scholarly journals A review of the biology and genetics of sea lice

2006 ◽  
Vol 63 (7) ◽  
pp. 1304-1316 ◽  
Author(s):  
Karin Boxaspen
Keyword(s):  
Population Structure ◽  
North Atlantic ◽  
Developmental Stages ◽  
Management Strategies ◽  
Molecular Techniques ◽  
Sea Lice ◽  
Lepeophtheirus Salmonis ◽  
New Research ◽  
And Control

Abstract Studies of the biology of sea lice have been conducted from various perspectives for two decades. For Lepeophtheirus spp., most of the published literature has centred on the economically important Lepeophtheirus salmonis, while for Caligus spp., research has focused on a wider range of species. The most numerous species of Caligus in North Atlantic waters, however, is Caligus elongatus, which is also economically important to salmon farming. Since the last review by Pike, A. W., and Wadsworth, S. L. (1999. Sea lice on salmonids: their biology and control. Advances in Parasitology, 44: 234–337.), research on sea lice has developed considerably, including the application of genetic methods. This new research has focused on life history biology, studying developmental stages under different environmental conditions (e.g. temperature and salinity), behaviour, distribution and the dispersal of free-living stages, monitoring practices, population structure, and modelling. The results of this research have informed risk analyses and allowed the refinement of management strategies to reduce sea lice infestations in wild and farmed populations of anadromous salmonids. Molecular techniques have been used to describe population structure and identify differences in genetic characterization of geographically separate populations and population markers. Research has been initiated to understand the parasite–host relationship at a molecular level and to develop a vaccine against sea lice.

Applications of Biotechnology for Characterization of Plants and Pests as the Key Components of Plant Protection and Production Strategies: A Review

2020 ◽  
Vol 8 (3) ◽  
pp. 247-288
Author(s):  
Melaku Alemu
Keyword(s):  
Genome Mapping ◽  
Plant Protection ◽  
Abiotic Factors ◽  
Plant Genetic Resources ◽  
Management Strategies ◽  
Molecular Techniques ◽  
Successful Implementation ◽  
Global Food Security ◽  
Production Strategies

The second Sustainable Developmental Goals (SDG), among the seventeen SDG, is concerned with the pursuit of global food security and agricultural sustainability, which become the key to the success of the entire SDG. Whereas agricultural production and productivity are heavily threatened by the incidence of pests that inflict huge losses in various forms. This calls for prompt applications of biotechnology for the fast, accurate and reliable means for characterization of plant generic resources and pests as it is the pre-requisite and gateway for designing appropriate plant protection and production strategies. It is imperative that pests be identified properly so that judicious use of the literature can be made and sustainable management strategies can be implemented at the right stage. To this end, the application of biotechnology has made significant advances for reliable characterization of plant genetic resources as well as accurate diagnosis of pests, study of their genetic diversity and variability, detailed mechanisms of their transmission and evolutionary relationships. Accordingly, this review article covers the comprehensive account of the various molecular techniques, genome mapping and OMICS sciences utilized for characterization plants and pests that ultimately allow the detailed study of the biology and epidemiology of pests at any stage of their life cycle. The resulting data are eventually employed for enhancing successful implementation of sustainable plant protection and production strategies. In conclusion, the increasing projections of transboundary pests, environmental and abiotic factors together with the continuous scientific advancements and breakthroughs have made biotechnology to be an important engine of bioeconomy for generating invaluable products, processes and services. Int. J. Appl. Sci. Biotechnol. Vol 8(3): 247-288

scholarly journals Characterization of Dendrolimus houi Lajonquiere (Lepidoptera: Lasiocampidae) Transcriptome across All Life Stages

Insects ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 442 ◽  
Author(s):  
Xiaohong Han ◽  
Ciding Lu ◽  
Scott M. Geib ◽  
Junxian Zheng ◽  
Songqing Wu ◽  
...  
Keyword(s):  
Yunnan Province ◽  
High Throughput Sequencing ◽  
Developmental Stages ◽  
Management Strategies ◽  
Life Stages ◽  
Transcriptome Data ◽  
Climatic Extremes ◽  
Two Generations ◽  
Coniferous Tree Species

Dendrolimus houi Lajonquiere is a phytophagous caterpillar infesting many economically important coniferous tree species in China, causing serious economic and ecological environment losses. Based on previous research, it has one generation per year in South China and East China in contrast to two generations per year in Yunnan province in southwestern China. The species is potentially resilient to climatic extremes in these regions with the eggs and 1st instar larvae surviving in the winter (5 °C), older instar larvae and pupae surviving high temperatures in the summer (35 °C), suggesting some temperature stress tolerance during different developmental stages. However, little is known in this species at the genetic and genomic level. In this study, we used high throughput sequencing to obtain transcriptome data from different developmental stages (eggs, 1st–3rd instar larvae, 4th–5th instar larvae, 6th–7th instar larvae, pupae, male and female adults), which were collected from Fujian province. In total, we obtained approximately 90 Gb of data, from which 33,720 unigenes were assembled and 17,797 unigenes were annotated. We furtherly analyzed the differentially expressed genes (DGEs) across all stages, the largest number between the eggs and 1st instar larvae stage and gene expression varied significantly in different developmental stages. Furthermore, 4138 SSR genes and 114,977 SNP loci were screened from transcriptome data. This paper will be a foundation for further study towards improved integrated pest management strategies for this species.

scholarly journals A machine vision system for tracking population behavior of zooplankton in small-scale experiments: a case study on salmon lice (Lepeophtheirus salmonis Krøyer, 1838) copepodite population responses to different light stimuli

Biology Open ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. bio050724
Author(s):  
Bjarne Kvæstad ◽  
Trond Nordtug ◽  
Andreas Hagemann
Keyword(s):  
Machine Vision ◽  
Developmental Stages ◽  
Vision System ◽  
Behavioral Responses ◽  
Experimental System ◽  
Sea Lice ◽  
Small Scale ◽  
Lepeophtheirus Salmonis ◽  
Salmon Lice ◽  
Light Stimuli

ABSTRACTTo achieve efficient and preventive measures against salmon lice (Lepeophtheirus salmonis Krøyer, 1838) infestation, a better understanding of behavioral patterns of the planktonic life stages is key. To investigate light responses in L. salmonis copepodites, a non-intrusive experimental system was designed to measure behavioral responses in a 12.5-l volume using machine vision technology and methodology. The experimental system successfully tracked the collective movement patterns of the sea lice population during exposure to different light stimuli emitted from alternating zones in the system. This system could further be used to study behavioral responses to different physical cues of various developmental stages of sea lice or other zooplankton.

Assessment of stable isotopic signatures as a means to track the exchange of sea lice (Lepeophtheirus salmonis) between host fish populations

2011 ◽  
Vol 68 (7) ◽  
pp. 1243-1251 ◽  
Author(s):  
Susan Dean ◽  
Claudio DiBacco ◽  
Robert Scott McKinley
Keyword(s):  
First Generation ◽  
Developmental Stages ◽  
Fish Population ◽  
Fish Populations ◽  
Sea Lice ◽  
Lepeophtheirus Salmonis ◽  
Host Fish ◽  
Isotopic Signatures ◽  
Stable Isotopic ◽  
Over Time

The viability of stable isotopic carbon (δ13C) and nitrogen (δ15N) signatures to track the exchange of sea lice, Lepeophtheirus salmonis , between hosts was tested. It was predicted that nonfeeding sea lice would experience lowered δ13C signatures and enriched δ15N signatures owing, at least in part, to moulting during development. It was also predicted that newly settled parasitic first generation sea lice (late stage copepodids) would retain isotopic signatures indistinguishable from their natal host fish population. During this laboratory study, δ13C signatures of nonfeeding sea lice developmental stages declined over time, while the δ13C signature of chalimus III sea lice was not significantly different from fin and gill signatures of their natal hosts, thus providing an isotopic link to their natal host fish population. In contrast, δ15N analysis did not show promise as a tracer in this study, as host fish populations did not display distinct δ15N signatures. These results suggest that δ13C signatures may be applied to identify sources of sea lice epizootics and potentially quantify the exchange of sea lice between cultured and wild salmon populations.

Introduction

2018 ◽  
Author(s):  
Elizabeth S. Radcliffe
Keyword(s):  
Early Modern ◽  
Historical Background ◽  
Consistent Picture ◽  
And Control ◽  
Good And Evil

The Introduction offers, first, a brief historical background to Hume’s theory of the passions, which is further elaborated in the APPENDIX. Foremost among the theses of the early modern rationalists—like Reynolds, Senault, Descartes, Cudworth, and Clarke—to which Hume is responding are: that many passions left unregulated lead to the pursuit of unsuitable objects, that reason can overcome the pernicious influence of the passions and control our actions, and that the passions are states that represent good and evil. Second, the Introduction presents a sketch of Hume’s characterization of reason and passion and his account of their relationship. Third, it explains the method of interpretation used in this book and previews its chapters. The approach is coherentist: to present an intelligible and consistent picture of Hume’s theory of passion and action, accounting for as many of the relevant texts as possible.

scholarly journals Design, Construction, and Control for an Underwater Vehicle Type Sepiida

Robotica ◽  
2020 ◽  
pp. 1-18
Author(s):  
M. Garcia ◽  
P. Castillo ◽  
E. Campos ◽  
R. Lozano
Keyword(s):  
Embedded System ◽  
Closed Loop ◽  
Underwater Vehicle ◽  
Mathematical Representation ◽  
Closed Loop System ◽  
Vehicle Type ◽  
Mathematical Equations ◽  
And Control ◽  
Design Construction

SUMMARY A novel underwater vehicle configuration with an operating principle as the Sepiida animal is presented and developed in this paper. The mathematical equations describing the movements of the vehicle are obtained using the Newton–Euler approach. An analysis of the dynamic model is done for control purposes. A prototype and its embedded system are developed for validating analytically and experimentally the proposed mathematical representation. A real-time characterization of one mass is done to relate the pitch angle with the radio of displacement of the mass. In addition, first validation of the closed-loop system is done using a linear controller.

scholarly journals Contributions to Management Strategies in the NE Atlantic Regarding the Life History and Population Structure of a Key Deep-Sea Fish (Mora moro)

Biology ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 522
Author(s):  
Régis Santos ◽  
Wendell Medeiros-Leal ◽  
Osman Crespo ◽  
Ana Novoa-Pabon ◽  
Mário Pinho
Keyword(s):  
Population Structure ◽  
Life History ◽  
Deep Sea ◽  
Management Strategies ◽  
Size Composition ◽  
Large Size ◽  
The Common ◽  
Fishing Impacts ◽  
Sea Fish

With the commercial fishery expansion to deeper waters, some vulnerable deep-sea species have been increasingly captured. To reduce the fishing impacts on these species, exploitation and management must be based on detailed and precise information about their biology. The common mora Mora moro has become the main deep-sea species caught by longliners in the Northeast Atlantic at depths between 600 and 1200 m. In the Azores, landings have more than doubled from the early 2000s to recent years. Despite its growing importance, its life history and population structure are poorly understood, and the current stock status has not been assessed. To better determine its distribution, biology, and long-term changes in abundance and size composition, this study analyzed a fishery-dependent and survey time series from the Azores. M. moro was found on mud and rock bottoms at depths below 300 m. A larger–deeper trend was observed, and females were larger and more abundant than males. The reproductive season took place from August to February. Abundance indices and mean sizes in the catch were marked by changes in fishing fleet operational behavior. M. moro is considered vulnerable to overfishing because it exhibits a long life span, a large size, slow growth, and a low natural mortality.

scholarly journals Clinical characterization of dysautonomia in long COVID-19 patients

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nicolas Barizien ◽  
Morgan Le Guen ◽  
Stéphanie Russel ◽  
Pauline Touche ◽  
Florent Huang ◽  
...  
Keyword(s):  
Mixed Models ◽  
Repeated Measures ◽  
Physical Medicine ◽  
Persistent Symptoms ◽  
Index Changes ◽  
Changes Over Time ◽  
And Control ◽  
Testing Group ◽  
Over Time

AbstractIncreasing numbers of COVID-19 patients, continue to experience symptoms months after recovering from mild cases of COVID-19. Amongst these symptoms, several are related to neurological manifestations, including fatigue, anosmia, hypogeusia, headaches and hypoxia. However, the involvement of the autonomic nervous system, expressed by a dysautonomia, which can aggregate all these neurological symptoms has not been prominently reported. Here, we hypothesize that dysautonomia, could occur in secondary COVID-19 infection, also referred to as “long COVID” infection. 39 participants were included from December 2020 to January 2021 for assessment by the Department of physical medicine to enhance their physical capabilities: 12 participants with COVID-19 diagnosis and fatigue, 15 participants with COVID-19 diagnosis without fatigue and 12 control participants without COVID-19 diagnosis and without fatigue. Heart rate variability (HRV) during a change in position is commonly measured to diagnose autonomic dysregulation. In this cohort, to reflect HRV, parasympathetic/sympathetic balance was estimated using the NOL index, a multiparameter artificial intelligence-driven index calculated from extracted physiological signals by the PMD-200 pain monitoring system. Repeated-measures mixed-models testing group effect were performed to analyze NOL index changes over time between groups. A significant NOL index dissociation over time between long COVID-19 participants with fatigue and control participants was observed (p = 0.046). A trend towards significant NOL index dissociation over time was observed between long COVID-19 participants without fatigue and control participants (p = 0.109). No difference over time was observed between the two groups of long COVID-19 participants (p = 0.904). Long COVID-19 participants with fatigue may exhibit a dysautonomia characterized by dysregulation of the HRV, that is reflected by the NOL index measurements, compared to control participants. Dysautonomia may explain the persistent symptoms observed in long COVID-19 patients, such as fatigue and hypoxia. Trial registration: The study was approved by the Foch IRB: IRB00012437 (Approval Number: 20-12-02) on December 16, 2020.

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