Search

Background: A scoping review found that most studies on women's health in multiple sclerosis (MS) focused on pregnancy, fetal/neonatal outcomes and sexual dysfunction. Few studies addressed menopause, contraception, gynecologic cancers/cancer screening. However, the perceived relative importance of these knowledge gaps to people living with MS and other partners is unknown. We engaged a range of partners, including people living with MS, health care providers, researchers, and patient advocacy groups, to set priorities for future research in women's health in MS. Methods: We employed a three-step global engagement process. First, we identified which broad research topics relevant to women's health in MS were of highest priority using two surveys. Second, we developed specific research questions within these topics using focus groups. Finally, we prioritized the research questions with a third survey. Results: Overall, 5,266 individuals responded to the initial surveys [n = 1,430 global survey, mean (SD) age 50.0 (12.6), all continents; n = 3,836 North American Research Committee on Multiple Sclerosis survey, mean (SD) age 64.8 (9.6), United States]. Menopause, sexual dysfunction, pregnancy, gynecologic cancer/cancer screening, hormones and parenthood were identified as the most important topics. Focus groups generated 80 potential research questions related to these topics. In the final survey 712 individuals prioritized these questions. The highest priority questions in each research topic were: (i) How do perimenopause and menopause affect disease activity, course, response to disease-modifying treatment and quality of life in MS; (ii) What are the most effective strategies for managing issues around sexual intimacy, including related to low sexual desire, changes in physical function, and MS symptoms; (iii) Are there long-term effects of disease-modifying therapies on the children of persons with MS; (iv) What are the short and long-term effects of disease-modifying drugs on gynecologic cancer risk, particularly for high efficacy disease-modifying drugs and hematopoietic stem cell transplantation; (v) Are there hormone related treatments that can stabilize fluctuations in MS symptoms; and (vi) How does MS fatigue impact parenting strategies. Conclusion: Priorities for research relating to women's health issues for persons with MS have been delineated using a collaborative process with key partners. Alignment of future research with these priorities should be monitored. [ABSTRACT FROM AUTHOR]

We developed a DNA vaccine that induces the formation of a VLP in vivo. This VLP was designed to elicit neutralizing antibodies, to induce better T-cell responses and to activate the innate immune system. Overall, 5 groups of 10 mice were electroporated with the following constructs: pVLP-LTR-GagPro [full], pVLP-GagPro [VLP wihout RNA], pVLP-LTR-Gag [VLP immature], pVLP-Gag and pVLP-EnvBG505 [regular DNA vaccine] and a mock group. We performed ICS on the mouse spleens and performed ELISA for ENV antibodies and a Luminex assay for inflammatory cytokines. The VLP showed good binding to the neutralizing antibodies. The percentage of CD4 cells producing cytokines was 0.1% [IFNg], 0.15%[IL-2] and 0.2% [TNFa] for the construct pVLP-LTR-GagPro. The percentage of CD8 cells producing cytokines was 0.3%[IFNg], 0.2%[IL-2] and 0.25%[TNFa]. All pVLP constructs induced more antibodies for EnvBG505 than the regular DNA vaccine Env. The pVLP-LTR-GagPro induced more IL-1B than the other constructs 24 hours post-vaccination.

Amphibians have undergone dramatic declines and extinctions worldwide. Prominent among these have been the stream-breeding frogs in the rainforests of eastern Australia. The amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd) has been postulated as the primary cause of these declines. We conducted a capture-mark-recapture study over a 7-year period on the endangered Fleay's barred frog (Mixophyes fleayi) at two independent streams (30 km apart) in order to assess the stability of these populations. This species had undergone a severe decline across its narrow geographic range. Mark-recapture modelling showed that the number of individuals increased 3-10 fold along stream transects over this period. Frog detection probabilities were frequently above 50% but declined as the populations increased. Adult survival was important to overall population persistence in light of low recruitment events, suggesting that longevity may be a key factor in this recovery. One male and female were present in the capture record for >6 years. This study provides an unambiguous example of population recovery in the presence of Bd.

Background: Women with multiple sclerosis (MS) may face challenges related to managing reproduction, pregnancy, and menopause while simultaneously managing their disease. The purpose of this scoping review was to map the literature broadly related to topics relevant to women's health in MS to inform the clinical and research communities about the existing types and sources of evidence and knowledge gaps. Apart from coverage of topics within the field of women's health, we were interested in potential gaps related to geographic and racial and ethnic diversity. We also aimed to understand the degree of inclusion of women with progressive MS in this research. Methods: We searched the EMBASE and Ovid Medline databases from 1980 until November 23, 2020. We included case-control and cohort studies, clinical trials and case series published in any language, conducted in women with MS, clinically isolated syndrome, or radiologically isolated syndrome, that addressed women's health. Two reviewers independently screened abstracts and full-text reports for study inclusion, and completed data extraction. Results: Of 112,106 citations screened, 1,041 underwent full-text review and 353 met the inclusion criteria. The number of studies regarding women's health has increased exponentially over time. Almost half of the studies were conducted (at least in part) in Europe, while 21.7% were conducted in North America; only one study was conducted in Africa. Most studies did not report the race or ethnicity of their participants (n = 308, 87.2%). Among the 353 studies, 509 topics were reported as some studies addressed more than one topic. Over one-third of these focused on pregnancy (n = 201, 37.2%), followed by fetal/neonatal outcomes (14.4%) and sexual dysfunction (10%). Among the 201 studies that focused on pregnancy, only 51 (25.4%) included participants with progressive MS. Conclusions: This review identifies important knowledge gaps related to women's health in MS and particularly the need for future studies to include participants with a broader range of races and ethnicities, with progressive MS, and living in Asia-Pacific and African regions. [ABSTRACT FROM AUTHOR]

Large lakes throughout the world offer development opportunities for cage aquaculture. However, due to their vast area, identifying the most suitable locations can be a challenge. This is also complicated as lake systems are often multi‐use environments, so a strategic approach to managing the resource is required. This study uses geographic information systems (GIS) to develop a broad‐scale approach that identifies potential areas that may be suitable for cage aquaculture development. Volta Lake, one the world's largest man‐made lakes, is used as a case study. The overall GIS model combines four sub‐models, bathymetry, hydrography, water quality and access, and a constraints layer, to identify the most suitable locations for tilapia production. Three different cage sizes are modelled: small, medium and large. The model outputs suggest that approximately 102 km2 (1.7%), 406 km2 (6.9%) and 407 km2 (6.9%) of Volta Lake can be categorized as highly suitable for development of small, medium and large cages respectively. A further 634 km2 (10.8%), 1264 km2 (21.4%) and 1055 km2 (17.9%) can be categorized as suitable for the same. The results can be used by stakeholders and decision makers to identify specific areas where aquaculture development for cage farming of tilapia could be prioritized. [ABSTRACT FROM AUTHOR]

Background:Teleneurology has been well described for acute stroke, but outpatient use has been limited. At home, virtual visits have the potential to improve access to neurological care. Introduction:This study reports on the use of a personal device videoconferencing platform for outpatient neurologic follow-up visits. Materials and Methods:This is a cross-sectional study that identified all virtual neurologic follow-up visits completed by patients ≥18 years at a single institution over 4 years. Virtual visits were conducted by personal smartphone or computer via videoconferencing with a provider. Patients were asked to rate their overall experience with the visit and provider (five-point scale). Travel distance from the institution was calculated using patient's home addresses. Results:Three thousand nine hundred thirteen patients completed 5,581 virtual visits during the study (mean age 49.4 ± 17.0 years, 58.7% female). Number of virtual visits increased from 30 in year 1 to 4,468 in year 4. Virtual visits were completed in all outpatient neurologic subspecialties. A total of 30.1% of patients were local (<50 miles), 25.9% were near regional (50–150 miles), 21.7% were far regional (151–270 miles), and 22.2% were remote (>270 miles). A distance of 1,327,128 miles of travel was prevented across the 5,581 visits. On average, patients rated their overall virtual visit experience 4.7/5 ± 0.89 and rated their provider 4.9/5 ± 0.48. Discussion:Virtual visits prevented a substantial amount of travel and resulted in high patient satisfaction. The sizable proportion of local patients may indicate that teleneurology provides important access for reasons beyond travel distance. Conclusion:This study demonstrates the feasibility of implementing outpatient teleneurology services. [ABSTRACT FROM AUTHOR]

We describe the largest‐to‐date single‐center implementation of tele‐epilepsy. Beginning in 2017, all patients at a single tertiary care academic epilepsy center were offered the option to complete outpatient follow‐up visits via video‐conferencing using personal devices. A retrospective review of all patients who self‐selected virtual visits over nearly 3 years showed 2140 patients completed 3698 tele‐epilepsy visits, with 41% completing more than one visit during the study period. Based on the distance from the center to the home address, 26.7% of patients were local (≤50 miles), 30.5% were near regional (51‐150 miles), 20.1% were far regional (151‐270 miles), and 22.7% were remote (>270 miles), from 43 different states. An estimated 928 696 miles of travel was prevented, with a median travel distance saved of 124.5 miles (interquartile range = 45.0‐253.0). The mean visit time was 15.7 (±10.4) minutes. More than 90% of patients gave the visit and provider experience the maximum rating, with a nearly 60% response rate on the post‐visit survey. Virtual outpatient follow‐up care provides a convenient way to connect with epilepsy specialists and reduce the burden of care by cutting travel time. Our experience demonstrates that outpatient tele‐epilepsy is feasible, sustainable, and scalable. [ABSTRACT FROM AUTHOR]

There are many spatial issues associated with aquaculture which must be understood in order to support sustainable development and mitigate other potential issues. Geographic Information Systems (GIS) are used for investigation, analysis and modelling of aquaculture and there have been a considerable number of studies since the late 1980s. However, despite the range of applications, GIS is still often underutilized and stakeholders have requested more GIS‐based tools to support management and regulation of the sector. Consequently, there is a need to establish a knowledge base of existing applications and identify the challenges and opportunities to encourage development of tools that address user needs. This study presents a quantitative analysis of primary scientific literature, focusing on over 200 studies, to enable a comprehensive overview of the application of GIS and the trends associated with its use for aquaculture. Furthermore, there is a detailed assessment of the considerations when developing GIS‐based tools for aquaculture which culminates in five key recommendations regarding (i) usability of the tool; (ii) data requirements; (iii) accessibility to end user; (iv) capabilities and training requirements; and (v) longevity of the tool. These recommendations can guide future development and application of tools to support aquaculture planning and management and assess spatial issues relevant for the sector. [ABSTRACT FROM AUTHOR]

This study involved the determination of sediment quality and heavy metals in the water column and bottom sediment of a selected cage fish farm in Lake Volta, to assess the potential impact of metals and organic matter pollution on the lake due to cage fish farming. Sediment analysis indicated that the texture of all sampling sites was sandy clay loam with sand dominating with a range of 31.5%–81.2%. The organic matter (TOM) ranged from 4.42%–8.89%, while organic carbon (TOC) was from 2.57%–5.22%. Total nitrogen (TN) fluctuated between 0.22% and 0.45%; total phosphate ranged between 0.22% and 5.30%. The TOC, TOM and TN content in the farm sediment were significantly lower than those of the reference sites (ANOVA, p <.05). Lead, copper, cadmium and selenium were not detected in the water. The results revealed that heavy metal concentrations in the water column and sediments were low and within tolerable levels, indicating no influence of metals from fish feed was observed on the lake water quality. However, the farm seemed to have moderate impact on sediment quality from organic matter. Water and sediment quality monitoring should be embarked upon periodically to ensure sustainable cage culture in the Lake Volta. [ABSTRACT FROM AUTHOR]

Background: Systematic measurement of conversational features in the natural clinical setting is essential to better understand, disseminate, and incentivize high quality serious illness communication. Advances in machine-learning (ML) classification of human speech offer exceptional opportunity to complement human coding (HC) methods for measurement in large scale studies. Objectives: To test the reliability, efficiency, and sensitivity of a tandem ML-HC method for identifying one feature of clinical importance in serious illness conversations: Connectional Silence. Design: This was a cross-sectional analysis of 354 audio-recorded inpatient palliative care consultations from the Palliative Care Communication Research Initiative multisite cohort study. Setting/Subjects: Hospitalized people with advanced cancer. Measurements: We created 1000 brief audio "clips" of randomly selected moments predicted by a screening ML algorithm to be two-second or longer pauses in conversation. Each clip included 10 seconds of speaking before and 5 seconds after each pause. Two HCs independently evaluated each clip for Connectional Silence as operationalized from conceptual taxonomies of silence in serious illness conversations. HCs also evaluated 100 minutes from 10 additional conversations having unique speakers to identify how frequently the ML screening algorithm missed episodes of Connectional Silence. Results:Connectional Silences were rare (5.5%) among all two-second or longer pauses in palliative care conversations. Tandem ML-HC demonstrated strong reliability (kappa 0.62; 95% confidence interval: 0.47–0.76). HC alone required 61% more time than the Tandem ML-HC method. No Connectional Silences were missed by the ML screening algorithm. Conclusions: Tandem ML-HC methods are reliable, efficient, and sensitive for identifying Connectional Silence in serious illness conversations. [ABSTRACT FROM AUTHOR]

Eggs and larvae of axolotls are susceptible to fungal infections in culture, producing high mortalities that could be prevented by the use of saline media. Newly hatched larvae of Anderson's salamander Ambystoma andersoni were exposed to seven salinities (0, 5, 10, 15, 20, 25, and 30‰) to observe the effect on survival. Newly hatched larvae did not tolerate more than 10‰ salinity during short‐term exposure. Survival and growth of newly hatched larvae were then assessed at 0, 5, and 10‰ over a 6‐week period. Larval survival and growth were greater at 5‰ than in the 0‰ control. Survival, growth, and proximate composition of 60‐d‐old juveniles were compared between 0‰ and 5‰. The 60‐d‐old juveniles performed better in 0‰, and there was no significant difference in proximate analysis between treatments. This work shows that salinity can be used to improve survival and growth in Anderson's salamander larvae, as they can tolerate up to 10‰ immediately after hatching, and 2‐month‐old larvae survive and grow well in salinities of up to 5‰. [ABSTRACT FROM AUTHOR]

Abstract: The endemic Mexican silversides of Lake Pátzcuaro (Pike Silverside Chirostoma estor) and Lake Chapala (Blacknose Silverside C. promelas) are endangered fish species of great socioeconomic importance in the region. Since the last decade, much progress has been made to close the life cycle in captivity and in promoting the aquaculture of these species. The lack of standardized husbandry and broodstock management practices, including sex discrimination, is a bottleneck to the commercial culture of these species. Recent observations have suggested a possible difference between the length of the pelvic fins of males and females. To explore these observations, biometric measurements were taken from Pike Silverside and Blacknose Silverside broodstocks, comprising body weight, SL, distance from the base of the pelvic fin to the genital pore (BPF), and distance from the tip of pelvic fin to the genital pore (TPF). The latter measurements were used to calculate the TPF/BPF ratio. Sex‐specific differences were found in BPF, TPF, and TPF/BPF for both species, clearly indicating a sexually dimorphic characteristic not previously reported in any atherinopsid. This study reveals for the first time the presence of a noticeable sexually dimorphic and externally evident trait in two closely related atherinopsid species, which provides a simple morphometric technique for sex discrimination that minimizes manipulation and thus avoids overstressing or killing the fish. [ABSTRACT FROM AUTHOR]

There is now a strong consensus that during the 20th century, and especially during recent decades, the earth has experienced a significant warming trend with projections suggesting additional further warming during the 21st century. Associated with this warming trend are changes in climate that are expected to show substantial spatial variability across the earth's surface. Globally, fish production has continued to increase during recent years at a rate exceeding that of human population growth. However, the contribution from capture fisheries has remained largely static since the late 1980s with the increase in production being accounted for by dramatic growth in the aquaculture sector. In this study, the distribution of vulnerability of aquaculture-related livelihoods to climate change was assessed at the global scale based on the concept of vulnerability as a function of sensitivity to climate change, exposure to climate change and adaptive capacity. Use was made of national-level statistics along with gridded climate and population data. Climate change scenarios were supplied using the MAGICC/ SCENGEN climate modelling tools. Analysis was conducted for aquaculture in freshwater, brackish and marine environments with outputs represented as a series of raster images. A number of Asian countries (Vietnam, Bangladesh, Laos and China) were indicated as most vulnerable to impacts on freshwater production. Vietnam, Thailand, Egypt and Ecuador stood out in terms of brackish water production. Norway and Chile were considered most vulnerable to impacts on marine production while a number of Asian countries (China, Vietnam and the Philippines) also ranked highly. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Biologia Marina y Oceanografía (RBMO) is the property of Universidad de Valparaiso, Facultad de Ciencias del Mar and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Large yellow croaker (LYC) cage farming is a rapidly developing industry in the coastal areas of the East China Sea. However, little is known about the environmental nutrient loadings resulting from the current aquaculture practices for this species. In this study, a nitrogenous waste model was developed for LYC based on thermal growth and bioenergetic theories. The growth model produced a good fit with the measured data of the growth trajectory of the fish. The total, dissolved and particulate nitrogen outputs were estimated to be 133, 51 and 82 kg N tonne of fish production, respectively, with daily dissolved and particulate nitrogen outputs varying from 69 to 104 and 106 to 181 mg N fish, respectively, during the 2012 operational cycle. Greater than 80 % of the nitrogen input from feed was predicted to be lost to the environment, resulting in low nitrogen retention (<20 %) in the fish tissues. Ammonia contributed the greatest proportion (>85 %) of the dissolved nitrogen generated from cage farming. This nitrogen loading assessment model is the first to address nitrogenous output from LYC farming and could be a valuable tool to examine the effects of management and feeding practices on waste from cage farming. The application of this model could help improve the scientific understanding of offshore fish farming systems. Furthermore, the model predicts that a 63 % reduction in nitrogenous waste production could be achieved by switching from the use of trash fish for feed to the use of pelleted feed. [ABSTRACT FROM AUTHOR]

We used a response-surface analysis to determine the importance of different factors affecting the resting routine metabolic rate (QO2) of the white shrimpLitopenaeus vannamei. The oxygen consumption rates were estimated using a multi-factorial design with 28 combinations of different salinities (15, 20, 25, 30, 35, 40 and 45 psu) and temperature (20, 25, 30 and 35 °C) values. The response-surface analysis produced a quadratic function showing that temperature more profoundly affects the oxygen consumption rate. Response-surface curves were generated to predict the optimal conditions resulting in oxygen consumption to better understand the successful growth of this species. [ABSTRACT FROM PUBLISHER]

Amphibians have undergone dramatic declines and extinctions worldwide. Prominent among these have been the stream-breeding frogs in the rainforests of eastern Australia. The amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd) has been postulated as the primary cause of these declines. We conducted a capture-mark-recapture study over a 7-year period on the endangered Fleay’s barred frog (Mixophyes fleayi) at two independent streams (30 km apart) in order to assess the stability of these populations. This species had undergone a severe decline across its narrow geographic range. Mark-recapture modelling showed that the number of individuals increased 3–10 fold along stream transects over this period. Frog detection probabilities were frequently above 50% but declined as the populations increased. Adult survival was important to overall population persistence in light of low recruitment events, suggesting that longevity may be a key factor in this recovery. One male and female were present in the capture record for >6 years. This study provides an unambiguous example of population recovery in the presence of Bd. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was the development, evaluation and analysis of a neuro-fuzzy classifier for a supervised and hard classification of coastal environmental vulnerability due to marine aquaculture using minimal training sets within a Geographic Information System (GIS). The neuro-fuzzy classification model NEFCLASS‐J, was used to develop learning algorithms to create the structure (rule base) and the parameters (fuzzy sets) of a fuzzy classifier from a set of labeled data. The training sites were manually classified based on four categories of coastal environmental vulnerability through meetings and interviews with experts having field experience and specific knowledge of the environmental problems investigated. The inter-class separability estimations were performed on the training data set to assess the difficulty of the class separation problem under investigation. The two training data sets did not follow the assumptions of multivariate normality. For this reason Bhattacharyy and Jeffries–Matusita distances were used to estimate the probability of correct classification. Further evaluation and analysis of the quality of the classification achieved low values of quantity and allocation disagreement and a good overall accuracy. For each of the four classes the user and producer values for accuracy were between 77% and 100%. In conclusion, the use of a neuro-fuzzy classifier for a supervised and hard classification of coastal environmental vulnerability demonstrated an ability to derive an accurate and reliable classification using a minimal number of training sets. [Copyright &y& Elsevier]

Aquaculture holds considerable potential to contribute to poverty alleviation, if it provides poor people with opportunities other than as primary producers. Integration of aquaculture into poverty reduction programmes provides means to diversify production systems and reduce food insecurity but also needs improved markets in locations where aquaculture can offer sustainable livelihoods to poor farming households. This study reviews the current constraints that poor people face in accessing markets in Cambodia and analyses its implications for pro-poor domestic aquaculture development. We use a Geographic Information System-based spatial Bayesian probability model to simulate market accessibility and estimate the numbers of poor people who could potentially benefit from improved market access under four different scenarios. Analysis of secondary data confirms that the potential for poor aquaculture producers to interact with urban markets in Cambodia is currently low. The potential of aquaculture to interact with rural markets is, however, high. It is concluded that the development of aquaculture has considerable potential to reduce the transaction costs in domestic fish trade by improved access of poor producers and consumers to rural markets in Cambodia. An aquaculture development strategy that improves rural market access could include benefits for up to 1 million poor aquatic resource users. [ABSTRACT FROM AUTHOR]

The tilapia fishery in a large Mexican reservoir has declined in recent years, promoting efforts to enhance stock quality in conjunction with feasibility studies for cage aquaculture. Spatial models to optimize cage location have been developed, incorporating aspects of topography, climate, hydrography, water quality and quantity, land use, infrastructure and socioeconomics. Three cage sizes were modelled, 5, 10 and 15 m diameter, for both high- and low-water levels. When full the, reservoir has a total area of 312 km but a reduction in water level of 13 m was recorded between wet and dry seasons, significantly reducing the surface area available for cages to 265 km. The results indicate a significant difference in the availability of sites between seasons. For the small, medium and large cages at high water level, the areas classified as highly suitable or suitable were 151, 184 and 146 km, respectively, while at low-water level these areas reduced to 113, 88 and 62 km. Modelling this change in water level and the subsequent loss of available sites provide qualitative and quantitative guidelines for the development of aquaculture sites, their seasonal management and future monitoring, outcomes that can only be achieved using Geographical Information Systems and associated technologies. [ABSTRACT FROM AUTHOR]

Aquaculture continues to be the fastest growing animal production industry and this rate of expansion must continue if aquaculture is to satisfy global demand for fish products in the face of dwindling capture fisheries. The relationship between aquaculture and biodiversity is complex, with examples of positive and negative impacts having been reported. To enable this expansion while avoiding negative impacts from introductions of exotic species, the investigation of indigenous species becomes important and worthwhile.This paper establishes the background to development of new species for culture and describes the example of the Mexican silverside Menidia estor, which has for centuries been the principal species in an artesanal fishery in Lake Pátzcuaro, Mexico. The species is geographically isolated and is unique but is now endangered because of a range of factors including overfishing, environmental degradation and introduction of exotic species. Considerable advances have been made recently in developing a closed reproductive cycle, understanding feeding and small-scale on-growing technology for the species. Based on this, a Darwin Initiative programme was developed focused on technology transfer to implement small-scale pilot on-growing thus helping to conserve the species and to improve livelihoods. This has allowed successful pilot scale development of aquaculture for the species while at the same time addressing the objectives of the international Convention on Biodiversity. [ABSTRACT FROM AUTHOR]

The Mexican silverside, Menidia estor, is a species with great regional importance and with very high prices in local markets. Unfortunately, due to high fisheries pressure, environmental degradation and pollution, the species has become endangered. Recently, there has been much progress in the biotechnology of this species, aimed at its culture, and the present paper describes the advances in feeding and nutrition of those important fish. M. estor is a stomachless, zooplantophagous fish, which also occasionally feeds on small fish and crustaceans in the adult stage. Studies on the digestive enzymatic activities show high proteolytic capacity and a late or different model of digestive maturation from that described for marine stomach fish. Nutritional studies on M. estor have shown that juveniles have dietary requirements of about 400 g kg−1 protein and 80 mg kg−1 vitamin C. The upper level of dietary carbohydrate for good growth and survival for juveniles is about 150 g kg−1. Based on the high docosahexaenoic acid (DHA) content in flesh when fed on diets low in DHA, it is believed that the species has the capacity to biosynthetize >20-carbon fatty acids from 18-carbon fatty acids. The high levels of DHA in flesh makes this fish a very significant potential component of human nutrition. Using these findings the first practical diets for commercial culture of the species have been developed. [ABSTRACT FROM AUTHOR]

The salinity tolerance of eggs, larvae, and juveniles of blacknose silverside Chirostoma promelas was investigated with the objective of optimizing hatchery practice. A high proportion (>90%) of eggs became eyed in all salinities. Eggs exposed to an instantaneous change of salinity hatched best at 0-15 practical salinity units (psu; 1 psu ≈ 1 0/00); reduced hatching occurred at 20 psu and no hatching occurred at 25-35 psu. By contrast, eggs exposed after 5 d to a slow change of salinity to freshwater over 48 h also hatched well at 0-15 psu, but they hatched at higher salinities as well. Fungal infections of eggs were greatest at 0 and 5 psu. Larvae exposed to an instantaneous change of salinity (0-25 psu) had the best survival rates at salinities of 0 psu (83%) and 5 psu (87%), but lower survival was obtained at 10 psu (49%) and 15 psu (22%) after 144 h. At 20 and 25 psu, larval mortality was 90% and 100%, respectively, after 48 h. In contrast, larvae exposed to a slow change of salinity over 48 b showed a higher salinity tolerance (43% survival at 20 psu), although higher salinities killed the fish. Juveniles had a high tolerance (100% survival) to a slow salinity change over 48 h at 0-25 psu. After 90 d, survival was best at 5-20 psu, optimal growth occurring at 5, 10, and 15 psu. Mortality was 100% in fish reared in freshwater after 75 d of cuhure, possibly a result of the high stress at this salinity. The osmolarity of muscle tissue of juveniles was not significantly different (P > 0.05) between trials, indicating efficient internal ionic regulation at all salinities. The wide salinity tolerance of blacknose silverside is clearly beneficial for its management and culture. [ABSTRACT FROM AUTHOR]