New Insights on the Diversity, Ecology and Genetic Population Structure of spp. from Fish and Cetacean Hosts from Northeast Atlantic Waters.

In the last 25 years, nematode parasites of the genus have attracted international attention from various socio-economic sectors, with serious concern about the impact of these parasites on seafood quality and safety, and public health (related to both zoonoses and allergy). A knowledge-based understanding of the population structure of spp. is useful to provide valuable data about the infection dynamics, host specificity and its ability to adapt to local environments and to climate change by adapting to the food-web structure.

Fish feed composition by high-throughput sequencing analysis: Parasite risk assessment.

The use of wild small fish species as feed for aquaculture has clearly an economic incentive by speeding the growth of farmed species. Since feed ingredients are sourced from wild fisheries the farmed species could contain natural contaminants which may introduce food safety concerns. In this study, we used High-Throughput Sequencing (HTS) to explore the whole DNA profile of ten dry commercial feeds commonly used by Spanish fish farming companies.

Population Genetic Structure of Infecting the European Hake from North East Atlantic Fishing Grounds.

The European hake, one of the most commercially valuable species in ICES fishing areas, is considered an important neglected source of zoonotic risk by nematode parasites belonging to the genus . is, by far, the most important host of spp. at the European fishing grounds, in terms of demographic infection values, and carries the highest parasite burden.

Risk-based scoring and genetic identification for anisakids in frozen fish products from Atlantic FAO areas.

Background: The presence of Anisakis larvae in fish represents a major public health concern. Effective risk management procedures should be applied to prevent heavily infected products from reaching the market. The aim of the study is to provide preliminary data on parasite exposure and risk classification in frozen fish products by applying a risk categorization scheme (site, abundance, density and epidemiology - SADE) and Fish Parasite Rating (FPR) method.

Occurrence of Anisakis and Hysterothylacium larvae in commercial fish from Balearic Sea (Western Mediterranean Sea).

This study investigates the occurrence of anisakids and raphidascarids in commercial fish from Balearic Sea (Western Mediterranean). A total of 335 fish including 19 black anglerfish (Lophius budegassa), 33 white anglerfish (L. piscatorius), 129 European hake (Merluccius merluccius), 30 red mullet (Mullus barbatus), and 124 striped mullet (M.

Molecular identification of Anisakis and Hysterothylacium larvae in commercial cephalopods from the Spanish Mediterranean coast.

This study aims to investigate the occurrence of nematode larvae in commercial cephalopods in the Western Mediterranean Sea. A total of 202 animals comprising 123 broadtail shortfin squid (Illex coindetii), 34 European squid (Loligo vulgaris) and 45 common octopus (Octopus vulgaris) were examined using enzymatic digestion. A total of 31 larvae were isolated (prevalence: 14.

Perkinsus olseni and P. chesapeaki detected in a survey of perkinsosis of various clam species in Galicia (NW Spain) using PCR-DGGE as a screening tool.

A survey on perkinsosis was performed involving 15 locations scattered along the Galician coast (NW Spain) and four clam species with high market value (Ruditapes decussatus, Ruditapes philippinarum, Venerupis corrugata and Polititapes rhomboides). The prevalence of Perkinsus parasites was estimated by PCR using genus-specific primers. The highest percentage of PCR-positive cases for perkinsosis corresponded to clams R.

Update of information on perkinsosis in NW Mediterranean coast: Identification of Perkinsus spp. (Protista) in new locations and hosts.

This study addressed perkinsosis in commercially important mollusc species in the western Mediterranean area. Perkinsus olseni was found in Santa Gilla Lagoon (Sardinia) infecting Ruditapes decussatus, Cerastoderma glaucum and Venerupis aurea, in Balearic Islands infecting Venus verrucosa and in Delta de l'Ebre (NE Spain) parasitising Ruditapes philippinarum and R. decussatus.

Oyster parasites Bonamia ostreae and B. exitiosa co-occur in Galicia (NW Spain): spatial distribution and infection dynamics.

Bonamiosis constrains the flat oyster industry worldwide. The protistan species Bonamia ostreae had been considered solely responsible for this disease in Europe, but the report of B. exitiosa infecting Ostrea edulis 5 yr ago in Galicia (NW Spain), and subsequently in other European countries, raised the question of the relevance of each species in bonamiosis.

Species-specific oligonucleotide probe for detection of Bonamia exitiosa (Haplosporidia) using in situ hybridisation assay.

Bonamiosis is a disease affecting various oyster species and causing oyster mass mortalities worldwide. The protozoans Bonamia exitiosa and B. ostreae (Haplosporidia) are included in the list of notifiable diseases of the World Organisation for Animal Health as the causative agents of this disease.

Infection of Manila clams Ruditapes philippinarum from Galicia (NW Spain) with a Mikrocytos-like parasite.

The name 'microcells' is frequently used to refer to small-sized unicellular stages of molluscan parasites of the genera Bonamia (Rhizaria, Haplosporidia) and Mikrocytos (Rhizaria). Histological examination of Manila clams Ruditapes philippinarum revealed microcells in the connective tissue of adductor muscle, foot, mantle, gills, siphon and visceral mass. The clams had been collected from 4 beds on the coast of Galicia, Spain.

Role of microRNAs in the immunity process of the flat oyster Ostrea edulis against bonamiosis.

MicroRNAs (miRNAs) are small (∼22nt) non-coding regulatory single strand RNA molecules that reduce stability and/or translation of sequence-complementary target. miRNAs are a key component of gene regulatory networks and have been involved in a wide variety of biological processes, such as signal transduction, cell proliferation and apoptosis. Many miRNAs are broadly conserved among the animal lineages and even between invertebrates and vertebrates.

Cockle Cerastoderma edule fishery collapse in the Ría de Arousa (Galicia, NW Spain) associated with the protistan parasite Marteilia cochillia.

The highest shellfishery catch in Galicia (NW Spain) has traditionally been cockle Cerastoderma edule. The shellfish bed located in Lombos do Ulla (Ría de Arousa) used to be among those with the highest cockle production; however, cockle mortality rate increased sharply in this bed in April 2012, reaching 100% in May 2012. Salinity and temperature were discounted as potential causes of the mortality.

Cloning and characterization of neoplasia-related genes in flat oyster Ostrea edulis.

Bonamiosis and disseminated neoplasia (DN) are the most important diseases affecting cultured flat oysters Ostrea edulis in Galicia (NW Spain). Previous research using suppresive substraction hybridisation that had been performed addressing the molecular basis of DN as well as the induction and development of the disease in oysters, yielded the whole open reading frame of nine genes: XBP-1, RACK, NDPk, C1qTNF, RPA3, SAP18, p23, ubiquitin and ferritin. These nine genes were characterized in this study.

A scoring system approach for the parasite predictive assessment of fish lots: a proof of concept with anisakids.

A total of 982 individuals distributed in 11 lots belonging to 10 fish species from three Atlantic FAO fishing areas were sampled and examined to detect the presence of anisakid larvae in fish muscle. After hazard identification by genetic sequencing and exposure assessment by anatomic extent and demographic characterization of infection, all data were fitted for each fish species to a new proposed scoring schema of parasite prediction. In the absence of a criterion standard method for inspection and precise definition of the quantum satis for parasites in contaminated fish lots, the inspection rating scheme called SADE (Site of infection, Assurance of quality, Demography, Epidemiology) may help fish industries to precisely handle and to evaluate the likely outcome of infected fish lots after being diagnosed.

Molecular characterisation of TNF, AIF, dermatopontin and VAMP genes of the flat oyster Ostrea edulis and analysis of their modulation by diseases.

Bonamiosis and disseminated neoplasia (DN) are the most important diseases affecting cultured flat oysters (Ostrea edulis) in Galicia (NW Spain). Previous research of the response of O. edulis against bonamiosis by suppression subtractive hybridisation yielded a partial expressed sequence tag of tumour necrosis factor (TNF) and allograft inflammatory factor (AIF), as well as the whole open reading frame for dermatopontin and vesicle-associated membrane (VAMP).

Species-specific diagnostic assays for Bonamia ostreae and B. exitiosa in European flat oyster Ostrea edulis: conventional, real-time and multiplex PCR.

Bonamia ostreae and B. exitiosa have caused mass mortalities of various oyster species around the world and co-occur in some European areas. The World Organisation for Animal Health (OIE) has included infections with both species in the list of notifiable diseases.

Identification of relevant cancer related-genes in the flat oyster Ostrea edulis affected by disseminated neoplasia.

Disseminated neoplasia (DN), an oyster disease resembling leukaemia, has been reported in a number of species of marine bivalve molluscs. The disease is characterised by a proliferation of abnormal circulating cells of unknown origin resulting in the invasion of tissues and organs, frequently with a fatal end of the affected individuals. To obtain a more comprehensive view of bivalve cancer processes, suppressive subtracted hybridisation (SSH) and quantitative RT-PCR (q-PCR) approaches were combined to investigate changes in the transcriptome of Ostrea edulis haemolymph cells associated to DN.

Comparison of haemocytic parameters among flat oyster Ostrea edulis stocks with different susceptibility to bonamiosis and the Pacific oyster Crassostrea gigas.

Farming of the flat oyster Ostrea edulis in Europe is severely constrained by the protozoan Bonamia ostreae. The introduction of the resistant species Crassostrea gigas has been a relief for the farmers, while the pilot programmes to select O. edulis strains resistant to bonamiosis performed in various countries can be seen as a promising strategy to minimise the effects of bonamiosis.

Identification and expression of immune genes in the flat oyster Ostrea edulis in response to bonamiosis.

The European flat Ostrea edulis is highly susceptible to infection by the protozoan Bonamia ostreae and Bonamia exitiosa, intracellular parasites able to survive and proliferate within the oyster haemocytes. The parasite, once phagocytosed by the haemocyte, the main cellular effector of the immune system, appears to have some counter mechanism that turns off the haemocyte's metabolic destructive capacity, so that the parasite survives within the cell. To further understand the molecular basis of the immune response of the flat oyster against the bonamiosis, suppression subtractive hybridization and Q-PCR approaches were combined to identify genes involved in the development of the infection both in early and advanced phases.

Microsatellite marker development in the protozoan parasite Perkinsus olseni.

The analysis of an enriched partial genomic library and of public expressed sequence tag (EST) resources allowed the characterization of the first microsatellite loci in the protozoan parasite Perkinsus olseni. Clonal cultures from laboratory isolates derived from infected clams Ruditapes decussatus (from Spain), R. philippinarum (from Spain and Japan), and Austrovenus stutchburyi (from New Zealand) were used for the characterization of 12 microsatellites.

Differential diagnosis of Perkinsus species by polymerase chain reaction-restriction fragment length polymorphism assay.

Perkinsosis is an infection of marine molluscs caused by the protistan parasites of the genus Perkinsus, which has been classified by the OIE as a disease that warrants notification. In the present study, we have applied a molecular genetic approach to develop an optional method for the specific identification of Perkinsus species. A species-specific polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay of the rRNA ITS region was developed to identify and distinguish among Perkinsus species.

Molecular cloning and expression analysis of interferon regulatory factor-1 (IRF-1) of turbot and sea bream.

The interferon regulatory factor (IRF) family comprises transcription factors that regulate the expression of interferon and interferon-related cytokines. Using the RACE technique, we have determined the complete cDNA sequence of turbot (Scophthalmus maximus) and sea bream (Sparus aurata) IRFs. These sequences shared characteristics with other IRFs of fish, mammals and birds, and showed high similarity with IRF-1.

Genetic evidence for the existence of sibling species within Contracaecum rudolphii (Hartwich, 1964) and the validity of Contracaecum septentrionale (Kreis, 1955) (Nematoda: Anisakidae).

Specimens of Contracaecum rudolphii sensu lato (s.l.) (Nematoda: Anisakidae) from Phalacrocorax carbo sinensis from northeastern and central Italy were characterised genetically and compared with those from Phalacrocorax aristotelis from Galician coasts, Spain (identified as C.

SSU rDNA analysis of Kudoa rosenbuschi (Myxosporea) from the Argentinean hake Merluccius hubbsi.

The cloning and sequencing of the small subunit (SSU) ribosomal DNA gene from Kudoa rosenbuschi (myxosporean species associated with post-mortem myoliquefaction process in the Argentinean hake Merluccius hubbsi) is reported. The SSU rDNA was found to contain 1740 bp with a single polymorphic site with either a C or T at position 221. The sequence data obtained in this study and those known sequences of Kudoa species deposited in the GenBank were all analyzed to construct a phylogenetic tree.