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The genomic DNA of a biotype 2 serovar E isolate (tester) is compared with the genomic DNAs of three biotype 1 strains by suppression subtractive hybridization and then tested the distribution of the tester-specific DNA sequences in a wide collection of bacterial strains. The main objective is to identify Vibrio vulnificus biotype 2-specific DNA sequences by suppression subtractive hybridization.

A 14-week trial was conducted to investigate the effects of antinutritional factors ( ANFs) commonly present in soybean ingredients, singly and in combination, on Atlantic salmon ( Salmo salar L.) fed from start-feeding. The experimental diets consisted of a negative control fish meal diet ( FM), and a positive control diet with 167 g kg−1 soybean meal inclusion ( SBM) and four diets based on the FM diet supplemented with 2 g kg−1 soya-saponins ( SAP), 1.5 g kg−1 isoflavones ( IFL), 0.3 g kg−1 phytosterols ( PHS) or a mixture of these ( MIX). Fish fed the SAP diet showed significantly higher growth performance than those fed FM, while the IFL treatment significantly decreased growth performance of salmon fry. Fish fed the IFL diet had significantly lower maltase activity and higher trypsin activity in proximal intestine than fish fed the FM diet. Histological differences were observed in the liver of fish fed the IFL diet, characterized by reduced size of the hepatocytes. Fish fed the PHS and IFL diets showed the highest frequencies of skeletal deformities among the six treatments. In conclusion, the results indicate that purified isoflavones may negatively affect growth performance, intestinal function, liver metabolism and bone formation of salmon fry. [ABSTRACT FROM AUTHOR]

Little is known about the functional consequences of triploidy in Atlantic cod. This study compared the gut morphology of diploid and triploid offspring of wild and selected broodstock. Three-year-old triploid offspring of wild cod (mean weight 1695 ± 346 g) had approximately 18% fewer pyloric caeca (125 ± 9 vs 172 ± 14, P < 0.001) and a 23% shorter intestine [Relative Gut Length, ( RGL); 1.40 ± 0.17 vs 1.81 ± 0.17, P < 0.05] than their diploid siblings (mean weight: 1820 ± 262 g). Two-year-old triploid offspring of selected broodstock (mean weight: 640 ± 64 g) had 20% fewer pyloric caeca (309 ± 17 vs 387 ± 27, P < 0.001) but similar RGL to their diploid siblings (mean weight: 820 ± 69 g). The average number of mucus cells in the columnar epithelium of pyloric caeca was significantly higher in triploid than in diploid cod (54 ± 9 vs 25 ± 5, P < 0.001). There was no correlation between pyloric caeca number and RGL, or between mucus cells and pyloric caeca number, and no significant differences between sexes for any of the measured variables. Overall, the observations highlight some differences in the digestive system of these two ploidy groups that could have an influence on nutrient utilization and performance capacity in triploids compared to diploids. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate the effects of two light regimes that independently had shown positive effects on feeding and growth in cultures of Atlantic halibut, Hippoglossus hippoglossus (L.), larvae. The regimes were low-intensity overhead light and submerged light at intermediate light intensities. Secondly, an alleged beneficial effect of algae was investigated. An experiment was designed to include four different regimes in the larval cultures: low-intensity overhead light with and without algae (Tetraselmis sp.), and submerged light with and without algae. The results showed that submerged light was superior to overhead light with respect to larval growth, survival and feeding incidence. It was further indicated that algae improved larval growth and survival, but no effect was shown on feeding incidence. There was, however, no interaction between the effects of algae and those of the light regime. The causal effect of the algae may be ascribed to indirect factors, such as light attenuation as well as a direct and indirect nutritional effect. [ABSTRACT FROM AUTHOR]

Sea lice (Lepeophtheirus salmonis [Krøyer, 1838]) are a key issue for salmon aquaculture, contributing to increased mortality for both wild and farmed salmon if no action is taken. Using cleaner fish can be an effective, drug-free treatment method, and ballan wrasse (Labrus bergylta) is a hardy wrasse species that displays cleaning behavior. With concerns about the overharvest of wild ballan wrasse, many companies farm this species, but the optimal ranges of a wide variety of rearing parameters are still unknown. This study investigated the effect of 6-week exposure to four dissolved oxygen (DO) levels (125%, 100%, 85%, and 75% DO saturation as the percentage of air) on ballan wrasse. Survival; growth (specific growth rate, SGR); condition factor (CF); and primary (cortisol), secondary (glucose, lactate, magnesium), and tertiary stress indicators (swimming performance) were investigated. There were no differences in SGR, CF, survival, or cortisol level among the groups at the end of the 6 weeks. There was variation in the magnitude of the cortisol response to an acute stressor at the end of the 6-week period, with the 75% DO treatment exhibiting a 3.3-fold increase in cortisol compared to a 5.2-fold increase in the control group (100%), which could suggest chronic stress. Relative critical swimming speed (RU crit ) was measured to investigate swimming performance once all groups were returned to 100% DO saturation. The 75% RU crit was lower than the 100% treatment (1.7 ± 0.18 body length [BL]/s compared to 2.5 ± 0.16 BL/s). Overall, these results suggest that DO levels of 75% trigger physiological changes and therefore may negatively affect welfare., (© 2024 Fisheries Society of the British Isles.)

Cleaner fish species have gained great importance in the control of sea lice, among them, lumpfish (Cyclopterus lumpus) has become one of the most popular. Lumpfish life cycle has been closed, and hatchery reproduction is now possible, however, current production is reliant on wild caught broodstock to meet the increasing demand. Selective breeding practices are called to play an important role in the successful breeding of most aquaculture species, including lumpfish. In this study we analysed a lumpfish population for the identification of genomic markers linked to production traits. Sequencing of RAD libraries allowed us to identify, 7193 informative markers within the sampled individuals. Genome wide association analysis for sex, weight, condition factor and standard length was performed. One single major QTL region was identified for sex, while nine QTL regions were detected for weight, and three QTL regions for standard length. A total of 177 SNP markers of interest (from QTL regions) and 399 high F st SNP markers were combined in a low-density panel, useful to obtain relevant genetic information from lumpfish populations. Moreover, a robust combined subset of 29 SNP markers (10 associated to sex, 14 to weight and 18 to standard length) provided over 90% accuracy in predicting the animal's phenotype by machine learning. Overall, our findings provide significant insights into the genetic control of important traits in lumpfish and deliver important genomic resources that will facilitate the establishment of selective breeding programmes in lumpfish., Competing Interests: Declaration of Competing Interest T.C.R. and E.J.F. are employed by Otter Ferry SeaFish Ltd., a funding partner of the research project. The other authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Concerns have long been raised about the welfare of ballan wrasse (Labrus bergylta) used for the biological control of sea lice in Atlantic salmon (Salmo salar) aquaculture. This study assessed the effect of increased dietary eicosapentaenoic acid (EPA) levels and initial condition factor (CF) on the subsequent performance and welfare of ballan wrasse farmed in high and low water temperatures. Fish were fed a diet with either commercial or high EPA levels for 3 months at 15°C. Subsequently, fish were tagged with a passive integrated transponder, measured for their CF and divided into two groups consisting of fish from both treatments and reared for 4.5 months at either 15 or 6°C fed a commercial diet. Each fish was categorized as high (≥2.7) or low CF (<2.7) fish based on the calculated average CF of the population. Dietary composition influenced the fatty acid (FA) profile of the stored lipids without affecting the growth or welfare of ballan wrasse. Fish reared at 15°C showed higher growth, more fat and energy reserves and less ash content. Fish reared at 6°C lost weight, using up their body lipids at the end of the temperature trial. Gene expression analyses showed upregulation of the positive growth marker (GHrα) and two genes involved in the synthesis and oxidation of FAs (elovl5, cpt1) and downregulation of the negative growth marker (mstn) in fish reared at 15°C compared to those reared at 6°C. Fish reared at 6°C showed upregulated levels of il-6 compared to those reared at 15°C, suggesting an enhanced immune reaction in response to low temperature. Fish with high CF showed better survival, growth and performance compared to those with low CF. External welfare scoring showed higher prevalence and severity in emaciation, scale loss and the sum index score (of all measured welfare parameters) in fish reared at 6°C compared to those reared at 15°C and better welfare in fish with high CF compared to those with low CF. Histological examination of the skin showed that fish reared at 6°C had decreased epidermal thickness, a lower overall number of mucous cells in the inner and outer epidermis and a different organization of mucous cells compared to fish reared at 15°C, indicating stress in fish reared at 6°C. Overall, low water temperatures had profound effects on the performance and external and internal welfare parameters of ballan wrasse and can be considered a stressor likely affecting the delousing efficacy. These findings support the seasonal use of different cleaner fish species. High CF, but not increased dietary EPA levels, appeared to help fish cope better with low water temperatures and should thus be assessed and considered before deploying them in salmon cages., (© 2023 The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of Fisheries Society of the British Isles.)

A 5-week feeding trial was conducted in the cleaner fish Ballan wrasse ( Labrus bergylta ) for a better understanding of the basic biology of the intestinal functions and health in this stomach less species. During the trial, Ballan wrasse was fed either a reference diet, the reference diet supplemented with (i) a commercial prebiotic (Aquate™ SG, 0·4 %) expected to have beneficial effects, (ii) soya saponins (0·7 %) expected to induce inflammation or (iii) a combination of the prebiotics and the soya saponins to find a remedy for gut inflammation. Blood, intestinal tissue and gut content from four consecutive intestinal segments (IN1 - IN4) were collected. No significant differences in fish growth were observed between the four dietary groups. Saponin supplementation, both alone and in combination with prebiotics, increased weight index of IN2 and IN3 and decreased blood plasma glucose, cholesterol and total protein. Dry matter of intestinal content and activity of digestive enzymes were not affected by diet. Histomorphological analyses revealed a progressing inflammation with increased infiltration by immune cells particularly into the distal parts of the intestine in fish fed diets with saponins, both alone and in combination with prebiotics. Gene expression profiles obtained by RNA sequencing and quantitative PCR mirrored the histological and biochemical changes induced by the saponin load. The study demonstrated that Ballan wrasse gut health and digestive function may be markedly affected by feed ingredients containing antinutrients.

Background: Cancer risk assessment should stratify screening and enable preventive health interventions based on individuals' risk of developing cancer. Studies are underway to develop epigenetic tests, including trials investigating women's risk of female-specific cancers., Objective: Given potential consequences for quality of life and care, women considering such assessment need to be able to make a fully informed choice. It is currently unknown what information they require., Method: We conducted 4 focus groups with 25 women (aged 30-65 years) to explore what they want to know about epigenetic cancer risk assessment, how they evaluate its usefulness, and how they would like to be informed about their risk. Independent coders categorised paraphrases based on transcribed recordings of the group discussions to enable a summarising text analysis., Results: The women in the study wanted to understand how the epigenetic approach is different from established genomic tests, how epigenetic changes relate to cancer, and whether the test enables monitoring of one's cancer risk (n = 11). Furthermore, they desired information about their basic cancer risks (n = 11), about the quality of the assessment (n = 9), and about measures to deal with a risk result (n = 11)., Conclusions: Informed consent in epigenetic cancer risk assessments depends on whether basic cancer risks, uncertainties of testing, and effects of tests on care management are transparently communicated prior to testing. These requirements are not limited to epigenetic testing. Accordingly, physicians and health authorities will have to provide multi-layered information when counselling women on cancer risk assessment., (© 2019 S. Karger AG, Basel.)

Objectives: Informed decisions about cancer screening require accurate knowledge regarding cancer risks and screening. This study investigates: (1) European women's knowledge of their risk of developing breast, ovarian, cervical or endometrial cancer, (2) their knowledge about mammography screening and (3) whether an evidence-based leaflet improves their knowledge., Design: Cross-sectional online intervention survey., Setting: National samples from five European countries (Czech Republic, Germany, UK, Italy and Sweden)-drawn from the Harris Interactive and the Toluna panel, respectively, in January 2017-were queried on their knowledge of age-specific risks of developing breast, cervical, ovarian or endometrial cancer within the next 10 years and of mammography screening before and after intervention., Participants: Of 3629 women (inclusion criteria: age 40-75 years) invited, 2092 responded and 1675 completed the survey (response rate: 61.4%)., Intervention: Evidence-based leaflet summarising information on age-adjusted female cancer risks, mammography and aspects of cancer prevention., Primary Outcome Measures: Proportion of women (1) accurately estimating their risk of four female cancers, (2) holding correct assumptions of mammography screening and (3) changing their estimations and assumptions after exposure to leaflet., Findings: Across countries, 59.2% (95% CI 56.8% to 61.6%) to 91.8% (95% CI 90.3% to 93.0%) overestimated their female cancer risks 7-33 fold (medians across tumours : 50.0 to 200.0). 26.5% (95% CI 24.4% to 28.7%) were aware that mammography screening has both benefits and harms. Women who accurately estimated their breast cancer risk were less likely to believe that mammography prevents cancer (p<0.001). After leaflet intervention, knowledge of cancer risks improved by 27.0 (95% CI 24.9 to 29.2) to 37.1 (95% CI 34.8 to 39.4) percentage points and of mammography by 23.0 (95% CI 21.0 to 25.1) percentage points., Conclusion: A considerable number of women in five European countries may not possess the prerequisites for an informed choice on cancer screening. Evidence-based information in patient leaflets can improve this situation., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Despite a long history of rearing Atlantic salmon in hatcheries in Norway, knowledge of molecular and physiological aspects of juvenile development is still limited. To facilitate introduction of alternative feed ingredients and feed additives during early phases, increased knowledge regarding the ontogeny of the digestive apparatus in salmon is needed. In this study, we characterized the development of the gastrointestinal tract and accessory digestive organs for five months following hatch by using histological, biochemical and molecular methods. Furthermore, the effects of a diet containing 16.7% soybean meal (SBM) introduced at start-feeding were investigated, as compared to a fishmeal based control diet. Salmon yolk sac alevins and fry were sampled at 18 time points from hatch until 144 days post hatch (dph). Histomorphological development was investigated at 7, 27, 46, 54 and 144 dph. Ontogenetic expression patterns of genes encoding key digestive enzymes, nutrient transporters, gastrointestinal peptide hormones and T-cell markers were analyzed from 13 time points by qPCR. At 7 dph, the digestive system of Atlantic salmon alevins was morphologically distinct with an early stomach, liver, pancreas, anterior and posterior intestine. About one week before the yolk sac was internalized and exogenous feeding was started, gastric glands and developing pyloric caeca were observed, which coincided with an increase in gene expression of gastric and pancreatic enzymes and nutrient transporters. Thus, the observed organs seemed ready to digest external feed well before the yolk sac was absorbed into the abdominal cavity. In contrast to post-smolt Atlantic salmon, inclusion of SBM did not induce intestinal inflammation in the juveniles. This indicates that SBM can be used in compound feeds for salmon fry from start-feeding to at least 144 dph and/or 4-5 g body weight.

Responses in Atlantic salmon (Salmo salar L.) juveniles (fry) fed diets containing genetically modified maize (Bt-maize, MON810) expressing Cry1Ab protein from first-feeding were investigated during a 99-day feeding trial. Four experimental diets were made; each diet contained ∼20% maize, either Bt-maize or its near-isogenic maternal line (non-GM maize). One pair was fishmeal-based while the other pair included standard (extracted) soybean meal (SBM; 16.7% inclusion level), with the intention of investigating responses to the maize varieties in healthy fish as well as in immunologically challenged fish with SBM-induced distal intestinal inflammation, respectively. Three replicate tanks of fry (0.17±0.01 g; initial mean weight ± SEM) were fed one of the four diets and samples were taken on days 15, 36, 48 and 99. Survival, growth performance, whole body composition, digestive function, morphology of intestine, liver and skeleton, and mRNA expression of some immune and stress response parameters in the distal intestine were evaluated. After 99 days of feeding, survival was enhanced and the intended SBM-induced inflammatory response in the distal intestine of the two groups of SBM-fed fish was absent, indicating that the juvenile salmon were tolerant to SBM. Mortality, growth performance and body composition were similar in fish fed the two maize varieties. The Bt-maize fed fish, however, displayed minor but significantly decreased digestive enzyme activities of leucine aminopeptidase and maltase, as well as decreased concentration of gut bile salts, but significantly increased amylase activity at some sampling points. Histomorphological, radiographic and mRNA expression evaluations did not reveal any biologically relevant effects of Bt-maize in the gastrointestinal tract, liver or skeleton. The results suggest that the Cry1Ab protein or other compositional differences in GM Bt-maize may cause minor alterations in intestinal responses in juvenile salmon, but without affecting overall survival, growth performance, development or health.

Thioglycollate-elicited peritoneal M phi of mice were treated with calcium ionophore A23187 prior to incubation with tumor cells. Supernatants prepared from the incubation mixtures were assayed for their effects on incorporation of 3H-thymidine into tumor cells. Significant inhibition of incorporation was observed in most instances. Ingestion of indomethacin in the drinking water for 7 days by prospective M phi donors increased the inhibition by supernatants. The activity of the supernatants was neither specific for the strain and sex of M phi donors nor correlated with the genotype of the tumors. The activity even crossed the species barrier inasmuch as inhibitory supernatants were produced by murine M phi incubated with either murine or human tumor cells. Supernatants derived from murine as well as human tumor cells significantly depressed thymidine incorporation into murine and human tumor cells, although there were some differences in the response of the two kinds of tumor cells. In rare instances, supernatants enhanced, rather than inhibited, thymidine incorporation. Moreover, when supernatants, added to tumor cells, were removed and replaced by fresh medium, in most instances, significant enhancement of thymidine incorporated occurred. The formation of both growth-inhibiting and growth-promoting factors by M phi in the in vitro model used in this study, may explain the dual role of M phi in neoplasia in vivo.

Recently we demonstrated a strong induction of activin expression after skin injury, suggesting a function of this transforming growth factor-beta family member in wound repair. To test this possibility, we generated transgenic mice that overexpress the activin betaA chain in the epidermis under the control of a keratin 14 promoter. The transgenic mice were significantly smaller than control littermates, and they had smaller ears and shorter tails. In their skin, the fatty tissue was replaced by connective tissue and a severe thickening of the epidermis was found. The spinous cell layer was significantly increased, and the epidermal architecture was highly disorganized. These histological abnormalities seem to result from increased proliferation of the basal keratinocytes and abnormalities in the program of keratinocyte differentiation. After skin injury, a significant enhancement of granulation tissue formation was detected in the activin-overexpressing mice, possibly as a result of premature induction of fibronectin and tenascin-C expression. These data reveal novel activities of activin in the regulation of keratinocyte proliferation and differentiation as well as in dermal fibrosis and cutaneous wound repair.

The antitumour activity of peritoneal macrophages, added to tumour inocula (Winn test), was determined. Macrophages harvested from mice immunised with tumour, or from tumour-bearing mice, suppressed or inhibited tumour growth when in direct contact with tumour cells. Incubation of macrophages exhibiting antitumour activity with tumour cells yielded supernatant fluids capable of interfering with tumour growth. Consistent induction of antitumor activity required either addition of indomethacin to the incubation mixture, or collection of macrophages from immunised or tumour-bearing donors that had ingested indomethacin in the drinking water. Tumour growth was significantly inhibited when tumour inocula were suspended in supernatant fluid, or when mice were given several subcutaneous injections of supernatant prior to tumour transplantation.