Mass mortality events associated with cyprinid herpesvirus 2 (CyHV-2) infection in wild Prussian carp Carassius gibelio in the Netherlands, and molecular biology of virus strains.

In 2011 and 2015, four mass mortalities of Prussian carp (Carassius gibelio) were observed in a recreational freshwater lake and open freshwater in the western part of the Netherlands. Cyprinid herpesvirus 2 (CyHV-2) infection was suspected in these cases, based on presumptive gross diagnosis. To elucidate the cause of the mass mortalities diagnostic PCR assays were performed for CyHV-2, based on the helicase gene.

Molecular Characterization of Strain Isolated from Yellow Mealworms, , in The Netherlands.

Insect culture has developed rapidly worldwide; it faces important security and safety control issues, including animal infections and disease development. In the Netherlands, in 2021, a ~30% mortality of mealworms, , occurred at one farm, where over-humid sites in the substrate were observed. Bacterial cultures from both the external and internal partsof fry and larger mealworms were identified by MALDI-TOF to predominantly and .

Epidemiological cut-off values for Vibrio anguillarum MIC and disc diffusion data generated by standardised methods.

This work aims to generate the data needed to set epidemiological cut-off values for minimum inhibitory concentration (MIC) and disc-diffusion zone measurements of Vibrio anguillarum. A total of 261 unique isolates were tested, applying standard methods specifying incubation at 28°C for 24-28 h. Aggregated MIC distributions for a total of 247 isolates were determined in 9 laboratories for 11 agents.

Fast and accurate identification by MALDI-TOF of the zoonotic serovar E of Vibrio vulnificus linked to eel culture.

Vibrio vulnificus is a zoonotic pathogen that can cause death by septicaemia in farmed fish (mainly eels) and humans. The zoonotic strains that have been isolated from diseased eels and humans after eel handling belong to clade E (or serovar E (SerE)), a clonal complex within the pathovar (pv.) piscis.

Ranavirus genotypes in the Netherlands and their potential association with virulence in water frogs (Pelophylax spp.).

Ranaviruses are pathogenic viruses for poikilothermic vertebrates worldwide. The identification of a common midwife toad virus (CMTV) associated with massive die-offs in water frogs (Pelophylax spp.) in the Netherlands has increased awareness for emerging viruses in amphibians in the country.

Importation of CyHV-2-infected goldfish into the Netherlands.

Cyprinid herpesvirus 2 (CyHV-2) is known as the causative agent of herpesviral haematopoietic necrosis in goldfish Carassius auratus auratus. However, the virus has also been detected in Prussian carp C. gibelio and crucian carp C.

Phylogeny of the infectious hematopoietic necrosis virus in European aquaculture.

Infectious hematopoietic necrosis (IHN)-a highly lethal infectious salmonid disease-has caused substantial economic losses in the European production of rainbow trout (Oncorhynchus mykiss) since the late 1980s. The causal agent of IHN is the IHN virus (IHNV) introduced from overseas. However, until today, its phylogeographic spread in Europe remains poorly understood.

Complete Genome Sequence of , Isolated from a Strawberry Poison Frog () Imported from Nicaragua into the Netherlands.

was isolated from a strawberry poison frog () imported from Nicaragua via Germany to the Netherlands, and its complete genome sequence was determined. isolate /2015/Netherlands/UU3150324001 is 107,183 bp long and has a nucleotide similarity of 98.26% to the reference isolate.

Chromosome-Based blaOXA-48-Like Variants in Shewanella Species Isolates from Food-Producing Animals, Fish, and the Aquatic Environment.

Carbapenems are considered last-resort antibiotics in health care. Increasing reports of carbapenemase-producing bacteria in food-producing animals and in the environment indicate the importance of this phenomenon in public health. Surveillance for carbapenemase genes and carbapenemase-producing bacteria in Dutch food-producing animals, environmental freshwater, and imported ornamental fish revealed several chromosome-based bla-like variants in Shewanella spp.

Complete genome sequence of a common midwife toad virus-like ranavirus associated with mass mortalities in wild amphibians in the Netherlands.

A ranavirus associated with mass mortalities in wild water frogs (Pelophylax spp.) and other amphibians in the Netherlands since 2010 was isolated, and its complete genome sequence was determined. The virus has a genome of 107,772 bp and shows 96.

Evolutionary dynamics and genetic diversity from three genes of Anguillid rhabdovirus.

Wild freshwater eel populations have dramatically declined in recent past decades in Europe and America, partially through the impact of several factors including the wide spread of infectious diseases. The anguillid rhabdoviruses eel virus European X (EVEX) and eel virus American (EVA) potentially play a role in this decline, even if their real contribution is still unclear. In this study, we investigate the evolutionary dynamics and genetic diversity of anguiillid rhabdoviruses by analysing sequences from the glycoprotein, nucleoprotein and phosphoprotein (P) genes of 57 viral strains collected from seven countries over 40 years using maximum-likelihood and Bayesian approaches.

Thermal preference of juvenile Dover sole (Solea solea) in relation to thermal acclimation and optimal growth temperature.

Dover sole (Solea solea) is an obligate ectotherm with a natural thermal habitat ranging from approximately 5 to 27°C. Thermal optima for growth lie in the range of 20 to 25°C. More precise information on thermal optima for growth is needed for cost-effective Dover sole aquaculture.

Viral diseases of wild and farmed European eel Anguilla anguilla with particular reference to the Netherlands.

Diseases are an important cause of losses and decreased production rates in freshwater eel farming, and have been suggested to play a contributory role in the worldwide decline in wild freshwater eel stocks. Three commonly detected pathogenic viruses of European eel Anguilla anguilla are the aquabirnavirus eel virus European (EVE), the rhabdovirus eel virus European X (EVEX), and the alloherpesvirus anguillid herpesvirus 1 (AngHV1). In general, all 3 viruses cause a nonspecific haemorrhagic disease with increased mortality rates.

Identification and localization of the structural proteins of anguillid herpesvirus 1.

Many of the known fish herpesviruses have important aquaculture species as their natural host, and may cause serious disease and mortality. Anguillid herpesvirus 1 (AngHV-1) causes a hemorrhagic disease in European eel, Anguilla anguilla. Despite their importance, fundamental molecular knowledge on fish herpesviruses is still limited.

The alloherpesviral counterparts of interleukin 10 in European eel and common carp.

Viral interleukin 10 (IL-10) like open reading frames have been identified in several pox- and herpesviruses, including the fish herpesviruses Anguillid herpesvirus 1 (AngHV-1) and Cyprinid herpesvirus 3 (CyHV-3). European eel (Anguilla anguilla) IL-10 was sequenced, in order to compare European eel and common carp (Cyprinus carpio) IL-10 with their alloherpesviral counterparts. Homology between the virus and host IL-10 amino acid sequences is low, which is confirmed by phylogenetic analysis.

[Zoonotic bacterium: duty to notify advisable].

Vibrio vulnificus is a zoonotic bacterium that can be found in raw fish (mainly eel and oysters) and seawater. Human infections may extend from wound infections to fasciitis necroticans or primary sepsis with a mortality rate of more than 50%. Although V.

Development and validation of a two-step real-time RT-PCR for the detection of eel virus European X in European eel, Anguilla anguilla.

Eel virus European X (EVEX) is one of the most common pathogenic viruses in farmed and wild European eel (Anguilla anguilla) in the Netherlands. The virus causes a hemorrhagic disease resulting in increased mortality rates. Cell culture and antibody-based detection of EVEX are laborious and time consuming.

Complete genome sequence and taxonomic position of anguillid herpesvirus 1.

Eel herpesvirus or anguillid herpesvirus 1 (AngHV1) frequently causes disease in freshwater eels. The complete genome sequence of AngHV1 and its taxonomic position within the family Alloherpesviridae were determined. Shotgun sequencing revealed a 249 kbp genome including an 11 kbp terminal direct repeat that contains 7 of the 136 predicted protein-coding open reading frames.

Pathogenesis of Herpesvirus anguillae (HVA) in juvenile European eel Anguilla anguilla after infection by bath immersion.

A clinical infection in post-larval (glass) European eels Anguilla anguilla was successfully induced after artificial bath immersion with Herpesvirus anguillae (HVA), isolated from diseased European eel. HVA caused a clinical infection after 7 d post-inoculation (pi); virus was detected by polymerase chain reaction (PCR) from Day 1 pi; virus isolation was positive from Day 7 pi, and HVA antigen was detected by immunohistochemistry in gills and stomach from Day 4 pi. Tissue changes were found by histological examination in gills and skin from Day 4 pi.

HRT and nutrients affect bacterial communities grown on recirculation aquaculture system effluents.

In a recirculation aquaculture system the drumfilter effluent can be used as substrate for heterotrophic bacterial production, which can be recycled as feed. Because the bacteria might contain pathogens, which could reduce its suitability as feed, it is important to characterize these communities. Bacteria were produced in growth reactors under different conditions: 7 h hydraulic retention time (HRT) vs.

Development of a polymerase chain reaction for the detection of Anguillid herpesvirus DNA in eels based on the herpesvirus DNA polymerase gene.

Anguillid herpesvirus (AnHV, also known as Herpesvirus anguillae or HVA) is found in both Japanese and European eels. Based on restriction enzyme analysis a small number of differences were found between AnHV isolated from Japanese eels and from European eels. The total genome size of both is about 245 kb, which is confirmed by alternating-field electrophoresis.