: ∼1000). [ABSTRACT FROM AUTHOR]

Abstract Highly stretchable, flexible, and transparent electrode films were fabricated based on a composite of silver nanowire (Ag NW) networks hybridized with single-walled carbon nanotubes (SWCNTs) in a sandwich structure, wherein a Ag NW-SWCNT hybrid network electrode was embedded between layers of polydimethylsiloxane and transparent polyurethane films. When 0.025 wt% SWCNTs were hybridized with Ag NWs, a Ag NW-SWCNT network electrode, which had excellent optical properties (very low haze value of less than 1% and 95% transmittance) and a low sheet resistance value of 30 Ω/sq, was obtained through the effective electrical transportation of the NW–NW, CNT–NW, and CNT–CNT junctions. The fabricated film heaters showed environmental endurance, and no significant performance degradation was observed after the films were kept at a high temperature of 85 °C and humidity of 85%. They also exhibited high stretchability up to 20%. Effective Joule heating can increase the temperature of the electrode films (30 Ω/sq) up to 68 °C at a bias of 11 V. [ABSTRACT FROM AUTHOR]

Effect of dietary substitution of Undaria pinnatifida with onion extract by-product (OEB) on growth, body composition and air exposure stress of juvenile abalone was determined. One thousand and eighty juvenile abalone were randomly distributed into 18,100 L net cages (sixty per cage). Five formulated diets were prepared. Twenty percent U. pinnatifida was included into the control (Con) diet. Twenty five, 50, 75 and 100% U. pinnatifida were substituted with an equal amount of OEB, referred to as the OEB25, OEB50, OEB75 and OEB100 diets, respectively. Finally, dry U. pinnatifida was prepared to compare formulated diets on growth performance of abalone, referred to as the Undaria. Each diet were randomly assigned to triplicate groups of abalone and fed to abalone once a day to satiety with little leftover for 16 weeks. After the 16-week feeding trial, abalone were subjected to air exposure for 24 h and survival was monitored for the next 4 days. Weight gain and specific growth rate (SGR) of abalone fed all formulated diets were greater than those of abalone fed the Undaria. The greatest weight gain and SGR were obtained in abalone fed the OEB50 diet, followed by the OEB75, OEB25, Con and OEB100 diets, in that order. Weight gain and SGR of abalone fed the OEB100 diet were lower than those of abalone fed the Con diet. Shell length, width and height and soft body weight of abalone tended to agree with growth rate of abalone. No difference in the chemical composition of the soft body of abalone was observed. The survival of abalone fed the OEB25, OEB50, OEB75 and OEB100 diets was higher than that of abalone fed the Undaria and Con diet at the end of 4-day post observation after 24-h air exposure. In conclusion, U. pinnatifida up to 75% could be replaced with OEB in abalone feed when 20% U. pinnatifida was included. The greatest growth performance was obtained in abalone fed the OEB50 diet. • Dietary substitution effect of various levels of Undaria pinnatifida with onion extract by-product (OEB) on growth, body composition and air exposure stress of juvenile abalone was compared to abalone fed dry U. pinnatifida. • After the 16-week feeding trial, abalone were subjected to air exposure for 24 h, and then cumulative mortality was monitored for the next 4 days. [ABSTRACT FROM AUTHOR]