scholarly journals Methods to study organogenesis in decapod crustacean larvae. I. larval rearing, preparation, and fixation

2021 ◽  
Vol 75 (1) ◽  
Author(s):  
G. Torres ◽  
R. R. Melzer ◽  
F. Spitzner ◽  
Z. Šargač ◽  
S. Harzsch ◽  
...  
Keyword(s):  
Decapod Crustacean ◽  
Companion Paper ◽  
Larval Survival ◽  
Complex Life Cycle ◽  
Environmental Drivers ◽  
Niche Shift ◽  
Larval Rearing ◽  
Evolutionary Potential ◽  
Pelagic Larvae ◽  
Organ Systems

AbstractCrustacean larvae have served as distinguished models in the field of Ecological Developmental Biology (“EcoDevo”) for many decades, a discipline that examines how developmental mechanisms and their resulting phenotype depend on the environmental context. A contemporary line of research in EcoDevo aims at gaining insights into the immediate tolerance of organisms and their evolutionary potential to adapt to the changing abiotic and biotic environmental conditions created by anthropogenic climate change. Thus, an EcoDevo perspective may be critical to understand and predict the future of organisms in a changing world. Many decapod crustaceans display a complex life cycle that includes pelagic larvae and, in many subgroups, benthic juvenile–adult stages so that a niche shift occurs during the transition from the larval to the juvenile phase. Already at hatching, the larvae possess a wealth of organ systems, many of which also characterise the adult animals, necessary for autonomously surviving and developing in the plankton and suited to respond adaptively to fluctuations of environmental drivers. They also display a rich behavioural repertoire that allows for responses to environmental key factors such as light, hydrostatic pressure, tidal currents, and temperature. Cells, tissues, and organs are at the basis of larval survival, and as the larvae develop, their organs continue to grow in size and complexity. To study organ development, researchers need a suite of state-of-the-art methods adapted to the usually very small size of the larvae. This review and the companion paper set out to provide an overview of methods to study organogenesis in decapod larvae. This first section focuses on larval rearing, preparation, and fixation, whereas the second describes methods to study cells, tissues, and organs.

scholarly journals Methods to study organogenesis in decapod crustacean larvae II: analysing cells and tissues

2021 ◽  
Vol 75 (1) ◽  
Author(s):  
R. R. Melzer ◽  
F. Spitzner ◽  
Z. Šargač ◽  
M. K. Hörnig ◽  
J. Krieger ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Imaging Techniques ◽  
Light And Electron Microscopy ◽  
Decapod Crustacean ◽  
Companion Paper ◽  
Future Directions ◽  
Reflected Light ◽  
Organ Systems ◽  
Adult Organism

AbstractCells and tissues form the bewildering diversity of crustacean larval organ systems which are necessary for these organisms to autonomously survive in the plankton. For the developmental biologist, decapod crustaceans provide the fascinating opportunity to analyse how the adult organism unfolds from organ Anlagen compressed into a miniature larva in the sub-millimetre range. This publication is the second part of our survey of methods to study organogenesis in decapod crustacean larvae. In a companion paper, we have already described the techniques for culturing larvae in the laboratory and dissecting and chemically fixing their tissues for histological analyses. Here, we review various classical and more modern imaging techniques suitable for analyses of eidonomy, anatomy, and morphogenetic changes within decapod larval development, and protocols including many tips and tricks for successful research are provided. The methods cover reflected-light-based methods, autofluorescence-based imaging, scanning electron microscopy, usage of specific fluorescence markers, classical histology (paraffin, semithin and ultrathin sectioning combined with light and electron microscopy), X-ray microscopy (µCT), immunohistochemistry and usage of in vivo markers. For each method, we report our personal experience and give estimations of the method’s research possibilities, the effort needed, costs and provide an outlook for future directions of research.

scholarly journals Multi-model seascape genomics identifies distinct environmental drivers of selection among sympatric marine species

2020 ◽  
Author(s):  
Erica Nielsen ◽  
Romina Henriques ◽  
Maria Beger ◽  
Robert Toonen ◽  
Sophie von der Heyden
Keyword(s):  
Global Change ◽  
Outlier Detection ◽  
Genomic Variation ◽  
Sea Surface ◽  
Environmental Drivers ◽  
Comparative Approach ◽  
Evolutionary Potential ◽  
Environmental Selection ◽  
Outlier Loci ◽  
Isolation By Environment

Abstract Background: As global change and anthropogenic pressures continue to increase, conservation and management increasingly needs to consider species’ potential to adapt to novel environmental conditions. Therefore, it is imperative to characterise the main selective forces acting on ecosystems, and how these may influence the evolutionary potential of populations and species. Using a multi-model seascape genomics approach, we compare putative environmental drivers of selection in three sympatric southern African marine invertebrates with contrasting ecology and life histories: Cape urchin (Parechinus angulosus), Common shore crab (Cyclograpsus punctatus), and Granular limpet (Scutellastra granularis). Results: Using pooled (Pool-seq), restriction-site associated DNA sequencing (RAD-seq), and seven outlier detection methods, we characterise genomic variation between populations along a strong biogeographical gradient. Of the three species, only S. granularis showed significant isolation-by-distance, and isolation-by-environment driven by sea surface temperatures (SST). In contrast, sea surface salinity (SSS) and range in air temperature correlated more strongly with genomic variation in C. punctatus and P. angulosus. Differences were also found in genomic structuring between the three species, with outlier loci contributing to two clusters in the East and West Coasts for S. granularis and P. angulosus, but not for C. punctatus. Conclusion: The findings illustrate distinct evolutionary potential across species, suggesting that species-specific habitat requirements and responses to environmental stresses may be better predictors of evolutionary patterns than the strong environmental gradients within the region. We also found large discrepancies between outlier detection methodologies, and thus offer a novel multi-model approach to identifying the principal environmental selection forces acting on species. Overall, this work highlights how adding a comparative approach to seascape genomics (both with multiple models and species) can elucidate the intricate evolutionary responses of ecosystems to global change.

scholarly journals Multi-model seascape genomics identifies distinct environmental drivers of selection among sympatric marine species

2020 ◽  
Author(s):  
Erica Nielsen ◽  
Romina Henriques ◽  
Maria Beger ◽  
Robert Toonen ◽  
Sophie von der Heyden
Keyword(s):  
Global Change ◽  
Outlier Detection ◽  
Genomic Variation ◽  
Sea Surface ◽  
Environmental Drivers ◽  
Comparative Approach ◽  
Evolutionary Potential ◽  
Environmental Selection ◽  
Outlier Loci ◽  
Isolation By Environment

Abstract Background: As global change and anthropogenic pressures continue to increase, conservation and management increasingly needs to consider species’ potential to adapt to novel environmental conditions. Therefore, it is imperative to characterise the main selective forces acting on ecosystems, and how these may influence the evolutionary potential of populations and species. Using a multi-model seascape genomics approach, we compare the dominant environmental drivers of selection in three sympatric southern African marine invertebrates with contrasting ecology and life histories: Cape urchin ( Parechinus angulosus ), Common shore crab ( Cyclograpsus punctatu s), and Granular limpet ( Scutellastra granularis ). Results: Using pooled (Pool-seq), restriction-site associated DNA sequencing (RAD-seq), and seven outlier detection methods, we characterise genomic variation between populations along a strong biogeographical gradient. Of the three species, only S. granularis showed significant isolation-by-distance, and isolation-by-environment driven by sea surface temperatures (SST). In contrast, sea surface salinity (SSS) and range in air temperature correlated more strongly with genomic variation in C. punctatus and P. angulosus . Differences were also found in genomic structuring between the three species, with outlier loci contributing to two clusters in the East and West Coasts for S. granularis and P. angulosus , but not for C. punctatus . Conclusion: The findings illustrate distinct evolutionary potential across species, suggesting that species-specific habitat requirements and responses to environmental stresses better predict evolutionary patterns than the strong environmental gradients within the region. We also found large discrepancies between outlier detection methodologies, and thus offer a novel multi-model approach to identifying the principal environmental selection forces acting on species. Overall, this work highlights how adding a comparative approach to seascape genomics (both with multiple models and species) can elucidate the intricate evolutionary responses of ecosystems to global change.

Aquaculture Revisited

1976 ◽  
Vol 33 (4) ◽  
pp. 880-887 ◽  
Author(s):  
John E. Bardach
Keyword(s):  
Social Impact ◽  
Information Dissemination ◽  
Raw Materials ◽  
Survival Rates ◽  
Larval Survival ◽  
Larval Rearing ◽  
Tropical Asia ◽  
Economy Of Scale ◽  
The Pacific ◽  
Choice Of Species

Opportunities for and constraints of animal aquaculture are considered with special reference to the Pacific basin. Choice of species for husbandry depends on biological, cultural, and marketability criteria. Seed production (spawning and larval rearing) may be centralized, with certain economy of scale advantages, even in artisanal aquaculture enterprises, provided adequate distribution facilities for postlarvae are made. Larval survival rates for several actual or potential cultivars still need enhancement through applied research. Practices for the growout phase of aquatic stock differ, depending on the intensity of fixed and variable inputs, by analogy with terrestrial systems one may distinguish feedlot, managed pasturage, and ranching modes. For much of tropical Asia best expansion opportunities exist in managed pasturage polyculture possibly combining the grow-out of crustacea for export with local, largely herbivorous and planktivorous semistaple species. Extraneously supplied feeds, when used, will differ with the species and locally available raw materials. Nonbiotechnical constraints to aquaculture expansion are found in the areas of training, credit, extension, social impact of change, and information dissemination. They may be as difficult, if not more difficult, to overcome as purely biological ones.

Occurrence of nematode parasites in Calocaris macandreae (Crustacea: Decapoda) from an Irish Sea population

1986 ◽  
Vol 66 (2) ◽  
pp. 293-301 ◽  
Author(s):  
J. A. Perez-Calderon
Keyword(s):  
Life Cycle ◽  
Gadus Morhua ◽  
Barents Sea ◽  
Decapod Crustacean ◽  
Host Cells ◽  
Complex Life Cycle ◽  
Irish Sea ◽  
Shore Crab ◽  
Melanogrammus Aeglefinus ◽  
Decapod Crustaceans

INTRODUCTIONA number of nematodes are known to develop in decapod crustaceans. These parasite nematodes are present in the coelom of the host either free or surrounded by different types of host cells. All belong to the order Ascaridida or Spirurida and most of them develop only to the third larval stage in the decapod host; further development takes place in a predator of the crustacean which is generally a teleost or elasmobranch (Berland, 1961; Ouspenskaia, 1960; Petter, 1970; Poinar & Kuris, 1975;Uspenskaja, 1953; Yamaguti, 1961). The life-cycle in most cases is not fully understood. Ouspenskaia (1960) and Uspenskaja (1953, 1963) deduced the life-cycle for Ascarophis morrhuae van Beneden and A. filiformis Poljanski in the Barents Sea by relating the larvae found in decapod crustaceans through affinity of characters to the adults present in cod (Gadus morhua L.) and haddock (Melanogrammus aeglefinus L.). Similarly, the life-cycle of the spirurid Proleptus obtusus was described by Lloyd (1928); the larvae occur in a decapod crustacean, usually the hermit crab Pagurus bernhardus L. and in some cases the shore crab Carcinus maenas L. and the adults are found in the lesser spotted dogfish (Scyliorhinus canicula L.). A more complex life-cycle has been proposed for some anisakids such as Anisakis, Contracaecum and Hysterothylacium (Berland, 1961; Norris & Overstreet, 1976; Wootten, 1978) in which more than one intermediate host is required.

Pelagic habitat and offspring survival in the eastern stock of Atlantic bluefin tuna

2018 ◽  
Vol 76 (2) ◽  
pp. 549-558 ◽  
Author(s):  
Patricia Reglero ◽  
Rosa Balbín ◽  
Franciso Javier Abascal ◽  
Antonio Medina ◽  
Diego Alvarez-Berastegui ◽  
...  
Keyword(s):  
Full Range ◽  
Survival Function ◽  
Bluefin Tuna ◽  
Larval Survival ◽  
Temperature Data ◽  
Biological Model ◽  
Sampling Effort ◽  
Larval Rearing ◽  
Atlantic Bluefin Tuna ◽  
Survival Index

Abstract In this manuscript, we test how an understanding of geographical variation in larval fitness in relation to temperature and habitat use could be a useful method to improve our understanding of recruitment and develop better indices of annual recruitment. On the basis of the assumption that growth and survival of tuna larvae are influenced by temperature, we have developed a potential larval survival index for Atlantic bluefin tuna (Thunnus thynnus) by combining empirical data from egg and larval rearing experiments with temperature data from hydrodynamic models. The experiments were designed to test the full range of temperature variability that bluefin larvae would experience in the field and provide a mechanistic understanding of the processes driving egg and larval survival. We then developed a biological model using the temperature-related growth expressions and a size-dependent survival function for the larvae. The biological model was applied to a time-series of spatially explicit temperature data for the western Mediterranean from the Strait of Gibraltar to 6°E, which includes the major recognized bluefin tuna eastern stock spawning area, the Balearic Sea. Our results show that areas with high probabilities of larval survival coincide with those that would be considered as optimal based on other data sources (ichthyoplankton surveys, spawning female locations from commercial fisheries data, and adult tracking data). However, evidence of spawning has been found in areas with suboptimal thermal habitats, as predicted by the model, which we discuss regarding sampling effort and salinity fronts. There was a good match between the survival index and recruitment indices from standardized CPUE fisheries data. These results have implications for our understanding of the recruitment process of the eastern stock of Atlantic bluefin tuna, since they suggest that the combined effects of temporal and spatial variability of the environment drive recruitment success, which has important implications for the management of the species.

scholarly journals Coral larvae for restoration and research: a large-scale method for rearing Acropora millepora larvae, inducing settlement, and establishing symbiosis

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3732 ◽  
Author(s):  
F. Joseph Pollock ◽  
Sefano M. Katz ◽  
Jeroen A.J.M. van de Water ◽  
Sarah W. Davies ◽  
Margaux Hein ◽  
...  
Keyword(s):  
Large Scale ◽  
Larval Settlement ◽  
Larval Survival ◽  
Coralline Algae ◽  
Larval Rearing ◽  
Crustose Coralline Algae ◽  
Minimal Impact ◽  
Acropora Millepora ◽  
Wide Range ◽  
Order Of Magnitude

Here we describe an efficient and effective technique for rearing sexually-derived coral propagules from spawning through larval settlement and symbiont uptake with minimal impact on natural coral populations. We sought to maximize larval survival while minimizing expense and daily husbandry maintenance by experimentally determining optimized conditions and protocols for gamete fertilization, larval cultivation, induction of larval settlement by crustose coralline algae, and inoculation of newly settled juveniles with their dinoflagellate symbiont Symbiodinium. Larval rearing densities at or below 0.2 larvae mL−1 were found to maximize larval survival and settlement success in culture tanks while minimizing maintenance effort. Induction of larval settlement via the addition of a ground mixture of diverse crustose coralline algae (CCA) is recommended, given the challenging nature of in situ CCA identification and our finding that non settlement-inducing CCA assemblages do not inhibit larval settlement if suitable assemblages are present. Although order of magnitude differences in infectivity were found between common Great Barrier Reef Symbiodinium clades C and D, no significant differences in Symbiodinium uptake were observed between laboratory-cultured and wild-harvested symbionts in each case. The technique presented here for Acropora millepora can be adapted for research and restoration efforts in a wide range of broadcast spawning coral species.

scholarly journals A fine-scale multi-step approach to understand fish recruitment variability

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Pablo Brosset ◽  
Andrew Douglas Smith ◽  
Stéphane Plourde ◽  
Martin Castonguay ◽  
Caroline Lehoux ◽  
...  
Keyword(s):  
Egg Production ◽  
Adult Population ◽  
Synergetic Effect ◽  
Fish Population ◽  
Larval Survival ◽  
Population Characteristics ◽  
Environmental Drivers ◽  
Fine Scale ◽  
Atlantic Mackerel ◽  
Spatio Temporal

Abstract Recruitment is one of the dominant processes regulating fish population productivity. It is, however, notoriously difficult to predict, as it is the result of a complex multi-step process. Various fine-scale drivers might act on the pathway from adult population characteristics to spawning behaviour and egg production, and then to recruitment. Here, we provide a holistic analysis of the Northwest Atlantic mackerel recruitment process from 1982 to 2017 and exemplify why broad-scale recruitment–environment relationships could become unstable over time. Various demographic and environmental drivers had a synergetic effect on recruitment, but larval survival through a spatio-temporal match with prey was shown to be the key process. Recruitment was also mediated by maternal effects and a parent–offspring fitness trade-off due to the different feeding regimes of adults and larvae. A mismatch curtails the effects of high larval prey densities, so that despite the abundance of food in recent years, recruitment was relatively low and the pre-existing relationship with overall prey abundance broke down. Our results reaffirm major recruitment hypotheses and demonstrate the importance of fine-scale processes along the recruitment pathway, helping to improve recruitment predictions and potentially fisheries management.

Evolution, Microbes, and Changing Ocean Conditions

2020 ◽  
Vol 12 (1) ◽  
pp. 181-208 ◽  
Author(s):  
Sinéad Collins ◽  
Philip W. Boyd ◽  
Martina A. Doblin
Keyword(s):  
Experimental Evolution ◽  
Environmental Variability ◽  
Cumulative Effect ◽  
Model Systems ◽  
Environmental Drivers ◽  
Marine Microbes ◽  
Evolutionary Potential ◽  
Tolerance Limits ◽  
Different Types

Experimental evolution and the associated theory are underutilized in marine microbial studies; the two fields have developed largely in isolation. Here, we review evolutionary tools for addressing four key areas of ocean global change biology: linking plastic and evolutionary trait changes, the contribution of environmental variability to determining trait values, the role of multiple environmental drivers in trait change, and the fate of populations near their tolerance limits. Wherever possible, we highlight which data from marine studies could use evolutionary approaches and where marine model systems can advance our understanding of evolution. Finally, we discuss the emerging field of marine microbial experimental evolution. We propose a framework linking changes in environmental quality (defined as the cumulative effect on population growth rate) with population traits affecting evolutionary potential, in order to understand which evolutionary processes are likely to be most important across a range of locations for different types of marine microbes.

Layered effects of parental condition and larval survival on the recruitment of neighboring haddock stocks

2015 ◽  
Vol 72 (11) ◽  
pp. 1672-1681 ◽  
Author(s):  
Kevin D. Friedland ◽  
Robert T. Leaf ◽  
Trond Kristiansen ◽  
Scott I. Large
Keyword(s):  
Gulf Of Maine ◽  
Full Range ◽  
Larval Survival ◽  
Calanus Finmarchicus ◽  
Environmental Drivers ◽  
Melanogrammus Aeglefinus ◽  
Concentration Data ◽  
Bank Stock ◽  
Parental Condition ◽  
Recruitment Variability

We used remote sensing chlorophyll a concentration data, spring copepod abundance, and individual fish condition information to understand the annual recruitment variability of two neighboring haddock (Melanogrammus aeglefinus) stocks in the Gulf of Maine region. When we considered the full range of recruitment variability, the abundance of the copepods Calanus finmarchicus and Pseudocalanus spp. failed to explain the variation in survivor ratio in either stock. However, when we examined this relationship with subsets of the data, we found that Pseudocalanus spp. appears to have had an effect on survivor ratio. The full range of recruitment variability of the Georges Bank stock was found to correlate with the timing and size of the fall bloom the year before recruitment, which has been termed the parental condition hypothesis, suggesting that the fall bloom affects the condition of spawning adults and thus recruitment. The absence of a correlation between fall bloom and recruitment in the Gulf of Maine stock can be attributed to the difference in fall bloom frequency between the two stock areas. It appears that both parental condition and larval survival affect haddock recruitment; however, the relative impact of these effects depends on the contrasting nature of ecosystem environmental drivers.

Sign in / Sign up

Export Citation Format

Share Document