Seriola Quinqueradiata Research Articles

Effect of two full-fat insect meals, yellow mealworm and black soldier fly larva, on growth performance of juvenile yellowtail

Abstract Given the expanding demand for fish meal (FM) worldwide, insect meal has become a promising alternative to FM for sustainable aquaculture. Yellowtail (Seriola quinqueradiata), the predominant farmed fish in Japan, is a carnivorous marine species that requires a substantial quantity of FM in its diet. Two feeding trials were conducted with the aim of assessing the applicability of two full-fat insect meals, yellow mealworm (Tenebrio molitor) meal (TM) and black soldier fly (Hermetia illucens) larvae meal (HI), as FM substitutes in for juvenile yellowtail. In the first trial, replacing 24.3% of FM with TM resulted in a final fish weight of 137.4 ± 40.1 g (mean ± SD as also indicated for subsequent values), comparable to the control group with a weight of 139.5 ± 44.0 g, while maintaining an equivalent level of n-3 fatty acid content across all diets used in the trial. The body weight of fish fed a diet containing HI, at 121.2 ± 31.0 g, was significantly lower than the control group, whereas the difference between fish fed a diet containing TM was not statistically significant. According to the growth analysis, dietary inclusion of TM was more suitable than that of HI, prompting a second trial to evaluate the maximum limit of FM substitution with TM without adjusting fatty acid profiles across diets. In the subsequent trial, fish growth exhibited a clear decrease trend with the inclusion rate of TM. These findings suggest that, while the substitution of FM with HI and TM has been shown to be feasible under equivalent fatty acid profiles in diets, the imbalanced fatty acid profile resulting from the inclusion of full-fat insects could be attributed to a deficiency in n-3 fatty acids, leading to the observed growth retardation in juvenile yellowtail.

Changes in the Quality and Microflora of Yellowtail Seriola quinqueradiata Muscles during Cold Storage.

We evaluated the changes in the quality and microflora of yellowtail flesh cold-stored until spoilage. Based on the sensory evaluation, odor palatability was deemed unacceptable for dark muscle (DM) and the dorsal part of the ordinary muscle (OD) after >10 days and 14 of storage, respectively. Log 7 CFU/g in DM as well as OD was obtained on days 10 (Aeromonas spp.) and 14 (Enterobacteriaceae and Pseudomonas spp.) of storage, whereas log 5 (Brocothrix thermosphacta) and 6 (H2S-producing bacteria) CFU/g in them were obtained on day 14 of storage. In these bacteria, the viable bacterial counts of Pseudomonas spp. and Aeromonas spp. in DM were significantly higher than those in OD only at some storage times. Amplicon sequencing revealed that in both muscles, Pseudomonas became predominant after storage, with greater than 90% recorded after more than 10 days of storage. The relative abundances of Acinetobacter, Unclassified Gammaproteobacter, and Shewanella were relatively high in both muscles after more than 10 days of storage; however, these values were less than 5%. Ethyl butyrate in the OD and DM and 2,3-butanedione in the OD were first detected on days 14 and 10 of storage, respectively. Acetoin in the OD increased by 81-fold after 14 days of storage and was significantly increased in the DM after more than 10 days compared with the amount detected pre-storage. Volatiles, such as (E)-2-pentenal in the OD and 1-pentanol in the DM, decreased and increased linearly, respectively, throughout the 14-day storage period. Altogether, these volatile components may cause quality deterioration due to spoilage and/or lipid oxidation during cold storage of the OD and DM.

Effects of installation depth and recording start time on fish count and mean fork length of <i>Seriola quinqueradiata</i> measured by optical stereo cameras

Effects of installation depth and recording start time on fish count and mean fork length of <i>Seriola quinqueradiata</i> measured by optical stereo cameras

Horizontal and vertical movement patterns of yellowtail (Seriola quinqueradiata) in the East Sea of Korea

Horizontal and vertical movement patterns of yellowtail (Seriola quinqueradiata) in the East Sea of Korea

Dynamics of serum IgM level during the growth of juvenile Japanese amberjack Seriola quinqueradiata

Dynamics of serum IgM level during the growth of juvenile Japanese amberjack Seriola quinqueradiata

Extracellular Vesicles Derived from the Serum of Seriola quinqueradiata Induce Human Umbilical Vein Endothelial Cell Proliferation through Angiogenic Signaling.

Daily intake of extracellular vesicles (EVs) derived from fish (f-EVs) may contribute to health maintenance by reducing cardiovascular risk. However, their physicochemical and biological properties remain unclear. In this study, we compared the physical characteristics (size, zeta potential, and free fatty acid composition) and biological characteristics (cell proliferation) of f-EVs with those of EVs derived from mammals (m-EVs). In the physical characteristic analysis, f-EVs derived from Pagrus major (PMS-EVs) and Seriola quinqueradiata (SQS-EVs) had a negatively charged and a positively charged group and higher levels of unsaturated fatty acids, unlike m-EVs. In the biological characteristic analysis for f-EVs, SQS-EV enhanced the human umbilical vein endothelial cell proliferation via vascular endothelial growth factor receptor 2, fibroblast growth factor receptor 1, or platelet-derived growth factor β. These data suggest that SQS-EVs have unique functions compared with other EVs. To the best of our knowledge, this is the first study to show that SQS-EVs act positively on human cells.

Effects of heating duration on the digestibility of fish protein powders at 99 °C in vitro using yellowtail Seriola quinqueradiata digestive enzymes

Effects of heating duration on the digestibility of fish protein powders at 99 °C in vitro using yellowtail Seriola quinqueradiata digestive enzymes

Antimicrobial use in ecolabel certified and non-certified yellowtail (Seriola quinqueradiata) aquaculture in Japan

Given the emergence of antimicrobial-resistant pathogens in aquaculture worldwide, overuse of antimicrobials must be avoided to enhance sustainability in aquaculture. Although the actual usage of antimicrobials has been disclosed in some cultured species, such as salmon, this information is not always available for other species. In this study, with the cooperation of yellowtail farms in Japan, the actual usage of antimicrobials for commercially cultured yellowtail was investigated. In a survey of 28 net pens of cultured yellowtail, an average of 0.95 g (95 % confidence interval 0.78–1.11) of total antimicrobials was used per kilogram of cultured yellowtail. Each of the antimicrobials is listed as a critically or a highly important antimicrobial by the World Health Organization. A comparison of fish cultured according to the sustainability standard established by the Aquaculture Stewardship Council (ASC) with those not cultured according to the standard showed that the total quantity of antimicrobials used was significantly lower for the former than for the latter. However, the quantity of antimicrobial use even for ASC-certified yellowtail was still higher than that for other cultured species. Therefore, further and sustained efforts to reduce antimicrobial use are needed.

Evaluation of the in vivo and in vitro interleukin-12 p40 and p35 subunit response in yellowtail (Seriola quinqueradiata) to heat-killed Lactobacillus plantarum strain L-137 (HK L-137) supplementation, and immersion challenge with Lactococcus garvieae

Dietary supplementation of immunostimulants might be effective to reduce the economic losses due to infectious diseases and the use of antibiotics in aquaculture. To investigate the immune response of interleukin-12 (IL-12) in yellowtail Seriola quinqueradiata to heat-killed Lactobacillus plantarum strain L-137 (HK L-137), we performed a leukocyte culture, feeding trial with diets containing L-137 and an immersion challenge with Lactococcus garvieae. IL-12 (IL-12p70) is a heterodimeric cytokine composed of IL-12p35 and IL-12p40 subunits. In the yellowtail-leukocyte culture, HK L-137 treatment stimulated the mRNA expression of one IL12p35 subunit (p35a) and all IL12p40 subunits (p40a, p40b, and p40c) in a dose-dependent manner. Furthermore, mRNA expression of type-I helper (Th-1) cytokine (tumor necrosis factor α, TNF-α, and interferon γ, IFN-γ) was also stimulated by HK L-137. After 6 weeks of feeding yellowtails with diets containing 0, 20, and 100 ppm of HK L-137, the mRNA expression of p35a and p40b in the spleen leukocytes increased with the dietary concentration of HK L-137, and that of p40b, p40c, and ifng in the head kidney leukocytes were the highest in the 20 ppm HK L-137 group. Survival rates in the 20 ppm HK L-137 group after immersion challenge with L. garvieae were significantly higher than the control (0 ppm of HK L-137). The 100 ppm HK L-137 group did not significantly suppress mortality. HK L-137 showed immunostimulant activity by increasing the expression of il-12, tnfa, and ifng mRNA in both in vitro and in vivo tests in yellowtail. Our results suggest that dietary supplementation with 20 ppm HK L-137 is the most efficient dose for improving immunity in yellowtail. Furthermore, a high dose of HK L-137 and/or long-term feeding of a diet containing HK L-137 might suppress the immune response, which probably decreases the survival rate of fish. To maintain a high immune response in yellowtail, the optimal dietary concentration of HK L-137 and/or feeding regime should be investigated further.

Comparative genome analyses of three serotypes of Lactococcus bacteria isolated from diseased cultured striped jack (Pseudocaranx dentex).

Lactococcosis, caused by members of the genus Lactococcus, represents a devastating disease inducing mass mortalities and economic losses in many fish species worldwide. The present work aimed to compare the whole genome sequences of three different serotypes of Lactococcus garvieae isolated from diseased cultured striped jack (Pseudocaranx dentex) in Ehime prefecture, Japan. The three serotypes showed different virulence in the challenge test using Japanese amberjack (Seriola quinqueradiata). The genome sequencing revealed that two of the strains (serotype I and serotype III) were identified as L. garvieae, while the third strain (serotype II) was identified as L. formosensis. The chromosome sizes of the three serotypes ranged from 1.9 to 2.0 Mb; the GC content ranges were 38.2 to 38.9%; and the numbers of predicted protein-coding sequences (CDSs) were from 1922 to 1959. Only the serotype II harbours two plasmids, sizes of around 14 kb and 9 kb. The detected virulence factors varied among the different serotypes with some shared factors like adherence, anti-phagocytosis, secretion system, toxin (haemolysin), serum resistance, antimicrobial resistance and others. The genomes also contained factors responsible for resistance to toxic compounds. The genome of the serotype III tended to encode more prophage regions than the other serotypes.

Inhibitory Effects of Modified Atmosphere Packaging Using Pure Oxygen on Discoloration of the Dark Muscle in Cultured Yellowtail (Seriola quinqueradiata) During Refrigerated Storage

ABSTRACT This study showed that the dark muscle of yellowtail stored in pure O2 had almost unchanged redness, pH, and MetMb formation during 72-hour storage, while the N2 and air groups had significantly lower redness and pH, and significantly higher MetMb formation indices. Lactic acid content showed a significant negative correlation with pH. Pearson correlation analysis demonstrated that the lower redness was correlated with the lower pH and higher MetMb formation index. Thus, pure O2 could inhibit the MetMb accumulation and decrease pH, thereby suppressing discoloration and making the dark muscle more likely to gain bright red color.

Establishment of the Life Cycle of <i>Philometroides seriolae</i> (Nematoda: Philometridae) Using Surrogate Copepod Intermediate Host

Philometoides seriolae is a large nematode parasite in the skeletal musculature of Japanese amberjack Seriola quinqueradiata. ​Philometrid nematodes generally use copepods as the intermediate host. ​However, the life cycle of P. seriolae remains unknown, including its intermediate host. ​Instead of finding the true intermediate host from natural environments, we used the copepod Tigriopus japonicus as a surrogate host to experimentally complete life cycle of the nematode. ​Fresh first stage larvae were obtained from the uterus of mature P. seriolae from naturally infected Japanese amberjack. ​Tigriopus japonicus actively fed on hatched larvae, which established infection in the hemocoel at a consistently high rate. ​Twenty-three to 27 days later, the infected T. japonicus were fed to artificially produced juvenile Japanese amberjack. ​About 11 months later, adult female nematodes were recovered from the skeletal musculature of the experimentally infected fish. ​This is the first report of experimental completion of life cycle from hatched larvae to adults in marine philometrid species. ​It would take more than a year for P. seriolae females in the definitive host to be able to produce and disseminate larvae, as those recovered from the experimental fish were still young with eggs in the uterus.

Draft Genome Sequence of Granulicatella sp. Strain S8, Isolated from a Marine Fish, Seriola quinqueradiata

In this study, Granulicatella sp. strain S8 was isolated from the gut of a marine fish, Seriola quinqueradiata, and the draft genome was sequenced. Various genes responsible for pathogenesis, metabolite biosynthesis, defense, and lactic acid production were predicted. The genome sequence of this facultative anaerobe provides insights into its distinctive features.

Identification of a Tissue Inhibitor of Metalloproteinase-2: An Endogenous Inhibitor of Modori-Inducing Insoluble Metalloproteinase from Yellowtail Seriola quinqueradiata Muscle.

The existence of an endogenous protease inhibitor (EPI) was expected from the comparison of the gel properties between washed and nonwashed yellowtail surimi gels. A possible candidate, tissue inhibitor of metalloproteinase-2 (TIMP-2), was partially purified from the soluble fraction of yellowtail muscle, and an 18 kDa protein band was detected by sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) under nonreducing conditions and western blot analysis. Its N-terminal amino acid sequence was determined as XSXSPAHPQQAF, with high homology to TIMP-2 from other fish species, suggesting that it was identified as yellowtail TIMP-2. Subsequently, full-length cDNA of two isoforms (TIMP-2a and TIMP-2b) was successfully cloned from yellowtail muscle. The N-terminal sequence of purified TIMP-2 completely corresponded to TIMP-2b. When the surimi gel quality decreased after spawning, the mRNA expression of TIMP-2b also decreased. Human TIMP-2 could inhibit autolysis of myofibrillar proteins from yellowtail muscle. Thus, TIMP-2b was considered the major EPI of the modori-inducing insoluble metalloproteinase in yellowtail muscle.

Heritability of resistance to benedeniosis in Japanese yellowtail (Seriola quinqueradiata) estimated based on long term repeated measurements in field trials

The aim of this study is to assess the feasibility of the genetic improvement of traits related to resistance to the monogenean ectoparasite Benedenia seriolae in Japanese yellowtail Seriola quinqueradiata. Resistance to benedeniosis (incidence of infection by Benedenia parasites) of individual sample fish was evaluated over two generations in long term field trials, as repeated counts of the number of parasites attached to their skin surface. The broodstock was evaluated by repeated counts 12 times, and 13 resistant and 5 susceptive individuals were selected as the parents among 779 candidates. Fourteen families were produced by mating the selected parents and 598 progenies were evaluated by repeated counts 4 times. A total of 7550 phenotypic records for the 1377 individuals were applied to the repeated measures animal model. Estimates of heritability and repeatability for resistance were as h2 = 0.28 ± 0.03 and R = 0.37 ± 0.01, respectively. The differences of resistance among the families were significant and reflected the performances of the selected parents. Whereas severities of benedeniosis varied among the evaluation periods, the individual and family performances of resistance were consistent throughout the study. Both genetically and phenotypically, there were no significant correlations between resistance and body size traits. This report indicates that selective breeding is a promising approach to control benedeniosis in Japanese yellowtail aquaculture.

Olfaction and gustatory senses promote feeding through different pathways in yellowtail, Seriola quinqueradiata

For sustainable aquaculture, the replacement of dietary fishmeal with plant protein is becoming more common because fishmeal resources are limited. However, in the case of carnivorous fish such as yellowtail (Seriola quinqueradiata), reducing the dietary fishmeal level often causes low feed intake. Improving feed intake is important in the use of a non- and low-fishmeal diet. However, little is known about the mechanisms that regulate feeding in yellowtail. The relationship between appetite, feeding behaviour, and food intake needs to be examined to elucidate the mechanisms of feeding regulation. The senses of smell (olfaction) and taste (gustation) are important for feeding in fish. However, it is unclear how each of these senses stimulates feeding behaviour, appetite, and feed intake. In this study, the effects of olfactory and gustatory stimuli on feeding behaviour, brain expression of neuropeptide Y (NPY), and feed intake in yellowtail were investigated using a strong olfactory stimulant (alanine, Ala) and a strong gustatory stimulant (proline, Pro). By using observation tanks, feeding behaviour was divided into ‘search’ and ‘bite’. Ala promoted ‘search’ feeding behaviour and significantly decreased npy mRNA expression in the olfactory bulb and telencephalon as the olfactory centre and hypothalamus as the appetite centre. No increment in feed intake was found in the Ala-supplemented diets compared to the control diet. Meanwhile, Pro increased npy mRNA expression in the gustatory centre (cerebellum), promoted ‘bite’ feeding behaviour, and increased feed intake. Odour stimulation promoted ‘search’ through npy mRNA expression but was not reflected in feed intake. Taste stimulation promoted ‘bite’ through npy mRNA expression, which increased feed intake. Thus, olfactory and gustatory senses may promote feeding through different pathways in the yellowtail. These results will contribute to increasing the feeding amount of non- and low-fishmeal diet in the feed of yellowtail towards sustainable aquaculture.

New records of three commercial fish hosts for two Unicapsula spp. and Kudoa megacapsula (Myxozoa: Myxosporea: Multivalvulida)

Infections caused by multivalvulid myxosporeans belonging to genera Unicapsula and Kudoa (Cnidaria: Myxozoa) occasionally affect commercial marine fish species. Postmortem myoliquefaction caused by a variety of Kudoa spp., including K. thyrsites, and unsightly cyst or pseudocyst formation, caused by K. amamiensis, U. muscularis, and other kudoid species, negatively affect commercial values of fillets. However, multivalvulid infections are often latent and imperceptible in the market. Biodiversity, host range, and epidemiology remain to be explored. Here, myxosporean infection was detected in four commercial fish species from southern China, using morphological and molecular analyses. Three Unicapsula spp. (U. pyramidata in Nemipterus japonicus; U. pflugfelderi in Dentex angolensis transported from the Eastern Central Atlantic Ocean, off West African coast; and U. aequilobata in Decapterus macarellus) and Kudoa megacapsula in Nemipterus virgatus were observed to form pseudocysts in the myofibers of the host trunk muscles. All fish hosts identified here, except for U. pyramidata, are new records. Kudoa megacapsula was morphologically characterized by gigantic, cruciform myxospores with four wing-like shell valves morphologically comparable to previous Japanese records of the same species in aquaculture facilities, acquiring fly from China or Korea (Sphyraena pinguis and Seriola quinqueradiata, respectively). Molecular analyses established the conspecificity of the present Chinese isolate with previously recorded Japanese isolates. To our knowledge, for the first time, a partial large subunit ribosomal RNA gene sequence of K. megacapsula was obtained, showing close phylogenetic relationships with Kudoa spp. harboring cruciform myxospores, such as K. thyrsites, K. gunterae, K. whippsi, and K. lateolabracis.

Identification of a rabbit Ig light chain recombinant protein bound to serum immunoglobulins from different marine fish species

The structures of fish serum immunoglobulin differ among different fish species. In this study, we accidently isolated a rabbit immunoglobulin (Ig) light chain bound to serum immunoglobulin from different marine fish species using phage display. Fish Ig was separated using a protein A column. The phage library was generated from variable regions of rabbit spleen B cells immunized with bluefin tuna Thunnus orientalis Ig. Fish Ig–specific phages were enriched using two rounds of bio-panning with yellowtail Seriola quinqueradiata serum Ig, followed by two rounds of bio-panning with red seabream Pagrus major serum Ig. The enriched phages demonstrated an increase in binding specificity to the tuna, yellowtail, and red seabream Igs compared to the phages listed in the unpanned library. A recombinant protein of a single clonal phage, which encodes the rabbit Ig light chain, was produced, and the binding specificities to fish Igs were analyzed using enzyme-linked immunosorbent assay (ELISA) and western blotting. The recombinant protein exhibited binding properties to fish Igs in the ELISA. However, the recombinant protein that bound to serum protein(s), but not IgM, was detected via western blotting. The recombinant protein may provide a novel information on the common structural feature in the fish immunoglobulins.

Genetic parameter estimation for resistance to red tide raphidophyte Chattonella antiqua in Japanese yellowtail Seriola quinqueradiata

Blooms of the harmful algal plankton Chattonella spp. cause severe economic damage to aquaculture. This study aimed to investigate the potential for selective breeding of resistance trait to Chattonella red tides in Japanese yellowtail Seriola quinqueradiata. Two experimental populations were prepared using different production procedures, one was produced by full factorial mating and common rearing tanks, and another was produced by pair mating and family separated rearing tanks. Fingerlings were exposed to mass cultured Chattonella antiqua and their mortality time was recorded as the phenotype of Chattonella resistance. There were significant differences in survival rate among full-sib families (range 0–50%). Heritability estimates of mortality time were moderate and similar in both populations as 0.329 ± 0.104 and 0.314 ± 0.118 respectively. The environmental variance caused by difference in rearing tanks was relatively small compared with the genetic variance, and had minimal influence on genetic parameter estimation. In contrast, body weight was highly influenced by the environmental variance of rearing tanks, thus heritability estimates varied between populations, 0.275 ± 0.102 and 0.153 ± 0.083 respectively. The genetic correlation between mortality time and body weight was not significant. This is the first report that reveals the contribution of a genetic difference to Chattonella resistance and indicates the potential for selective breeding of Chattonella resistance in Japanese yellowtail.

Modelling torus behaviour in a fish farming cage

AbstractSince it is not usually possible to observe all of the fish in a school, it is difficult to monitor farmed fish in a crowded cage with the aim of scrutinising their condition. One possible solution to this problem is the use of simulations. The aim of this study is to simulate fish movement in a cage to be able to propose an optimal monitoring method based on limited observations made by instruments. In this study, we observed a Yellowtail (Seriola quinqueradiata) school in a fish cage at a fish farm and attempted to simulate their movement. The Yellowtail, while milling in a cage, forms a stable truncated cone‐shaped school. We successfully reproduced this shape of school by including the effects of negative phototropism and the hypothetical forces that fish experience from the cage wall, in addition to the forces of attraction, repulsion and orientation that have been postulated in previous studies. We also included the effect of intraspecific interaction. We hypothesise that longer fish exert a greater repulsive force on smaller fish. The results of our simulation suggest that the position of any fish in a school is thus a function of its length.