scholarly journals The prevalence of Aphanomyces astaci in invasive signal crayfish from the UK and implications for native crayfish conservation

Parasitology ◽  
2017 ◽  
Vol 144 (4) ◽  
pp. 411-418 ◽  
Author(s):  
J. JAMES ◽  
S. NUTBEAM-TUFFS ◽  
J. CABLE ◽  
A. MRUGAŁA ◽  
N. VIÑUELA-RODRIGUEZ ◽  
...  
Keyword(s):  
Average Rate ◽  
Signal Crayfish ◽  
Aphanomyces Astaci ◽  
Virulent Strains ◽  
Pathogen Prevalence ◽  
Crayfish Population ◽  
To Come ◽  
Group B ◽  
The Uk ◽  
Native Crayfish

SUMMARYThe crayfish plague agent, Aphanomyces astaci, has spread throughout Europe, causing a significant decline in native European crayfish. The introduction and dissemination of this pathogen is attributed to the spread of invasive North American crayfish, which can act as carriers for A. astaci. As native European crayfish often succumb to infection with A. astaci, determining the prevalence of this pathogen in non-native crayfish is vital to prioritize native crayfish populations for managed translocation. In the current study, 23 populations of invasive signal crayfish (Pacifastacus leniusculus) from the UK were tested for A. astaci presence using quantitative PCR. Altogether, 13 out of 23 (56·5%) populations were found to be infected, and pathogen prevalence within infected sites varied from 3 to 80%. Microsatellite pathogen genotyping revealed that at least one UK signal crayfish population was infected with the A. astaci genotype group B, known to include virulent strains. Based on recent crayfish distribution records and the average rate of signal crayfish population dispersal, we identified one native white-clawed crayfish (Austropotamobius pallipes) population predicted to come into contact with infected signal crayfish within 5 years. This population should be considered as a priority for translocation.

Relaxed attitude towards spreading of alien crayfish species affects protection of native crayfish species: case studies and lessons learnt from a Fennoscandian viewpoint

2020 ◽  
Vol 25 (1) ◽  
pp. 39-46
Author(s):  
Japo Jussila ◽  
Lennart Edsman
Keyword(s):  
Competitive Advantage ◽  
Pacifastacus Leniusculus ◽  
Astacus Astacus ◽  
Signal Crayfish ◽  
Aphanomyces Astaci ◽  
Noble Crayfish ◽  
Native Crayfish ◽  
Chronic Carrier ◽  
Highly Virulent ◽  
Crayfish Species

Abstract The spreading of the alien signal crayfish (Pacifastacus leniusculus) is posing an ongoing threat to native European crayfish species in Fennoscandia, like the native noble crayfish (Astacus astacus). The signal crayfish is commonly a chronic carrier of the crayfish plague (Aphanomyces astaci), thus, in addition to being more competitive than noble crayfish, it also has a competitive advantage in this disease over the noble crayfish. The challenges rising from the introduction of the alien signal crayfish to Sweden, Finland and finally also Norway, are similar in nature. The licensed and unlicensed spreading of this species also has a similar history in these countries. In this paper we describe some of the patters of the spread of alien signal crayfish and highlight the detrimental nature of an alien crayfish, accompanied by a highly virulent disease, to native Fennoscandian crayfish and also to native Fennoscandian ecosystems. A halt to the further spreading of alien signal crayfish in Fennoscandia is the only means to ensure successful conservation outcomes for the noble crayfish.

scholarly journals Chronic crayfish plague infection and eroded swimmeret syndrome in Lake Saimaa (Finland) signal crayfish

2017 ◽  
Vol 23 (1) ◽  
pp. 23-28
Author(s):  
Japo Jussila ◽  
Vese Tiitinen ◽  
Lennart Edsman
Keyword(s):  
Chronic Infection ◽  
Reproductive Output ◽  
Catch Per Unit Effort ◽  
Egg Hatching ◽  
Signal Crayfish ◽  
Aphanomyces Astaci ◽  
Unit Effort ◽  
History Of ◽  
Crayfish Population ◽  
Lake Saimaa

Abstract We present data and results from a 9-year survey (2009 – 2017) of the Lake Saimaa signal crayfish population in Finland. This population has a history of chronic infection with Aphanomyces astaci. It has now been discovered that female signal crayfish from Lake Saimaa suffer from various stages of eroded swimmeret syndrome (ESS), and male crayfish also show symptoms of ESS-like trauma (i.e., eroded swimmerets and gonopods). Our data demonstrates the prevalence of A. astaci infection, with gross symptoms prevailing throughout the duration of the entire 2009 – 2017 survey, and that prevalence of ESS among female signal crayfish is correlated with the prevalence of A. astaci infection in the population. The data shows that an increasing proportion of female crayfish suffer from ESS, and have regenerated swimmerets, however, our observations indicate that partially regenerated swimmerets do not fully function during egg hatching. Based on data and observations during the survey, we speculate that low production levels, as indicated by the low catch per unit effort (CPUE), within the Lake Saimaa signal crayfish population could be related to both high A. astaci infection levels and ESS prevalence among females. The former could be causing increasing mortality among adult crayfish and the latter could be lowering Lake Saimaa signal crayfish reproductive output.

scholarly journals Signal crayfish in Lake Saimaa could be maladapted to the local conditions due to Aphanomyces astaci infection: A seven-year study

2016 ◽  
Vol 22 (1) ◽  
pp. 53-60 ◽  
Author(s):  
Japo Jussial ◽  
Vesa Tiitinen ◽  
Lennart Edsman ◽  
Harri Kokko ◽  
Ravi Fotedar
Keyword(s):  
Commercial Fishery ◽  
Total Catch ◽  
Trap Catch ◽  
Local Conditions ◽  
Signal Crayfish ◽  
Aphanomyces Astaci ◽  
Commercial Grade ◽  
Noble Crayfish ◽  
Crayfish Population ◽  
Lake Saimaa

Abstract We conducted a seven-year survey (years 2009 - 2015) of the Lake Saimaa signal crayfish population. Lake Saimaa is the largest single waterbody in Finland, with a productive fishery and crayfishery. The signal crayfish were introduced to Lake Saimaa in mid-1990’s and a commercial fishery was initiated in the mid-2000s. At first, there was a small proportion of noble crayfish among the catch, but after 2007, an acute crayfish plague epidemic eradicated them, and the signal crayfish stock started showing frequent gross symptoms of chronic crayfish plague infection (e.g., melanised lesions, eroded uropods and pleopods, lost appendages with melanised stumps). This stock now shows gross symptoms of the infection at a rate of 45% to 79% of the annual trap catch, in addition to showing signs of eroded swimmeret symdrome (ESS) at a rate of 2.8 to 15.4%. The CPUE has remained rather low, between one and three crayfish throughout the survey, while the proportion of the commercial grade catch has been between 35% and 68% of the total catch. The signal crayfish populations in Lake Saimaa are still rather fragmented, and production is low. It appears that the Lake Saimaa signal crayfish population has developed slowly and is producing less than expected.

scholarly journals Simultaneous detection of invasive signal crayfish, endangered white-clawed crayfish and the crayfish plague pathogen using environmental DNA

2018 ◽  
Author(s):  
Chloe Victoria Robinson ◽  
Tamsyn M. Uren Webster ◽  
Joanne Cable ◽  
Joanna James ◽  
Sofia Consuegra
Keyword(s):  
Native Species ◽  
Simultaneous Detection ◽  
Environmental Dna ◽  
Conservation Strategies ◽  
Accurate Information ◽  
Essential Information ◽  
Signal Crayfish ◽  
Aphanomyces Astaci ◽  
Field Samples ◽  
Native Crayfish

ABSTRACTAquatic Invasive Species (AIS) are important vectors for the introduction of novel pathogens which can, in turn, become drivers of rapid ecological and evolutionary change, compromising the persistence of native species. Conservation strategies rely on accurate information regarding presence and distribution of AIS and their associated pathogens to prevent or mitigate negative impacts, such as predation, displacement or competition with native species for food, space or breeding sites. Environmental DNA is increasingly used as a conservation tool for early detection and monitoring of AIS. We used a novel eDNA high-resolution melt curve (HRM) approach to simultaneously detect the UK endangered native crayfish (Austropotamobius pallipes), the highly invasive signal crayfish (Pacifastacus leniusculus) and their dominant pathogen, Aphanomyces astaci, (causative agent of crayfish plague). We validated the approach with laboratory and field samples in areas with known presence or absence of both crayfish species as well as the pathogen, prior to the monitoring of areas where their presence was unknown. We identified the presence of infected signal crayfish further upstream than previously detected in an area where previous intensive eradication attempts had taken place, and the coexistence of both species in plague free catchments. We also detected the endangered native crayfish in an area where trapping had failed. With this method, we could estimate the distribution of native and invasive crayfish and their infection status in a rapid, cost effective and highly sensitive way, providing essential information for the development of conservation strategies in catchments with populations of endangered native crayfish.

The spatial distribution of Aphanomyces astaci genotypes across Europe: introducing the first data from Ukraine

2020 ◽  
Vol 25 (1) ◽  
pp. 77-87 ◽  
Author(s):  
Elena Ungureanu ◽  
Michaela MojŽiŠovÁ ◽  
Michiel Tangerman ◽  
Mihaela C. Ion ◽  
Lucian Parvulescu ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Middle East ◽  
Eastern Europe ◽  
Pacifastacus Leniusculus ◽  
Signal Crayfish ◽  
Aphanomyces Astaci ◽  
Western Palaearctic ◽  
Native Crayfish ◽  
Available Information ◽  
Mass Mortalities

Abstract Aphanomyces astaci is the causative agent of crayfish plague, a disease responsible for numerous mass mortalities of native crayfish across Europe. In this study, we aim to extend knowledge about the A. astaci distribution in Eastern Europe, with specific focus on the River Dnieper (Ukraine), and summarize presently available information about the distribution of genotypes of this pathogen across the Western Palaearctic. We compiled published records about genotype groups of A. astaci, assembled them to a comprehensive map, and added the newly obtained results from Ukraine. The native narrow-clawed crayfish Pontastacus leptodactylus was sampled from the river Dnieper in Svydivok and Kiev, ca 170 km apart, and screened for the pathogen presence in soft cuticles by quantitative PCR. We confirmed infections by A. astaci at both sites, with prevalence exceeding 30% and low to medium agent levels in infected crayfish. Pathogen genotyping confirmed the presence of the A. astaci haplogroup B, associated with the signal crayfish Pacifastacus leniusculus but also known from some chronically infected narrowclawed crayfish from Turkey and Moldova. Our results support the notion that latent A. astaci infections among narrow-clawed crayfish populations may be widespread in Eastern Europe and the Middle East.

scholarly journals Should Redclaw Crayfish be introduced to Fiji?

1995 ◽  
Vol 2 (4) ◽  
pp. 312
Author(s):  
Roger Lowery
Keyword(s):  
Pacifastacus Leniusculus ◽  
River Systems ◽  
Cherax Quadricarinatus ◽  
Austropotamobius Pallipes ◽  
Aphanomyces Astaci ◽  
Large Populations ◽  
New Locations ◽  
The Uk ◽  
Native Crayfish ◽  
Redclaw Crayfish

Whenever a new organism comes on the aquaculture scene there is a rush to try it out and to introduce the species to new locations. Such was the case with Pacifastacus leniusculus in Europe in the early 1980s. In the UK there was at the time no legislation to control such introductions and commercial pressures ensured that the species was soon widely distributed throughout the UK. One consequence was the introduction of the Crayfish Plague Aphanomyces astaci which resulted in the destruction of large populations of the native crayfish Austropotamobius pallipes in several river systems. It was against this background that I came to learn of a proposal to introduce Cherax quadricarinatus to Fiji in 1991. The commercial proposal was put to the Department of Fisheries who were considering accepting it when, on the basis of experience with crayfish in the UK, I proposed that there should be a delay while the species was evaluated for its likely effect on the Fijian fauna.

How Molecular Epidemiology Can Affect Tuberculosis Control in the Middle East Countries: A Systematic Review and Meta-Analysis

2020 ◽  
Vol 20 ◽  
Author(s):  
Mohammad Asgharzadeh ◽  
Jalil Rashedi ◽  
Behroz Mahdavi Poor ◽  
Hossein Samadi kafil ◽  
Hossein Moharram Zadeh ◽  
...  
Keyword(s):  
Middle East ◽  
Molecular Epidemiology ◽  
Average Rate ◽  
Meta Analysis ◽  
Close Monitoring ◽  
Drug Resistant ◽  
Middle East Countries ◽  
Virulent Strains ◽  
Recent Transmission ◽  
Highly Virulent

: Nowadays, due to the incidence of specific strains of Mycobacterium tuberculosis and also increase the rate of drug resistant-TB mortality rate has elevated by this disease. Identification of common strains in the region as well as sources of transmission are essential to control the disease that this has been possible by using molecular epidemiology. In this survey, studies which have been carried out based on spoligotyping method in Muslim Middle East countries were considered to determine their role in control of TB. All studies conducted from 2005 to June 2016 were considered systematically in three electronic data bases and finally, 23 studies were selected. The average rate of clustering was 84% and the rate of recent transmission was variable from 21.7% to 92.4%. Incidence of Beijing strains was been rising in the considered countries. In Iran and Saudi Arabia which are immigration and labour-hosting countries, respectively, rapid transmittable strains and drug resistant Beijings were higher than other considered countries. Considering the incidence of highly virulent strains, due to the increase of immigration and people infected with HIV, tuberculosis, especially drug resistant form, the lack of close monitoring in the future will be induce trouble.

scholarly journals Diarylureas: Repositioning from Antitumor to Antimicrobials or Multi-Target Agents against New Pandemics

Antibiotics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 92 ◽  
Author(s):  
Alessia Catalano ◽  
Domenico Iacopetta ◽  
Michele Pellegrino ◽  
Stefano Aquaro ◽  
Carlo Franchini ◽  
...  
Keyword(s):  
Anticancer Agents ◽  
Kinase Inhibitors ◽  
Viral Infections ◽  
Drug Repositioning ◽  
Biological Activities ◽  
Antiviral Treatment ◽  
Far East ◽  
Mild Disease ◽  
To Come ◽  
The Uk

Antimicrobials have allowed medical advancements over several decades. However, the continuous emergence of antimicrobial resistance restricts efficacy in treating infectious diseases. In this context, the drug repositioning of already known biological active compounds to antimicrobials could represent a useful strategy. In 2002 and 2003, the SARS-CoV pandemic immobilized the Far East regions. However, the drug discovery attempts to study the virus have stopped after the crisis declined. Today’s COVID-19 pandemic could probably have been avoided if those efforts against SARS-CoV had continued. Recently, a new coronavirus variant was identified in the UK. Because of this, the search for safe and potent antimicrobials and antivirals is urgent. Apart from antiviral treatment for severe cases of COVID-19, many patients with mild disease without pneumonia or moderate disease with pneumonia have received different classes of antibiotics. Diarylureas are tyrosine kinase inhibitors well known in the art as anticancer agents, which might be useful tools for a reposition as antimicrobials. The first to come onto the market as anticancer was sorafenib, followed by some other active molecules. For this interesting class of organic compounds antimicrobial, antiviral, antithrombotic, antimalarial, and anti-inflammatory properties have been reported in the literature. These numerous properties make these compounds interesting for a new possible pandemic considering that, as well as for other viral infections also for CoVID-19, a multitarget therapeutic strategy could be favorable. This review is meant to be an overview on diarylureas, focusing on their biological activities, not dwelling on the already known antitumor activity. Quite a lot of papers present in the literature underline and highlight the importance of these molecules as versatile scaffolds for the development of new and promising antimicrobials and multitarget agents against new pandemic events.

Respiratory load compensation in chronic airway obstruction

1985 ◽  
Vol 59 (6) ◽  
pp. 1947-1954 ◽  
Author(s):  
M. Lopata ◽  
E. Onal ◽  
G. Cromydas
Keyword(s):  
Airway Obstruction ◽  
Lung Volume ◽  
Average Rate ◽  
Minute Ventilation ◽  
Force Output ◽  
Transdiaphragmatic Pressure ◽  
Load Compensation ◽  
Group A ◽  
Group B ◽  
Chronic Airway

To assess respiratory neuromuscular function and load compensating ability in patients with chronic airway obstruction (CAO), we studied eight stable patients with irreversible airway obstruction during hyperoxic CO2 rebreathing with and without a 17 cmH2O X l-1 X s flow-resistive inspiratory load (IRL). Minute ventilation (VE), transdiaphragmatic pressure (Pdi), and diaphragmatic electromyogram (EMGdi) were monitored. Pdi and EMGdi were obtained via a single gastroesophageal catheter with EMGdi being quantitated as the average rate of rise of inspiratory (moving average) activity. Based on the effects of IRL on the Pdi response to CO2 [delta Pdi/delta arterial CO2 tension (PaCO2)] and the change in Pdi for a given change in EMGdi (delta Pdi/delta EMGdi) during rebreathing, two groups could be clearly identified. Four patients (group A) were able to increase delta Pdi/delta PaCO2 and delta Pdi/delta EMGdi, whereas in the other four (group B) the IRL responses decreased. All group B patients were hyperinflated having significantly greater functional residual capacity (FRC) and residual volume than group A. In addition the IRL induced percent change in delta Pdi/delta PaCO2, and delta VE/delta PaCO2 was negatively correlated with lung volume so that in the hyperinflated group B the higher the FRC the greater was the decrease in Pdi response due to IRL. In both groups the greater the FRC the greater was the decrease in the ventilatory response to loading. Patients with CAO, even with severe airways obstruction, can effect load compensation by increasing diaphragmatic force output, but the presence of increased lung volume with the associated shortened diaphragm prevents such load compensation.

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