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Ultrastructural analysis of epitheliocystis organisms from gills of anadromous juvenile steelhead trout, Salmo gairdneri Richardson, revealed the presence of several distinct forms. Two oval infectious organisms resembled previously described agents and had chlamydia-like characteristics. One form had a distinct oval head region from which a tail-like structure projected. These prokaryotic forms have an ultrastructural appearance which has not been described in previous reports of epitheliocystis. Morphological analyses of gill epithelial cells of S. gairdneri suggest that each cyst remains contained within the cytoplasm of a single host cell. [ABSTRACT FROM AUTHOR]

The aim of the present study was to assess if pre-exposure to water copper and/or polyvinyl chloride microparticles affects the transcriptional responses of common carp, Cyprinus carpio, to saltwater exposure. Fish were exposed to 0.25 mg/L copper alone (Cu) or in the presence of 0.5 mg/L polyvinyl chloride microparticles (Cu-MPVC) for 14 days, followed by 72 hours of salt water exposure (0 to 13 ppt NaCl). The copper content in the gills and the expression of heat shock protein (hsp70) and cytochrome P450 family 1 (cyp1a) transcripts were examined. The results showed that gill copper levels increased significantly (P = 0.008) in the Cu and Cu-MPVC treatments after 14 days of exposure, compared to the control fish; the Cu and Cu-MPVC treatments had similar gill copper levels. After 14 days of exposure, branchial expression of the hsp70 and cyp1a genes was significantly up-regulated in the Cu and Cu-MPVC treatments. Exposure to salt water led to a significant down-regulation of the gene transcripts in all treatments after 24 h of exposure. At this point, the Cu and Cu-MPVC treatments showed transcripts similar to those of the control fish prior to saltwater exposure. The fish treated with Cu-MPVC showed significantly higher hsp70 expression 72 h after saltwater exposure than the other treatments. At this time point, the control and Cu fish had significantly lower cyp1a expression than before saltwater exposure. In conclusion, the present data suggest that copper exposure induces stress in the fish gills, and the presence of MPCV in the water hampers normal transcriptomic responses of the fish gills to saltwater exposure. [ABSTRACT FROM AUTHOR]

Introduction: Nowadays, using unconventional water, especially in arid and semi-arid areas, has increased as a result of global population increase, urbanization and climate change. Using these water sources for aquaculture is suggested for optimal utilization and reduction of their adverse effects on the environment. Artemia is an aquatic crustacean that is distributed all over the world. It plays an important role in the aquatic food chain due to containing a variety of high nutrients such as proteins, amino acids, fatty acids, vitamins and antioxidants. These organisms are the most common live-food item in the aquaculture industry to feed the larval stages of fish and crustaceans in different parts of the world. Artemia can grow in various saltwater environments. The water sources suitable for them do vary considerably in terms of ionic composition, climatic conditions, seasonality, productivity, altitude, and other characteristics. Among the species of the genus Artemia, A. franciscana is the most important one for aquaculture use, and it has been introduced in salt-waters for integrated Artemia-salt production. This species is characterized by the standard features of the short-life cycles: highly adaptable to adverse environmental conditions, easy cultivation and easy availability. The aim of this study was to investigate the feasibility of hatching and growth performances of Artemia (A. franciscana) in the unconventional water conditions in Sistan region, Southeast Iran under laboratory conditions. Materials and methods: The present study was carried out in the Laboratory of Reproduction and Breeding Aquatic Animals, Hamoun International Wetland Research Institute located in Zabol Research Institute in February 2024. Hatching rate, growth performance (comparison of body length and width), abundance of each biological form and health (comparison of morphological characteristics) of A. franciscana under breeding conditions of unconventional waters in Sistan region were investigated in this study. For this purpose, Artemia cysts were hatched in plastic jars using three replicated treatments, i.e., control (T1; distilled water + sea salt; 35.37 ppt), desalination wastewater (T2; 48.88 ppt), deep aquifer well water (T3; 16.35 ppt), and well water (T4; 28.46 ppt). All treatments were kept under standard conditions including temperature 27 °C, light 37 μmol/m2 /s as well as 12 hours light and 12 hours darkness (12L:12D) during the experimental period. After 48 h of incubation, the hatching rate of Artemia cysts was analyzed. In order to evaluate growth performance and health status, at least 30 specimens from each treatment were randomly selected and photographed, then body length and width were measured using Digimizer software. Water quality parameters including temperature, pH, salinity, ammonia, nitrate, nitrite, sulfate, hardness, Cl, Mg and Cu were recorded using standard methods during the experiment. All data obtained in this study were analyzed using One-Way ANOVA, followed by Tukey's test for any significant differences among the treatments. Pearson’s correlation coefficient (r) was calculated for the statistical interpretation of the influence of the physicochemical variables on hatching rate and body length. Results and discussion: The results showed that hatchability of cysts and body length of Artemia were significantly different among treatments (p<0.05). The highest value of 71.32 ± 5.41% was recorded in T1 followed by 67.19 ± 4.28% in T3, 51.19 ± 2.33% in T4 and 47.81 ± 2.78% in T2 on the 48 h after cyst incubation. The length (mm) of Artemia was higher (0.64 ± 0.06) in T3 than in T1 (0.62 ± 0.05), T4 (0.59 ± 0.04) and T2 (0.56 ± 0.05). Instar 2 was the dominant form in T3 and T4, while instar 2 was the dominant form in the other two treatments. The morphological characteristics of Artemia were similar and normal between all treatments. The results showed that although the hatchability of cysts was more affected by the breeding environment, the growth of Artemia in all the unconventional water treatments was suitable compared to the control treatment, and also the morphological characteristics of Artemia were normal in all treatments. Due to the occurrence of long-term droughts in Sistan region, the only opportunity for the continuation of aquaculture, especially in recent years, lies in the use of unconventional saline water resources in this region. So, the present study provides the first evidence of relatively favorable hatching and suitable initial growth of Artemia in unconventional saline waters, especially desalination wastewater, in Sistan region and shows that cultivation Artemia is biologically possible in the unconventional waters under laboratory conditions. Conclusion: The data presented in this study generate the first useful information for the future inoculation of Artemia in unconventional waters (desalination wastewater, deep aquifer well water and well water) in Sistan, and hence domestic Artemia production in the country. However, further larger-scale laboratory work, followed by field trials, is still needed. [ABSTRACT FROM AUTHOR]

Sample digestion and complete dissolution are prerequisites for the precise and accurate elemental analysis of ores and minerals by instrumental analytical methods. Pegmatite ores containing refractory mineral phases are not effectively attacked and dissolved by the low boiling HF–HCl/HNO3 mixture. A novel, rapid, and efficient NH4HF2-assisted KH2PO4 fusion has been standardized for multi-elemental determination of geological samples containing refractory mineral phases. Critical parameters, such as the sample-to-flux ratio, digestion temperature, and contact time of the ore with ammonium bi-fluoride (ABF), were optimized and reported. The novel fusion method has been demonstrated to be effective for the quantitative recovery of all the analytes, including Ti, W, and, especially, Sn. The repeatability of the method was estimated analyzing a control sample. The relative standard deviaiton among replicates for all the analytes were below 3%. The accuracy was established using certified reference materials (IGS-26, IGS-33, and BH-1). All the target analytes were recovered at more than 95% in CRMs. Other validation parameters, such as robustness, selectivity, and LOD/LOQ are also described. This method can be routinely and safely used for the determination of Li, Rb, Nb, Ta, Ti, Mn, Sn, and W in addition to Fe, Ca, Mg, and Al in pegmatite ores. [ABSTRACT FROM AUTHOR]

Improving nitrogen use efficiency (NUE) has become increasingly important to growers due to the steep rise in fertiliser prices since 2021. This has focussed attention on improving practices that no longer make economic sense, such as applying 'just a little extra' nitrogen (N) as an insurance. One of these practices is the application of late N fertiliser to milling wheat to enhance protein for breadmaking quality. This paper describes the development of a new protein prediction test that helps farmers decide whether it is necessary to apply this extra N fertiliser or not. The new test, based on the measurement of nitrate-N (NO3-N) in the roots, was found to be an improvement in its accuracy of predicting grain protein content compared to current indicators, such as the determination of leaf N or using a SPAD/chlorophyll meter, due to its increased sensitivity at N supplies above 200 kg N/ha. It was found that 50% of farmers did not achieve the milling specification of above 13% protein content, despite applying late N fertiliser, and that the protein prediction test was able to identify those fields where the N supply was sufficient, hence improving both NUE and reducing fertiliser wastage. Timing of sampling was important for the effectiveness of the test, with the later the samples were taken, the better the prediction. It is not recommended to sample during a period of drought, as lack of moisture prevented N uptake into the crop. Since the NO3-N concentration in roots accurately reflected the N status of the crop at the time of sampling, it was speculated that this could help identify other factors, such as climate conditions or management practices, which influence N uptake efficiency. For example, it was found that N uptake is reduced at soil temperatures below 10°C, which could be translated into practical advice to farmers to prevent N leaching. Some preliminary results of this research are presented in this paper. Of the farmers using the protein prediction test, 82% received the correct advice on whether they should apply extra N fertiliser or not and the relationship between predicted and harvest protein closely followed the 1:1 line. Overall, the protein prediction test was found to be an effective tool to help growers decide whether late N is required. [ABSTRACT FROM AUTHOR]

Methionine is an indispensable amino acid with an important role as the main methyl donor in cellular metabolism for both fish and mammals. Metabolization of methionine to the methyl donor S-adenosylmethionine (SAM) has consequence for polyamine, carnitine, phospholipid, and creatine synthesis as well as epigenetic modifications such as DNA- and histone tail methylation. Methionine can also be converted to cysteine and contributes as a precursor for taurine and glutathione synthesis. Moreover, methionine is the start codon for every protein being synthetized and thereby serves an important role in initiating translation. Modern salmon feed is dominated by plant ingredients containing less taurine, carnitine, and creatine than animal-based ingredients. This shift results in competition for SAM due to an increasing need to endogenously synthesize associated metabolites. The availability of methionine has profound implications for various metabolic pathways including allosteric regulation. This necessitates a higher nutritional need to meet the requirement as a methyl donor, surpassing the quantities for protein synthesis and growth. This comprehensive review provides an overview of the key metabolic pathways in which methionine plays a central role as methyl donor and unfolds the implications for methylation capacity, metabolism, and overall health particularly emphasizing the development of fatty liver, oxidation, and inflammation when methionine abundance is insufficient focusing on nutrition for Atlantic salmon (Salmo salar). [ABSTRACT FROM AUTHOR]

Nephrocalcinosis is a widespread challenge in intensive production of salmon smolt. There is however no consensus on its aetiology, which makes it problematic to implement proper measures to limit its development. We performed a survey of nephrocalcinosis prevalence and environmental factors in 11 different hatcheries in Mid‐Norway as well as a 6‐month monitoring in one of the hatcheries. A multivariate analysis indicated that the most influencing factor for the prevalence of nephrocalcinosis was the supplementation of sea water during smolt production. In the 6‐month monitoring, the hatchery introduced salinity in the production water prior to the change in day length. Mismatch in those environmental signals may increase the risk for developing nephrocalcinosis. Salinity fluctuations prior to smoltification can cause osmotic stress and result in unbalanced levels of ions in fish blood. This was clearly illustrated in our study, as the fish experienced chronic hypercalcaemia and hypermagnesaemia. Both magnesium and calcium are excreted over the kidneys and it is possible that their prolonged, elevated levels in plasma resulted in an oversaturation of the urine when finally excreted. This again could have led to the aggregation of calcium deposits within the kidney. This study indicates a relationship between osmotic stress induced by salinity changes in juvenile Atlantic salmon and the development of nephrocalcinosis. Other factors that may affect the severity of nephrocalcinosis are currently subjects for discussion. [ABSTRACT FROM AUTHOR]

Long-term in situ measurements of the temperature of hydrothermal fluids have great significance in the research of seafloor hydrothermal activities. Herein, we developed a self-powered battery-free temperature logger for measuring and recording the temperature of hydrothermal fluids. A gravity heat pipe made of titanium alloy was employed as the heat-conducting element of the temperature logger to capture heat from a hydrothermal vent and transfer it to the thermoelectric unit. The thermoelectric generator used herein converted the temperature difference into electrical energy to power the circuit of the temperature logger. Numerical analyses and experiments were performed to investigate the performance of the heat pipe and temperature logger. Results show that the temperature logger can realize self-powered starting at a temperature of >76 °C during a tank test. This paper presents a discussion on a new instrument for temperature measurements of deep-sea hydrothermal fluids. [ABSTRACT FROM AUTHOR]

Herpesvirus infections of sturgeon pose a potential threat to sturgeon culture efforts worldwide. A new epitheliotropic herpesvirus named Acipenser herpesvirus 3 (AciHV-3) was detected in hatchery-reared Lake Sturgeon Acipenser fulvescens displaying skin lesions in central Canada. The growths were discovered in the fall, reached average prevalence levels of 0.2–40% and eventually regressed. No unusual mortality was observed. The cellular changes within the lesions included epithelial hyperplasia and were reminiscent of other herpesvirus infections. The virus was not evident in lesions examined by electron microscopy. Skin tissue homogenates from symptomatic sturgeon produced atypical cytopathic effects on a primary Lake Sturgeon cell line, and next-generation sequence analysis of the DNA samples revealed the presence of an alloherpesvirus. A new genotyping PCR assay targeting the major capsid protein sequence detected AciHV-3 in symptomatic Lake Sturgeon as well as other apparently healthy sturgeon species. Bayesian inference of phylogeny reconstructed with a concatenation of five alloherpesvirus core proteins revealed a new Alloherpesviridae lineage isomorphic with a new genus. The presence of AciHV-3 homologs in cell lines and sturgeon sequence datasets, low sequence divergence among these homologs and branching patterns within the genotyping phylogeny provide preliminary evidence of an endogenous virus lifestyle established in an ancestral sturgeon. [ABSTRACT FROM AUTHOR]

The onset of transition to cellularity and self-similar propagation of centrally ignited, expanding spherical flames in a reactive environment of H2/O2/N2 and H2/O2/He mixtures at initial pressures up to 15 bar were experimentally investigated using a newly developed, constant-pressure, dual-chamber vessel and were theoretically interpreted based on linear stability theory. The experiments were well-controlled to identify the separate and coupled effects of Darrieus–Landau instability and diffusional–thermal instability. Results show that the critical radius, rcr, for the onset of cellular instability varies non-monotonously with initial pressure for fuel-lean and stoichiometric H2/O2/N2 flames. This non-monotonous pressure dependence of rcr is well captured by linear stability theory for stoichiometric flames. The experimental critical Peclet number, Pecr = rcr/δf, increases non-linearly with the Markstein number, Ma, which measures the intensity of diffusional–thermal instability. However, a linear dependence of Pecr on Ma is predicted by linear stability theory. Specifically, the theory shows well quantitative agreement with the experimental results for mixtures with near-unity Leeff; however, it under-predicts the Pecr for mixtures with off-unity Leeff. In addition, there exists three distinct propagation stages for flames subjected to cellular instability, namely, smooth expansion, transition propagation, and self-similar propagation. The acceleration exponent, α, in the self-similar propagation stage was extracted based on the power-law of drf/dt = αA1/αrf(1 − 1/α), where rf is the instantaneous mean flame radius, and A is a constant. The values of α are located between 1.22 and 1.40, which are smaller than the suggested value (1.5) for self-turbulization. [ABSTRACT FROM AUTHOR]

Environmental damage must be taken seriously. Strengthening human attitudes to preserve the environment is the keyword, and strengthening the aspects of knowledge about the environment must be pursued. However, a scientific basis is needed that shows that it is true that strengthening the aspects of knowledge about the environment can improve a person's attitude toward preserving the environment. The purpose of this research is to find the relationship between a person's knowledge and their behavior in preserving the environment. By defining the general picture of the relationship between knowledge and attitudes, future accurate educational policies can be taken in the context of environmental protection. This research is a meta-analysis of correlation types. The inclusion criteria for selecting the data are as follows: studies published from 1999 to 2022 in English, analyzed by correlation analysis, have descriptions of many samples and correlation indices, and published in Google Scholar-indexed journals. Based on this inclusion criteria, 23 studies were selected containing 36 relevant sets of research data. The results showed that there was a correlation between knowledge and a person's attitude toward the environment (.37). Assuming a 95% confidence level, the real score ranges from 0.26 to 0.48. The publication bias test using the trim and fill method showed that none of the data contained biased publications, so the meta-analysis results could be declared valid. Now, there is an urgency to expand environmental education to encourage the development of good attitudes by the community toward the environment. [ABSTRACT FROM AUTHOR]

A feeding experiment was conducted to study the effects of dietary lipid sources and L-carnitine on the growth performance, body component, muscle fatty acid composition, and antioxidant enzyme ability of average weight of 0.28 g dog conch larvae, Laevistrombus canarium. Three sources of lipid: fish oil, soybean oil, and beef tallow were tested in combination with two levels (0 and 0.5%) of L-carnitine. The dog conch larvae fed diets containing fish oil with L-carnitine supplementation exhibited the highest weight gain. After air exposure challenge, the liver tissue of dog conch fed the diets containing soybean oil and beef tallow without supplemented L-carnitine had lower levels of superoxide dismutase (SOD, U min−1), phenoloxidase (PO, U min−1), and glutathione peroxidase (GPx, mU/mL) activity. The activity of SOD, PO, and GPx of dog conch larvae increased with increasing levels of dietary L-carnitine. In particular, dog conch larvae fed the diet containing fish oil supplemented with L-carnitine exhibited significantly (P < 0.05) enhanced antioxidant responses. The thiobarbituric acid reactive substances (TBARS) in the muscle tissue of dog conch larvae fed the diet containing fish oil without L-carnitine supplementation showed significantly (P < 0.05) higher activity. It was concluded that dietary administration of L-carnitine can enhance resistance against beta-oxidation, and the administration of fish oil in the diet was the best strategy to promote growth due to high nutritional availability. [ABSTRACT FROM AUTHOR]

This study presents novel data on the microanatomy and ultrastructure of the omul Coregonus migratorius trunk kidney. Adult individuals of C. migratorius were sampled in the Barguzin Bay of Lake Baikal. Active leuko‐ and erythropoiesis were found in the interstitium of the mesonephros. For the first time, cells with radially arranged vesicles have been described in the renal interstitium of C. migratorius. The quantitative characteristics of blood cells and ultrastructural parameters of leukocytes reflected the functioning of the non‐specific defence system in the organism. The share of the renal interstitium, morphological diversity of the epithelial cells of the nephron tubules, the ultrastructural features of the renal corpuscles and nephron tubules and the number of mitochondria in leukocytes and ion‐transporting cells were typical for representatives of the whitefish Coregonus lavaretus complex and thus considered ancestral features of the present‐day C. migratorius population reflecting its adaptive potential to living in an ultra‐deep Lake Baikal. [ABSTRACT FROM AUTHOR]

Protein ingredients for formulation of fish feeds are expensive and have limited availability. Therefore, reducing dietary protein while increasing dietary fat content is a common practice in rearing carnivorous fish species. However, the ability of dietary L-carnitine to alleviate adverse effects in such diets is currently unknown. This study investigated the role of L-carnitine supplementation in alleviating adverse effects on growth performance, energy metabolism, antioxidant capacity, and inflammation response in juvenile largemouth bass (Micropterus salmoides) fed on a low protein and high fat diet. Three diets were formulated to contain low protein and high fat (LPHF: 420 g kg-1 protein and 150 g kg-1 lipid), LPHF supplemented with L-carnitine (LPHFC: 420 g kg-1 protein and 150 g kg-1 lipid), and a control diet (CON: 480 g kg-1 protein and 130 g kg-1 lipid). The diets were fed to 30 largemouth bass (10.75 ± 0.01 g) juveniles in triplicates for eight weeks. The results showed that the fish feed on LPHF diet increased hepatosomatic index, visceral somatic index, mesenteric fat index, whole-body crude fat content, serum and liver triglyceride concentrations, and serum non-esterified fatty acid level than those fed on CON diet. Moreover, the fish fed on LPHF diet increased serum alanine aminotransferase activity and liver malondialdehyde content and reduced superoxide dismutase (SOD) activities in the serum and liver. Furthermore, the fish fed on LPHF diet reduced the whole-body crude protein content. Interestingly, feeding the fish on the LPHFC diet decreased fat deposition and liver damage by downregulating the expression of genes related to lipogenesis, inflammation, and increased SOD activity. This study indicates that L-carnitine supplementation in largemouth bass alleviates the adverse effects caused by LPHF diet by decreasing lipogenesis and increasing lipid catabolism. Our study provides novel knowledge on strategies to improve utilization of LPHF diet in cultured aquatic animals. [ABSTRACT FROM AUTHOR]

All-female giant freshwater prawn Macrobrachium rosenbergii has a significant growth limitation due to its early sexual maturity. A 60-day trial was carried out to determine the effect of beta-agonist, ractopamine hydrochloride (RAC), on the growth performance, body composition, and gonadal maturation of all-female prawns. Prawn juveniles (4.39 ± 0.40 g initial weight) were stocked at 10 prawns/m2 in 15 plastic tanks (1000 liters each) in a completely randomized design with four treatments and a control (0, 5, 10, 15, and 20 mg/kg) in triplicate. The significantly (p < 0.05) highest values of final weight, weight gain, daily weight gain, and specific growth rate (SGR) were observed in the female prawns fed with the diet containing 10 mg/kg RAC, while the lowest values were found in the control tank. Similarly, survival rate, feed conversion rate (FCR), and condition factors were observed among all treatments, which were significantly better than the control (0 mg/kg). Significantly greater yield and lower gonadosomatic index (GSI) values were obtained in prawns fed with a 10 mg/kg RAC-containing diet than in all other treatments, except for the diet containing 15 mg/kg RAC, while the lowest yield was produced by the control tank. A diet containing 10 mg/kg RAC had significantly improved the whole-body protein content in prawns, while diets containing 10 and 15 mg/kg RAC exhibited lower lipid content in prawns than in the other treatments. A significant increase in the number of Stage 1 (virgin) females (up to 54% at 10 mg/kg RAC diet) was found in all RAC treatments, while the control had a significantly higher number of females at various maturity stages, indicating that RAC administration effectively suppresses gonadal maturity. Residue analysis of whole prawn samples at the end of the trial indicated no trace of ractopamine. The quadratic regression analysis of weight gain, SGR, FCR, and yield revealed that the optimum dietary ractopamine level for all-female prawn culture should be between 10 and 15 mg/kg. [ABSTRACT FROM AUTHOR]

A reducing system of SoxR, a regulator of redox-active molecules, was identified as rsxABCDGE gene products and RseC in Escherichia coli through genetic studies. We found that ApbE was an additional component of the reducer system. Bacterial two hybrid analysis revealed that these proteins indeed had multiple interactions among themselves. RseC and RsxB formed the core of the complex, interacting with more than five other components. RsxC, the only cytoplasmic component of the system, interacted with SoxR. It might be linked with the rest of the complex via RsxB. Membrane fractions containing the wild type complex but not the mutant complex reduced purified SoxR using NADH as an electron source. These results suggest that Rsx genes, RseC, and ApbE can form a complex using NAD(P)H to reduce SoxR. [ABSTRACT FROM AUTHOR]

Intensive aquaculture production systems often encounter infectious viral disease outbreaks causing substantial fish mortalities and associated economic losses. Blue catfish alloherpesvirus (BCAHV) is an Ictalurid herpesvirus with limited information on pathogenesis. To determine the host‐specificity and potential host range of BCAHV, the virus was inoculated onto various fish cell lines belonging to families Ictaluridae, Cyprinidae, Centrarchidae, and Clariidae. Viral replication and exhibition of cytopathic effects (CPEs) were restricted to cell lines from the family Ictaluridae indicating the host preference of BCAHV. Subsequently, fish challenges were conducted to evaluate intrinsic and extrinsic factors influencing BCAHV infection. Mortality because of BCAHV infection was significantly higher in blue catfish and least in channel catfish further specifying the host preference of the virus. Histopathological assessment of the BCAHV infected fish revealed splenitis with severe erythrophagia. Host susceptibility to BCAHV differed with age with fish at 60 days post hatch being more susceptible. Temperature had a significant role in the activation and pathogenesis of BCAHV. Fish exposed to BCAHV at a sustained high temperature had significantly low mortality suggesting the likelihood of virus inactivation. Virus exposure in tanks with high stocking density resulted in significantly high fish mortalities indicating horizontal transmission is a key element in BCAHV pathogenesis. The heightened pathogenicity of BCAHV in blue and hybrid catfish as observed in this study validates its potential to be a significant pathogen in catfish production. [ABSTRACT FROM AUTHOR]

The study determined the combined effect of dietary l‐carnitine (non‐essential organic nutrient) and ractopamine (feed additive) on growth performance and nutritional composition of Labeo calbasu. To ascertain this, a 60‐day feeding trial was carried out under a controlled condition where two hundred and twenty‐five healthy L. calbasu fingerlings (avg. wt. 3.47 ± 0.1 g) were divided into four treatments group and one control group in triplicate. Therefore, the respective combination of l‐carnitine and ractopamine diet was fed to L. calbasu fingerlings as C: control or basal feed without l‐carnitine and ractopamine; T1:1 g kg−1l‐carnitine and 10 mg kg−1 ractopamine; T2: 2 g kg−1l‐carnitine and 20 mg kg−1 ractopamine; T3: 3 g kg−1l‐carnitine and 30 mg kg−1 ractopamine and T4: 4 g kg−1l‐carnitine and 40 mg kg−1 ractopamine, respectively. Upon completion of the 60‐day feeding experiment, eight fish were randomly collected from each tank and subjected to a series of laboratory analyses. The study determines that T2 group fish significantly (p <.05) improved the WGP (244.66 ± 20.59%), SGR (0.89 ± 0.04), PER (2.20 ± 0.14) and increased crude protein content in fish muscle. In addition, many essential amino acids were recorded significantly high (p <.05) in the fish fed with diet T2 compared with others. Hence, dietary supplementation of l‐carnitine and ractopamine at 2 g kg−1 and 20 mg kg−1 in combination is beneficial for growth and nutritional composition of L. calbasu. [ABSTRACT FROM AUTHOR]

Herein we investigated the cellular responses of the endemic fish species Alburnus vistonicus Freyhof & Kottelat, 2007, under the variation of several physico-chemical parameters including temperature (°C), salinity (psu), dissolved oxygen (mg/L), pH and conductivity (μS/cm), which were measured in situ. Monthly fish samplings (October 2014–September 2015) were conducted in Vistonis Lake in northern Greece, a peculiar ecosystem with brackish waters in its southern part and high salinity fluctuations in its northern part. Fish gills and liver responses to the changes of the physico-chemical parameters were tested biochemically and histologically. Heat shock protein levels appeared to be correlated with salinity fluctuations, indicating the adaptation of A. vistonicus to the particular environment. The latter is also enhanced by increased Na+-K+ ATPase levels, in response to salinity increase during summer. The highest mitogen activated protein kinases phosphorylation levels were observed along with the maximum mean salinity values. A variety of histological lesions were also detected in the majority of the gill samples, without however securing salinity as the sole stress factor. A. vistonicus cellular stress responses are versatile and shifting according to the examined tissue, biomarker and season, in order for this species to adapt to its shifting habitat. [ABSTRACT FROM AUTHOR]

Sulfate (SO42‐) regulation is challenging for euryhaline species as they deal with large fluctuations of SO42‐ during migratory transitions between freshwater (FW) and seawater (SW), while maintaining a stable plasma SO42‐ concentration. Here, we investigated the regulation and potential role of sulfate transporters in Atlantic salmon during the preparative switch from SO42‐ uptake to secretion. A preparatory increase in kidney and gill sodium/potassium ATPase (Nka) enzyme activity during smolt development indicate preparative osmoregulatory changes. In contrast to gill Nka activity a transient decrease in kidney Nka after direct SW exposure was observed and may be a result of reduced glomerular filtration rates and tubular flow through the kidney. In silico analyses revealed that Atlantic salmon genome comprises a single slc13a1 gene and additional salmonid‐specific duplications of slc26a1 and slc26a6a, leading to new paralogs, namely the slc26a1a and ‐b, and slc26a6a1 and ‐a2. A kidney‐specific increase in slc26a6a1 and slc26a1a during smoltification and SW transfer, suggests an important role of these sulfate transporters in the regulatory shift from absorption to secretion in the kidney. Plasma SO42‐ in FW smolts was 0.70 mM, followed by a transient increase to 1.14 ± 0.33 mM 2 days post‐SW transfer, further decreasing to 0.69 ± 0.041 mM after 1 month in SW. Our findings support the vital role of the kidney in SO42‐ excretion through the upregulated slc26a6a1, the most likely secretory transport candidate in fish, which together with the slc26a1a transporter likely removes excess SO42‐, and ultimately enable the regulation of normal plasma SO42‐ levels in SW. [ABSTRACT FROM AUTHOR]

Statistical models built using different data sources and methods can exhibit conflicting patterns. We used the northern stock of black sea bass (Centropristis striata) as a case study to assess the impacts of using different fisheries data sources and laboratory‐derived physiological metrics in the development of thermal habitat models for marine fishes. We constructed thermal habitat models using generalized additive models (GAMs) based on various fisheries datasets as input, including the NOAA Northeast Fisheries Science Center (NEFSC) bottom trawl surveys, various inshore fisheries‐independent trawl surveys (state waters), NEFSC fisheries‐dependent observer data, and laboratory‐based physiological metrics. We compared each model's GAM response curve and coupled them to historical ocean conditions in the U.S. Northeast Shelf using bias‐corrected ocean temperature output from a regional ocean model. Thermal habitat models based on shelf‐wide data (NEFSC fisheries‐dependent observer data and fisheries‐independent spring and fall surveys) explained the most variation in black sea bass presence/absence data at ~15% deviance explained. Models based on a narrower range of sampled thermal habitat from inshore survey data in the Northeast Area Monitoring and Assessment Program (NEAMAP) and the geographically isolated Long Island Sound data performed poorly. All models had similar lower thermal limits around 8.5℃, but thermal optima, when present, ranged from 16.7 to 24.8℃. The GAMs could reliably predict habitat from years excluded from model training, but due to strong seasonal temperature fluctuations in the region, could not be used to predict habitat in seasons excluded from training. We conclude that survey data source can greatly impact development and interpretation of thermal habitat models for marine fishes. We suggest that model development be based on data sources that sample the widest range of ocean temperature and physical habitat throughout multiple seasons when possible, and encourage thorough consideration of how data gaps may influence model uncertainty. [ABSTRACT FROM AUTHOR]

The construction of "photonic molecules" with controlled sizes and shapes is of particular interest for the integration of miniaturized devices into optoelectronic chips. Here, a general approach is reported that allows the assembly of colloidal microspheres into coupled microcavities with high yield and large scale, utilizing magnetostatic interactions between diamagnetic building blocks dispersed in a ferrofluid under an external field. By precisely designing the local field gradient around diamagnetic microspheres, "virtual templates" can be formed to produce various coupled photonic structures, including diatomic heterogeneous molecules and polyatomic chain molecules. The diatomic structures can modulate the optical resonance modes upon the coherent coupling between microsphere cavities and serve as single‐mode wavelength‐tunable microlasers. The chain photonic molecules, as coupled resonator optical waveguides, could modulate the light propagation and store photons up to tens of picoseconds. The magnetically controlled assembly method is demonstrated, which provides a promising way for the facile and efficient fabrication of coupled microstructures for fascinating photonic and optoelectronic applications. [ABSTRACT FROM AUTHOR]

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This study evaluated the anaesthetic and sedative effects of eugenol applied on yellow catfish (Pelteobagrus fulvidraco). In the anaesthesia induction and recovery experiment, fish were treated with five concentrations of eugenol (0, 15, 20, 25 and 30 mg/L), respectively, and in the transportation experiment, fish treated with 10 mg/L eugenol were evaluated after 12 h simulated transportation. Induction and recovery time were recorded. The induction time shortened with the increasing eugenol concentration, whereas the recovery time prolonged with the increasing eugenol concentration. The effective concentration of eugenol for short‐term anaesthesia induction was between 25 and 30 mg/L. The post‐transportation survival rate of yellow catfish was 100%. The content of ammonia nitrogen in the eugenol group was lower (p < 0.05). Compared with the control group, yellow catfish in the anaesthetized transportation group showed a significant decrease in blood cortisol levels (p < 0.05), whereas the levels of glucose and lysozyme significantly increased (p < 0.05). Both hsp70 and hsp90 mRNA expression in the liver of anaesthetized yellow catfish were found to significantly upregulate after transportation (p < 0.05). In summary, eugenol was an effective anaesthetic for yellow catfish. For short‐term anaesthesia, the recommended concentration is 25–30 mg/L and for long‐time transportation, the appropriate concentration is 10 mg/L in order to reduce stress response of fish. [ABSTRACT FROM AUTHOR]

Ocean warming is leading to poleward range shifts for many fish species, and while well described, potential life history phenology differences within fish populations along a gradient from their historic to current distributional range have not been studied. In a rapidly shifting fish population, the Northern stock of black sea bass (Centropristis striata), we investigated spawning phenology and output across the US Northeast Shelf to comprise locations in their historic and more recently occupied range near their northern range boundary. Spawning started later in the northern extreme of our study but also ended earlier, leading to decreased spawning duration from south to north. Spawning phenology was mostly driven by Julian day followed by temperature and latitude. Gonadosomatic index, a proxy for reproductive output, was lower in the northern region, indicating that black sea bass did not compensate for the shorter spawning season there. Hepatosomatic index was lower in the northern regions indicating lower pre-spawning liver energy reserves, potentially leading to lower reproductive output. These results suggest a potential for lower recruitment in the recently occupied range and should be further investigated to predict the impacts of ocean warming and for proactive fisheries management as black sea bass distributional range expands poleward. [ABSTRACT FROM AUTHOR]

Hepcidins are small cysteine-rich antimicrobial peptides that play a vital role in immunity against pathogen invasion. Here, a hepcidin (Cshep) from Centropristis striata was described, which is considered as a valuable aquaculture marine species in China. The open reading frame consisted of 273 bp. Eight conserved cysteine residues were identified. Phylogenetic analysis showed that Cshep had a relatively close relationship with the hepcidin from Epinephelus moara. Quantitative real-time PCR analysis demonstrated that Cshep was highly expressed in liver and significantly up-regulated when challenged with Vibrio harveyi. In addition, the synthetic Cshep peptide had a high antimicrobial activity against V. harveyi, but low against other pathogenic bacteria tested in this study. The killing kinetics analysis revealed that Cshep had a fast bactericidal effect on V. harveyi. These results suggested that Cshep may be involved in the immune response of C. striata against V. harveyi infection. [ABSTRACT FROM AUTHOR]

A self-developed gas explosion experimental system was used to detonate methane/air mixtures of different concentrations by different ignition methods, and the propagation processes of spherical flames and irregular flames formed by the explosions were recorded using a high-speed camera. Based on image processing and the fractal interpolation method, the propagation velocity of the explosion-stretched flame was calculated. The flame image was processed in MATLAB to optimize the traditional calculation method. Based on fractal theory, a fractal interpolation function was constructed to calculate the propagation velocity at each point on the front of the spherical stretched flame, and then, the laminar combustion velocity of the methane/air mixed balloon flame was obtained. Compared with the numerical simulation and empirical formula, the error in the laminar flame velocity was less than 0.2%, which verifies the correctness of the image processing and fractal interpolation method to calculate the flame propagation velocity. Using this method, the propagation velocity of the irregular fold stretching flame of the methane/air mixture was calculated, and the propagation velocity at each point along the flame front was obtained. The reason why the flame speed of the gas explosion with a high-temperature source was higher than the flame speed of the gas explosion with an electric spark was preliminarily explained. [ABSTRACT FROM AUTHOR]

Black sea bass (BSB), Centropristis striata, inhabit continental shelf waters of the eastern United States and are a member of the family Serranidae comprising true sea basses and groupers. Highly sought by fishermen, BSB are sustainably managed with 2018 commercial and recreational catch quotas of 1,600 and 1,664 m.t. (3.52 and 3.66 million lb), respectively. Wild broodstock are easily caught and adapted to recirculating aquaculture systems (RASs). The initiation and duration of the spawning period are controlled by photothermal conditioning, and eggs and larvae have been produced from December through August. GnRHa (5–10 μg/g bw) implants are effective at inducing ovulation in post‐vitellogenic females (>500 μm mean oocyte diameter = MOD). Fertilized eggs (0.94 mm diameter) are obtainable by strip spawning, but volitional spawning may yield higher egg quality. Most BSB develop as females and then switch to male (protogynous hermaphrodites) after several years. Yolksac larvae (YSL, 0 day post‐hatching = 0 dph, 3.0 mm total length = TL) are reared to the post‐metamorphic stage in RASs using greenwater Nannochloropsis oculata and enriched rotifers (2–22 dph), Artemia nauplii (16–22 dph) and enriched metanauplii (23–36 dph), and co‐feeding microparticulate diets (55.5–59% crude protein (CP), 10–15% crude lipid (CL)) from 15 dph, with complete weaning by 36 dph. Environmental optima for larvae are temperature (19–22°C), salinity (28–36 g/L), light intensity (1,500 lx), and photoperiod (16 L: 8 D). Survival of YSL to 50 dph (1 g) averages 12–15%. Advanced fingerlings (mean wt. = 27 g) were stocked in 16 m3 RAS tanks (103 fish/m3) at 33 g/L and 21°C and fed a commercial diet (55% CP, 15% CL) reached mean marketable sizes of 454 g (1 lb), 568 g (1.25 lb), and 682 g (1.5 lb) in 17, 20.2, and 22.9 months post‐hatching, respectively, with high growth variation. Harvest biomass density was 55 kg/m3 and feed conversion ratio was 1.1–1.2. Pasteurellosis Photobacterium damsela infections during growout were controlled by lowering water temperature. Wholesale prices for whole‐on‐ice BSB (0.75 lb to >2.0 lb) are size‐tiered, with higher per pound prices for larger fish. BSB growers target niche markets for ultra‐fresh product, which garner premium prices for fish of assorted sizes. Availability of BSB fingerlings from the University of North Carolina Wilmington's hatchery has enabled startup RAS farmers to grow and to market BSB, but commercial expansion will require investment in research to lower production costs. Research is needed to lower feed and fingerling costs, increase growth and minimize size variation through grading and selective breeding, maximize biomass densities in RAS, and biomitigate RAS nutrients by multitrophic aquaculture. In‐depth economic modeling of BSB production in RAS incorporating the latest and untapped advances in culture technologies will be important to understand opportunities for improving profitability. [ABSTRACT FROM AUTHOR]

The present study is conducted to investigate the effect of dietary L-carnitine on growth performance and body compositions of Labeo calbasu fingerlings. 60 days feeding trial conducted. The L. calbasu fingerlings were fed with two level of L-carnitine 1 & 2 g kg-1 L-carnitine at 35% protein & 6% lipid, 30% protein & 9% lipid and 25% protein & 12% lipid. The result had shown that significant effect on growth performance and body composition. Highest weight gain percentage (WGP) 354.81±6.26, specific growth rate (SGR) 1.10±0.01 and protein efficiency ratio (PER) 1.91±0.02 in T1.2 group and lower feed conversion ratio (FCR) 1.41±0.02 in C3 group were recorded. Highest carcass protein (15.06±0.34) in T1.2 group and lowest carcass fat (3.12±0.14) in T1.2 group found. The present study demonstrates the dietary supplementation of both levels of L-carnitine have a positive effect on growth performance and body composition of L. calbasu fingerlings. [ABSTRACT FROM AUTHOR]

Foodborne enteric viruses, in particular HuNoV and HAV, are the most common cause of the berry-linked viral diseases, and outbreaks around the world, and have become an important concern for health authorities. Despite the increased importance of berry fruits as a vehicle for foodborne viruses, there is limited information concerning the fate of foodborne viruses in the berry supply chain from farm to consumer. A comprehensive understanding of berry-associated viral outbreaks – with a focus on contamination sources, persistence, survival, and the effects of current postharvest and processing interventions and practices – is essential for the development of effective preventative strategies to reduce risk of illness. The purpose of this paper is twofold; (i) to critically review the published literature on the current state of knowledge regarding berry-associated foodborne viral outbreaks and the efficiency of berry processing practices and (ii) to identify and prioritize research gaps regarding practical and effective mechanism to reduce viral contamination of berries. The review found that fecally infected food handlers were the predominant source of preharvest and postharvest pathogenic viral contamination. Current industrial practices applied to fresh and frozen berries demonstrated limited efficacy for reducing the viral load. While maintaining best practice personal and environmental hygiene is a key intervention, the optimization of processing parameters (i.e., freezing, frozen storage, and washing) and/or development of alternative processing technologies to induce sufficient viral inactivation in berries along with retaining sensory and nutritional quality, is also an important direction for further research. [ABSTRACT FROM AUTHOR]

Pursuant to the Canadian Environmental Protection Act (CEPA), a notification under the New Substances Notification Regulations (Organisms) (NSNR(O)) was submitted by AquaBounty Canada to Environment Canada (EC) for the commercial manufacture and export of the AquAdvantage™ Salmon (AAS), a transgenic Atlantic Salmon claimed to reach market size in half the time of a domesticated Atlantic Salmon. AquaBounty has indicated its intent to commercially produce all-female triploid, AAS eyed-eggs at their contained, land-based Prince Edward Island facility, for export to a contained, land-based grow-out facility in the highlands of Panama, where AAS will be grown to a commercial weight, and then processed for retail sale in approved markets as food. Fisheries and Oceans Canada (DFO) conducted an environmental and indirect human health risk assessment of AAS to support a regulatory decision by the Minister of the Environment and to underpin recommendations on measures necessary to manage risk. The risk assessment analyzed potential hazards, likelihood of exposure and associated uncertainties, to reach a conclusion on risk. The exposure assessment was based on a Failure Mode Analysis that focused on the potential for AAS to enter the Canadian environment, with activities in Panama only relevant where they may have resulted in AAS exposure to the Canadian environment. The assessment concludes with reasonable certainty that the likelihood of AAS exposure to the Canadian environment is negligible and that AAS is manufactured at a location where AquaBounty is able to contain AAS in a manner that satisfactorily protects the Canadian environment and human health. The indirect human health hazard assessment characterized the potential for AAS to cause adverse effects to humans in Canada, relative to wild Atlantic Salmon, as a consequence of environmental exposure. Potential human health hazards associated with AAS, including potential toxicity and allergenicity and the capacity of AAS to act as a vector for human pathogens, were considered. The assessment concludes with reasonable certainty that the risk to human health in Canada as a consequence of environmental exposure is low. The environmental hazard assessment characterized the nature and severity of the potential harmful effects that AAS may cause to the Canadian environment. Potential hazards associated with AAS, including the potential to affect wild populations, wild Atlantic Salmon predators, prey, competitors, and habitat, were considered. The assessment concludes with reasonable certainty that the risk to the Canadian environment is low. [ABSTRACT FROM AUTHOR]

Purpose: This update of our 2016 systematic review answers the following questions: (1) How often do older adults with cancer fall? (2) What are the predictors for falls? (3) What are the rates and predictors of injurious falls? (4) What are the circumstances and outcomes of falls? (5) How do falls in older patients affect subsequent cancer treatment? and a new research question, (6) Which fall reduction interventions are efficacious in this population? Methods: MEDLINE, PubMed, CINAHL, and Embase were searched (September 2015–January 25, 2019). Eligible studies included clinical trials and cohort, case-control, and cross-sectional studies published in English in which the sample (or subgroup) included adults aged ≥ 60, with cancer, in whom falls were examined as an outcome. Results: A total of 2521 titles were reviewed, 67 full-text articles were screened for eligibility, and 30 new studies were identified. The majority involved the outpatient setting (n = 19) utilizing cross-sectional method (n = 18). Sample size ranged from 21 to 17,958. Fall rates ranged from 1.52 to 3.41% per 1000 patient days (inpatient setting) and from 39%/24 months to 64%/12 months (outpatient setting). One out of the 6 research questions contributed to a new finding: one study reported that 1 in 20 older patients experienced impact on cancer treatment due to falls. No consistent predictors for falls/fall injuries and no studies on fall reduction interventions in the geriatric oncology setting were identified. Conclusion: This updated review highlights a new gap in knowledge pertaining to interventions to prevent falls. Additionally, new knowledge also emerged in terms of impact of falls on cancer treatment; however, further research may increase generalizability. Falls and fall-related injuries are common in older adults with cancer and may affect subsequent cancer treatment. Further studies on predictors of falls, subsequent impacts, and fall reduction in the oncology setting are warranted. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the biological development and growth of the Amur catfish, Silurus asotuss at the early larval stage. The eggs and larvae were obtained via the artificial spawning technique. The findings showed that the eggs of the Amur catfish hatched 27 hr after fertilization (hAF) under temperature conditions of 26.9 ± 1.3°C. The newly hatched larvae (4.71 ± 0.87 mm) had a large green yolk sac (0.99 ± 0.02 mm³), unpigmented eyes, undeveloped mouth, and closed anus with one pair of developed maxillary barbels. At the 30 hAH (7.01 ± 0.41 mm), the yolk sac continued to decrease (0.33 ± 0.08 mm³), the barbels elongated, the mouth opened, the lower jaw was movable, with the peristaltic movement of the small intestine detectable. At this point, the larvae started to feed on rotifer and formulated feed. At 72 hAH, larvae (9.02 ± 0.86 mm) had developed pectoral and dorsal fin and at 12 dAH (34.10 ± 0.89 mm) and entered the juvenile stage. This study concluded that the larval development and growth of the Amur catfish is relatively comparable to other tropical catfishes hence similar rearing techniques can be adopted to enhance the overall growth performance at the later stages. [ABSTRACT FROM AUTHOR]

The effects of photoperiod and temperature manipulation on reproductive cycles in threespine stickleback Gasterosteus aculeatus were examined. The experimental "advanced group" conditions were adjusted to simulate two reproductive seasons within a calendar year by adjusting light and temperature cycles. G. aculeatus subject to advanced conditions had two reproductive cycles per year, grew at normal rates and suffered little additional mortality. The research of many stickleback scientists would benefit from faster generation times and our methods could potentially shorten the time required to produce fish for genetic, behavioural and morphological work. [ABSTRACT FROM AUTHOR]

The present study was designed to examine the physiological responses of juvenile managua cichlid, Cichlasoma managuense under short‐term salinity stress, that is transferring C. managuense from freshwater to brackish water of salinity 0 (control group), 3‰, 6‰, 9‰, 12‰ or 15‰ for 48, 96, 144 and 192 hr respectively. The results showed that gill Na+/K+‐ATPase (NKA) activity revealed a decreased (48 hr), increased (96 hr) and then slightly decreased (144 hr, 192 hr) response with increasing salinity and the lowest NKA level was consistently detected at 9‰ salinity treatment; gill Ca2+/Mg2+‐ATPase (CMA) activities in all salinity treatments were significantly higher than that of the control group (p <.05) before 144 hr; the RNA/DNA ratio was significantly reduced when exposed to high salinities (≥9‰), suggesting growth inhibition; serum cortisol level gradually decreased at low salinities (up to 6‰) but dramatically increased at high salinities of 12‰ and 15‰; and both serum glucose/lactic acid levels and heat shock protein 90 (HSP90) level in liver/muscle were decreased at the salinity between 9‰ and 6‰ but increased at the salinity between 12‰ and 15‰, which was a U‐shape response curve. Taken together, our data suggest that C. managuense can adapt well at salinity up to 0‰–9‰ and high salinity may cause detrimental effects. [ABSTRACT FROM AUTHOR]