High prevalence of Paramarteilia canceri infecting velvet swimming crabs Necora puber in Ireland (original) (raw)

A preliminary health survey of the hermit crab, Pagurus bernhardus, on the southwest coast of Ireland

Journal of Invertebrate Pathology, 2015

During October and November of 2011 and 2012, 229 hermit crabs, Pagurus bernhardus, were randomly collected from the intertidal shore at three locations along the southwest coast of Ireland. This is the first survey to assess the health status of this crustacean in Ireland. Carapace length and the sex of each crab were recorded. Crabs were screened for parasites by histology and the intensity and prevalence of infection was determined. Crabs of varying carapace length were screened. The only parasite observed in the crabs was Microphallus sp., the first record of this digenetic trematode in P. bernhardus in Europe.

Disease profiles of juvenile edible crabs (Cancer pagurus L.) differ at two geographically-close intertidal sites

Journal of Invertebrate Pathology, 2015

The prevalence of disease in edible crabs (Cancer pagurus) was assessed at two sites in South West Wales; one estuarine (Pembroke Ferry) and another facing open water (Freshwater East). Diseases included pink crab disease caused by Hematodinium sp., an infection of the antennal gland caused by Paramikrocytos canceri and an idiopathic inflammatory condition of the connective tissue surrounding the anterior ganglionic masses. This latter condition was only found in crabs from Pembroke Ferry. There was a significantly higher prevalence of pink crab disease at Freshwater East than Pembroke Ferry, although both sites had similar levels of infection by P. canceri.

APPLIED ASPECTS OF MARINE PARASITOLOGY Proceedings of the International Workshop on Marine Parasitology

2008

Interdisciplinarity in marine parasitology. 7 KEN MACKENZIE Marine parasites as biological tags in European waters: two successful EU-funded multidisciplinary projects. 15 GRAÇA COSTA Marine parasitology in Portugal. 21 KEN MACKENZIE Marine parasites as indicators of pollution. 27 BJØRN BERLAND Methodology to prepare whole mounts: shortcuts. 33 KEVIN LAFFERTY Infectious disease trends in natural marine communities. 37 MÁRIO GEORGE-NASCIMENTO The use of marine parasites in fish population studies. 39 MARIA JOÃO SANTOS, AURÉLIA SARAIVA & BJØRN BERLAND Laboratory procedures to study fish parasitology. 41 JANINE CAIRA Metazoan parasites as indicators of elasmobranch biology. 43 LUISA MONTEIRO Parasites as cause of rejection in portuguese fish markets. 45 PAULA RAMOS Fish quality regulation and legislation. 47 ISABEL AFONSO-DIAS Visit to the fish market. 49

Epidemiology and dynamics of shell disease in the edible crab Cancer pagurus:a preliminary study of Langland Bay, Swansea, UK

Diseases of Aquatic Organisms, 1999

The prevalence and severity of shell disease in the edible crab Cancer pagurus (L.) was investigated in animals collected from Langland Bay, Gower, South Wales, UK, at monthly intervals from 1997 to 1998. Shell disease is the progressive degradation of exoskeletal chitin accompanied by melanisation of the affected region. Over 50% of the crabs sampled had 1 or more black-spot lesions. The proportion of exoskeleton affected increased with the size of the crab. Male crabs showed significantly higher levels of the disease than females, a higher prevalence of black-spot lesions (63% in males, 40% in females) and a higher mean percentage of body covered by lesions (1 % in males, 0.2% in females). This difference between the sexes corresponded to an increase in ventral surface and chela infection in males. For both sexes, the dorsal carapace was the area most affected by the disease. Dorsal carapace regional breakdown revealed the areas most commonly affected were located to the posterior of the crab. Lesion location patterns suggested that sand abrasion injuries during back-burrowing behaviour of C. pagurus lead to the formation of shell disease lesions. Seasonal trends in shell disease were seen to be dependent on the onshore migration patterns of the different size classes and sexes over the sampling period.

The potential impact of climate change on the infectious diseases of commercially important shellfish populations in the Irish Sea--a review

ICES Journal of Marine Science, 2014

The Irish Sea and surrounding regions are a rich source of shellfish production as a result of captive fishing and aquaculture. Key species produced include lobsters (Homarus gammarus), edible crabs (Cancer pagurus), langoustines (Nephrops norvegicus), flat oysters (Ostrea edulis), cockles (Cerestoderma edule) and blue mussels (Mytilus edulis). The role played by infectious disease in limiting the sustainability of the production of these species is largely neglected. This review summarizes our knowledge of the key diseases of commercially important crustaceans and bivalve molluscs and attempts to determine their role in limiting the population of animals available for food production both at present and in the future. It shows that the key diseases threatening the sustainability of shellfish production are bitter crab disease in langoustines and edible crabs, and a wide range of diseases caused by micro- and macro-parasites in some bivalve molluscs including oysters and cockles. Oc...

Factors contributing to the disease ecology of brown crab (Cancer pagurus) in a temperate marine protected area

2020

Marine ecosystems are affected by multiple, well-known stressors like fishing and climate change, but a less documented concern is disease. Marine reserves have been successful in replenishing stocks and aiding recruitment but studies have shown that high population abundances in marine reserves may lead to unwanted secondary effects such as increase in predators and competition, altering trophic webs, and disease. Here, we investigate factors contributing to disease prevalence in a brown crab (Cancer pagurus) population around Lundy Island (the UK's first MPA) after 7 years of no-take protection. Population parameters (size, sex, and abundance), disease (shell disease, Hematodinium spp. infection) and injury presence (a known precursor to some disease conditions) were assessed over two years in both fished and unfished areas of the MPA. We found no significant difference in prevalence between the disease prevalence in fished and unfished areas, however overall, the number of in...

Fecampia erythrocephala rediscovered: prevalence and distribution of a parasitoid of the European shore crab, Carcinus maenas

Journal of the Marine Biological Association of the UK, 2002

An ecological assessment of Fecampia erythrocephala, reporting its habitat distribution, abundance, host specificity, size-specific prevalence, frequency distribution among hosts, effect on host growth, and its site specificity within these hosts is presented. At the Isle of Man and near Plymouth, Fecampia erythrocephala cocoons were generally abundant on the undersides of rocks in the Ascophyllum and Fucus serratus zones. Infected crabs were also most common in these habitats. Both Carcinus maenas and Cancer pagurus were parasitized at similar prevalences, although the former species was relatively much more common in the habitats where the worm cocoons were abundant. Fecampia erythrocephala did not infect crabs larger than 11 mm carapace width, and prevalence decreased significantly with crab size. Prevalences reached 11% in areas where cocoons were abundant. Together with the large size of these worms relative to the size of the host crabs and the observations on worm emergence, ...

The effect of Sacculina carcini infections on the fouling, burying behaviour and condition of the shore crab, Carcinus maenas Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark

Marine Biology Research - MAR BIOL RES, 2006

Crabs infected by rhizocephalans usually do not moult. Because moulting is the ultimate defence against fouling epibionts, infected as opposed to uninfected crabs can be expected to harbour a diversity of hard-bottom organisms on their cuticula. Here we provide unequivocal evidence that this is the case in the Carcinus maenas ÁSacculina carcini association. In a Danish sample of shore crabs, 75% of sacculinized individuals harboured macroscopic epibionts, whereas only 29% of the uninfected crabs were colonized. The mean numbers of fouling barnacles and serpulid tubeworms per individual were 7.7 and 47.3 for uninfected and infected crabs, respectively, corresponding to coverage of the cuticula by 0.7 and 5.4%. Infected crabs were 12% lower in tissue dry weight than uninfected individuals, which may be a factor causing the moult of sacculinized crabs to be postponed. Finally, a laboratory experiment suggested that infected crabs are less likely to bury than uninfected specimens. Because burying is an important fouling defence, such a parasite-induced behavioural change will favour the colonization by epibionts. It is argued that rhizocephalans infecting crabs from soft-bottom communities may indirectly affect the structure of the free-living benthic community by adding hard-bottom species that otherwise would be absent.

Infection of juvenile edible crabs, Cancer pagurus by a haplosporidian-like parasite

Journal of Invertebrate Pathology, 2013

This study aimed to examine the pathobiology of a haplosporidian-like infection in juvenile (pre-recruit) edible crabs (Cancer pagurus) from two locations in South West Wales, UK. Infected crabs showed no external symptoms of the disease but dissection revealed an infected and hypertrophic antennal gland. Histological examination showed extensive parasitisation of the antennal gland overlying the hepatopancreas. Heavily infected crabs also showed the presence of parasites with morphological similarities to Haplosporidia in the labyrinth of the antennal gland and in the gills. The spread of the infection from the antennal gland to the gills suggests that these parasites are released into the haemolymph. Attempts to characterise the haplosporidian-like organism using several primers previously shown to amplify members of the phylum Haplosporidia failed. The prevalence of infection in juvenile edible crabs varied throughout the sampling period of November 2011 to July 2012 with the lowest level of ca. 15% in November peaking at 70% in March. This parasite may represent a threat to the sustainability of edible crab fisheries in this region if the damage observed in the antennal gland and gills results in host mortality. The identification of these parasites as members of the phylum Haplosporidia based on morphology alone must be seen as tentative in the absence of sequence data.

Prevalence and histopathology of the parasitic barnacle, Sacculina carcini in shore crabs, Carcinus maenas

Journal of Invertebrate Pathology

Sacculina carcini is a common parasite of the European shore crab, Carcinus maenas. Following successful penetration of the host, numerous rootlets are formed that permeate through the hosts' tissues. Ultimately, these form an externa that houses the developing nauplii larvae of the parasite. Most studies have quantified levels of infection by counting the presence of reproductive externae and their breakdown structures, called scars. However, the diagnosis of the disease based only on external features may lead to underreporting the prevalence of the parasite. In the current study, we examined the presence and severity of S. carcini in C. maenas (n = 221) in the Prince of Wales Dock, South Wales, U.K. using a range of diagnostic approaches to give an accurate representation of temporal dynamics of infection. Parasitized crabs were found with a mean prevalence of 24% as determined by histological examination of the hepatopancreas. However, the prevalence of S. carcini based on the presence of externae and scars was only 6.3% and 1.8%, respectively. Overall, parasitism was associated with smaller crabs, crabs later in the moulting cycle that were orange in colour (as opposed to green or yellow), and those with a higher number of bacteria in the haemolymph. Interestingly, only 7.5% of infected crabs showed evidence of distinct host (cellular) response to the presence of rootlets in the hepatopancreas.