Search

Harbour seals ( Phoca vitulina ) are the most common pinniped species in the Wadden Sea of Schleswig-Holstein, Hamburg and Lower Saxony, Germany. Their numbers have recovered after significant depletion due to viral outbreaks and effects of anthropogenic activities like pollution and habitat disturbance. Within the Wadden Sea National Park of Lower Saxony the harbour seal is protected. As a top predator in the Wadden Sea ecosystem, the harbour seal is a sentinel species for the state of the environment. Between 2015 and 2017, a total of 80 stranded dead harbour seals were collected along the coastline of Lower Saxony and submitted for pathological investigations. Of these, 70 seals were born in the same year (0-7 months, age group 1) and eight in the previous year (8-19 months, age group 2), due to high mortality rates in these age groups. However, two perennial animals were also available for examination during this period, one of which was in good nutritional condition. Many of the seals that had been mercy-killed and found dead were in poor nutritional status. Histopathological, microbiological, parasitological and virological examinations were conducted on 69 individuals (86% (69/80)) in a suitable state of preservation. Respiratory tract parasitosis, cachexia, and bronchopneumonia were the most common causes of death or disease. Overall, there was no evidence of a relapse of a viral disease outbreak. Macrowaste, such as plastic waste or fishery-related debris, were not found in any gastrointestinal tract of the animals examined. There was also no evidence of grey seal predation. Weakness and cachexia were prominent causes of disease and death in harbour seals found within a few weeks after birth, but bronchopneumonia and septicaemia also developed in slightly older animals. Frequently found microbial pathogens in seals from Lower Saxony were similar to those found in other studies on seals from the Wadden Sea region in Schleswig-Holstein, for example streptococci and Escherichia coli /v. haemolytica , Brucella spp. and Erysipelothrix rhusiopathiae , potentially human pathogenic germs. The results of the examinations of dead harbour seals from Lower Saxony show that pathological investigations on a representative number of animals deliver urgently needed information on the health status of the population. The results represent an important contribution to the state of the top predators of the Wadden Sea as part of the obligations within the Trilateral Wadden Sea Agreement, Oslo and Paris Convention for the Protection of the Marine Environment of the North-East Atlantic (OSPAR) and the Marine Framework Directive. The investigations should be continued as a matter of urgency and the stranding network should be expanded.

A genomic database of all Earth's eukaryotic species could contribute to many scientific discoveries; however, only a tiny fraction of species have genomic information available. In 2018, scientists across the world united under the Earth BioGenome Project (EBP), aiming to produce a database of high-quality reference genomes containing all ~1.5 million recognized eukaryotic species. As the European node of the EBP, the European Reference Genome Atlas (ERGA) sought to implement a new decentralised, equitable and inclusive model for producing reference genomes. For this, ERGA launched a Pilot Project establishing the first distributed reference genome production infrastructure and testing it on 98 eukaryotic species from 33 European countries. Here we outline the infrastructure and explore its effectiveness for scaling high-quality reference genome production, whilst considering equity and inclusion. The outcomes and lessons learned provide a solid foundation for ERGA while offering key learnings to other transnational, national genomic resource projects and the EBP., (© 2024. The Author(s).)

Freshwater fish species are experiencing the highest decline among vertebrates in this century. Although a great effort has been made to identify and tackle threats to the conservation of this taxa, several knowledge gaps still exist particularly for noncommercial endangered species, including considerations regarding fish health status. These species face deteriorating environmental conditions in their natural habitats that may lead to stress and increased risk for infectious disease outbreaks. Establishing health surveillance is crucial to identify and predict physiologic disruption in fish populations. Additionally, information retrieved may be used to direct targeted efforts to contribute to improving the conservation status of these species. We used threatened Iberian leuciscids as a case study to discuss the current knowledge regarding their health surveillance and to suggest recommendations for the establishment of practical health assessments that can benefit conservation plans for these species and be implemented in threatened or endangered freshwater fish species plans globally., (© Wildlife Disease Association 2024.)

Evaluating populational trends of health condition has become an important topic for marine mammal populations under the Marine Strategy Framework Directive (MSFD). In the Baltic Sea, under the recommendation of Helsinki Commission (HELCOM), efforts have been undertaken to use blubber thickness as an indicator of energy reserves in marine mammals. Current values lack geographical representation from the entire Baltic Sea area and a large dataset is only available for grey seals ( Halichoerus grypus ) from Sweden and Finland. Knowledge on variation of blubber thickness related to geography throughout the Baltic Sea is important for its usage as an indicator. Such evaluation can provide important information about the energy reserves, and hence, food availability. It is expected that methodological standardization under HELCOM should include relevant datasets with good geographical coverage that can also account for natural variability in the resident marine mammal populations. In this study, seasonal and temporal trends of blubber thickness were evaluated for three marine mammal species-harbor seal ( Phoca vitulina ), grey seal ( Halichoerus grypus ) and harbor porpoise ( Phocoena phocoena )-resident in the southern Baltic Sea collected and investigated under stranding networks. Additionally, the effects of age, season and sex were analyzed. Seasonal variation of blubber thickness was evident for all species, with harbor seals presenting more pronounced effects in adults and grey seals and harbor porpoises presenting more pronounced effects in juveniles. For harbor seals and porpoises, fluctuations were present over the years included in the analysis. In the seal species, blubber thickness values were generally higher in males. In harbor seals and porpoises, blubber thickness values differed between the age classes: while adult harbor seals displayed thicker blubber layers than juveniles, the opposite was observed for harbor porpoises. Furthermore, while an important initial screening tool, blubber thickness assessment cannot be considered a valid methodology for overall health assessment in marine mammals and should be complemented with data on specific health parameters developed for each species., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Siebert, Grilo, Kesselring, Lehnert, Ronnenberg, Pawliczka, Galatius, Kyhn, Dähne and Gilles.)

Ex situ breeding programs are important conservation tools for endangered freshwater fish. However, developing husbandry techniques that decrease the likelihood of disease, antimicrobial resistance, and virulence determinants acquisition during this process is challenging. In this pilot study, we conducted a captivity experiment with Portuguese nase ( Iberochondrostoma lusitanicum ), a critically endangered leuciscid species, to investigate the influence of simple protective measures (i.e., material disinfection protocols and animal handling with gloves) on the dynamics of a potential pathogenic genus, Aeromonas , as well as its virulence profiles and antimicrobial resistance signatures. Our findings show that antimicrobial resistance in Aeromonas spp. collected from I. lusitanicum significantly increased during the extent of the assay (5 weeks), with all isolates collected at the end of the study classified as multidrug-resistant. Additionally, humans handling fishes without protective measures were colonized by Aeromonas spp. The use of protective measures suggested a decreasing trend in Aeromonas spp. prevalence in I. lusitanicum , while bacterial isolates displayed significantly lower virulence index values when virulence phenotypical expression was tested at 22 °C. Despite this study representing an initial trial, which needs support from further research, protective measures tested are considered a simple tool to be applied in ex situ breeding programs for aquatic animals worldwide. Furthermore, current results raise concern regarding antimicrobial resistance amplification and zoonotic transmission of Aeromonas spp. in aquatic ex situ programs.

Urbanisation and invasion of wildlife into urban areas as well as human leisure activities create diverse wildlife-domestic animal-human interfaces, increasing the risk of (zoonotic) parasite spillover from sylvatic to domestic and synanthropic cycles. This study investigated the endo- and ectoparasite fauna, emphasising on parasites of One Health Concern, of the most common predators in northern Germany between November 2013 and January 2016. Eighty red foxes (Vulpes vulpes), 18 stone martens (Martes foina) and nine raccoon dogs (Nyctereutes procyonoides) were available for the study. Overall, 79 (73.8%) of the examined predators (n=107) harboured at least one endoparasite. The most frequently detected endoparasites in red foxes were Toxocara canis (43.8% positive individuals), Capillaria spp. (36.3%), Alaria alata (25.0%), Echinococcus multilocularis (26.3%) and Uncinaria stenocephala (25.0%). Furthermore, Toxascaris leonina, Trichuris vulpis, Taenia ssp., Mesocestoides spp. and coccidian oocysts were observed. The endoparasite species richness in raccoon dogs was comparable to red foxes, while in stone martens, only Capillaria spp. were found. Muscle digestion for detection of Trichinella spp. and antigen testing for Giardia spp. did not show positive results. Ectoparasite analyses revealed infestations with ticks species of the genus Ixodes as well as Dermacentor reticulatus. Scabies mites were not present in digested skin samples, while Demodex spp. mites were observed by faecal flotation in one red fox. Furthermore, fleas (Archaeopsylla erinacei and Chaetopsylla globiceps) were observed in the fur of red foxes, while lice were not present in any predator species. However, infestation frequency with ectoparasites was with 19.2% generally low in available predator skins (n=99). Overall, the present study showed that predators in northern Germany serve as reservoirs for parasites of One Health concern, with four of the five most frequent endoparasites being zoonotic, highlighting the need of parasite surveillance in wildlife predators in order to implement measures avoiding spillovers to domestic animals and humans., (© 2021. The Author(s).)

Climate change is expected to create environmental disruptions that will impact a wide array of biota. Projections for freshwater ecosystems include severe alterations with gradients across geographical areas. Life traits in bacteria are modulated by environmental parameters, but there is still uncertainty regarding bacterial responses to changes caused by climatic alterations. In this study, we used a river water microcosm model to evaluate how Aeromonas spp., an important pathogenic and zoonotic genus ubiquitary in aquatic ecosystems, responds to environmental variations of temperature and pH as expected by future projections. Namely, we evaluated bacterial growth, biofilm production and antimicrobial resistance profiles of Aeromonas species in pure and mixed cultures. Biofilm production was significantly influenced by temperature and culture, while temperature and pH affected bacterial growth. Reversion of antimicrobial susceptibility status occurred in the majority of strains and tested antimicrobial compounds, with several combinations of temperature and pH contributing to this effect. Current results highlight the consequences that bacterial genus such as Aeromonas will experience with climatic alterations, specifically how their proliferation and virulence and phenotypic resistance expression will be modulated. Such information is fundamental to predict and prevent future outbreaks and deleterious effects that these bacterial species might have in human and animal populations.

Assessments regarding health aspects of Iberian leuciscids are limited. There is currently an information gap regarding effects of infectious diseases on these populations and their role as a possible conservation threat. Moreover, differences in susceptibility to particular agents, such as Aeromonas spp., by different species/populations is not clear. To understand potential differences in Aeromonas diversity and load, as well as in the prevalence and proportion of skin lesions, in fishes exposed to similar environmental conditions, an observational study was implemented. Using a set of 12 individuals belonging to two sympatric Iberian leuciscid species (Squalius pyrenaicus and Iberochondrostoma lusitanicum), the skin lesion score in each individual was analyzed. Furthermore, a bacterial collection of Aeromonas spp. isolated from each individual was created and isolates' load was quantified by plate counting, identified at species level using a multiplex-PCR assay and virulence profiles established using classical phenotypic methods. The similarity relationships of the isolates were evaluated using a RAPD analysis. The skin lesion score was significantly higher in S. pyrenaicus, while the Aeromonas spp. load did not differ between species. When analyzing Aeromonas species diversity between fishes, different patterns were observed. A predominance of A. hydrophila was detected in S. pyrenaicus individuals, while I. lusitanicum individuals displayed a more diverse structure. Similarly, the virulence index of isolates from S. pyrenaicus was higher, mostly due to the isolated Aeromonas species. Genomic typing clustered the isolates mainly by fish species and skin lesion score. Specific Aeromonas clusters were associated with higher virulence indexes. Current results suggest potential differences in susceptibility to Aeromonas spp. at the fish species/individual level, and constitute important knowledge for proper wildlife management through the signalization of at-risk fish populations and hierarchization of conservation measures., Competing Interests: The authors have declared that no competing interests exist.

Previous studies revealed high levels of antimicrobial resistance (AMR) in loggerhead sea turtles ( Caretta caretta ), describing this species as prime reservoir of antimicrobial-resistant bacteria. This study aimed to characterise, for the first time, the AMR and virulence profiles of Gram-negative bacteria isolated from 33 nesting loggerhead turtles of the island of Maio, Cape Verde. Cloacal, oral, and egg content swab samples ( n = 99) were collected and analysed using conventional bacteriological techniques. Shewanella putrefaciens , Morganella morganii, and Vibrio alginolyticus were isolated from the samples under study. The isolates obtained from this loggerhead subpopulation (North-East Atlantic) revealed lower levels of AMR, compared with the results of studies performed in other subpopulations (e.g., Mediterranean). However, the detection of resistance to carbapenems and multiple antimicrobial resistance indices higher than 0.20, raises concern about the potential association of these animals to points of high antimicrobial exposure. Furthermore, virulence phenotypic characterisation revealed that the isolates presented complex virulence profiles, including the ability to produce biofilms. Finally, due to their pathogenic potential, and considering the evidence of illegal consumption of turtle-related products on the island of Maio, the identified bacteria may represent a significant threat to public health.

Despite the fact that freshwater fish populations are experiencing severe declines worldwide, our knowledge on the interaction between endangered populations and pathogenic agents remains scarce. In this study, we investigated the prevalence and structure of Aeromonas communities isolated from the critically endangered Iberochondrostoma lusitanicum, a model species for threatened Iberian leuciscids, as well as health parameters in this species. Additionally, we evaluated the virulence profiles, antimicrobial resistance signatures and genomic relationships of the Aeromonas isolates. Lesion prevalence, extension and body condition were deeply affected by location and seasonality, with poorer performances in the dry season. Aeromonas composition shifted among seasons and was also different across river streams. The pathogenic potential of the isolates significantly increased during the dry season. Additionally, isolates displaying clinically relevant antimicrobial resistance phenotypes (carbapenem and fluroquinolone resistance) were detected. As it inhabits intermittent rivers, often reduced to disconnected pools during the summer, the dry season is a critical period for I. lusitanicum , with lower general health status and a higher potential of infection by Aeromonas spp. Habitat quality seems a determining factor on the sustainable development of this fish species. Also, these individuals act as reservoirs of important antimicrobial resistant bacteria with potential implications for public health.

In order to conduct an objective evaluation of potential ecological effects of grey seal predation on marine mammals, it is essential to establish a broad knowledge base helping in the thorough identification of such cases during post-mortem examination. The aim of this work is to report and discuss outcomes resulting from a retrospective evaluation of harbour (Phoca vitulina) and grey seal (Halichoerus grypus) stranding and necropsy data (n = 3274). In addition, the results are compared to a recent case of definite grey seal predation from Germany as well as reports from other countries. Carcasses potentially subjected to grey seal predation show severe lacerations with a circular pattern leaving a smooth, linear and cut-like wound margin. Large parts of skin and underlying tissue are detached from the body and loss of blubber is common. Occurrence frequencies of encountered lesions are presented and a list of parameters to be used for the assessment of similar cases as well as a complementary decision tree are suggested. With the proposed parameters, categories and tools, a baseline can be built in order to facilitate the standardised recognition of predation cases during post-mortem examinations of seals between groups working with populations across several geographic ranges.

As a follow-up on the data presented for seals, we herein report and discuss outcomes resulting from a retrospective evaluation of harbour porpoise stranding and necropsy data from Schleswig-Holstein, Germany (n = 4463) to enable an objective evaluation of potential ecological effects of grey seal predation on porpoises. Results are compared to a recent case of definite grey seal predation as well as to reports from other countries. Porpoise carcasses potentially subject to grey seal predation show severe lacerations, with large parts of skin and underlying tissue being detached from the body. Loss of blubber tissue is common. Based on the occurrence frequencies of encountered lesions, a list of parameters as well as a complementary decision tree are suggested to be used for future assessments. The results shown add to an increasingly standardised assessment protocol of suspected grey seal predation cases making respective results comparable between different areas and countries. The usage of a standardised protocol may increase the awareness of grey seal predation and the reporting of such cases. By this, differences in the predation and feeding patterns as well as the potential ecological relevance of this behaviour may be elucidated.

In the North Sea, white-beaked dolphins ( Lagenorhynchus albirostris ) occur regularly and are the second most common cetacean in the area, while their close relative, the Atlantic white-sided dolphin ( Lagenorhynchus acutus ), prefers the deeper waters of the northern North Sea and adjacent Atlantic Ocean. Though strandings of both species have occurred regularly in the past three decades, they have decreased in the southern North Sea during the last years. Studies describing necropsy findings in stranded Lagenorhynchus spp. are, to date, still scarce, while information gained through post-mortem examinations may reveal valuable information about underlying causes of this decline, including age structure and the reproduction status. Therefore, we retrospectively assessed and compared the necropsy results from fresh Lagenorhynchus spp. stranded along the southeastern North Sea between 1990 and 2019. A full necropsy was performed on 24 white-beaked dolphins and three Atlantic white-sided dolphins from the German and Dutch coast. Samples of selected organs were taken for histopathological, bacteriological, mycological, parasitological and virological examinations. The most common post-mortem findings were emaciation, gastritis and pneumonia. Gastritis and ulceration of the stomach was often associated with an anisakid nematode infection. Pneumonia was most likely caused by bacterial infections. Encephalitis was observed in three animals and morbillivirus antigen was detected immunohistochemically in one case. Although the animal also showed pneumonic lesions, virus antigen was only found in the brain. Parasitic infections mainly affected the gastro-intestinal tract. Lungworm infections were only detected in two cases and no associations with pathological alterations were observed. Stenurus spp. were identified in two of three cases of parasitic infections of the ears. Twelve of the 26 white-beaked dolphins stranded in Germany were found between 1993 and 1994, but there was no evidence of epizootic disease events or mass strandings during the monitored period., (Copyright © 2020 Schick, IJsseldijk, Grilo, Lakemeyer, Lehnert, Wohlsein, Ewers, Prenger-Berninghoff, Baumgärtner, Gröne, Kik and Siebert.)

Marine mammals are known to harbor Cryptosporidium spp. and Giardia spp., especially species or genotypes commonly associated with humans. In animals of the North and Baltic Seas, this information is missing. In this study, fecal samples ( n = 97) from harbor porpoises ( Phocoena phocoena), harbor seals ( Phoca vitulina), and grey seals ( Phocoena phocoena) present in German waters were examined via microscopic examination (by using a modified Ziehl-Neelsen technique [MZN]) to estimate the prevalence of these parasites. Additionally, intestinal tissue samples ( n = 1,049) from specimens of 10 marine mammal species were submitted for histopathologic examination (HP). A low prevalence was detected (2.1 and 1.3%, for MZN and HP, respectively), associated with Cryptosporidium spp. Giardia spp. was not observed. Current results suggest a low prevalence of these parasites in marine mammals present in Germany. However, methods with higher sensitivity, such as molecular methods, are crucial to confirm the prevalence, establish origin routes, and determine epidemiologic factors associated with the low prevalence observed.

Iron overload has been described in various wild species. The majority of cases involve captive animals, often associated with increased dietary iron uptake. Here a case of idiopathic iron overload in a female adult harbor seal under human care is presented. The animal displayed a progressive anorexia, apathy, and increased serum iron levels. Radiographs showed radiopaque foreign bodies in the stomach. The seal died during an elective laparotomy. Twenty-five coins and two metal rings were removed from the stomach. Histopathologic examination revealed iron storage without cellular damage in liver, spleen, kidney, and pulmonary and mesenteric lymph nodes. Atomic absorption spectrophotometry analysis for iron revealed values thirty times above the reference ranges in spleen and liver; however, the coins only contain minor levels (parts per million) of iron. The etiology of the iron overload in this animal remains unclear. A multifactorial process cannot be excluded.

We studied the etiology of encephalitis in a fin whale (Balaenoptera physalus) that stranded in 2016 on the coast of Denmark. Dolphin morbillivirus (DMV) was detected in the brain and other organs. Phylogenetics showed close relation to DMV isolated from a striped dolphin (Stenella coeruleoalba) from Spain in 2012.

Carcasses of wild animals are often visited by different scavengers. However, determining which scavenger caused certain types of bite marks is particularly difficult and knowledge thereof is lacking. Therefore, a loop-mediated isothermal amplification (LAMP) assay (target sequence cytochrome b) was developed to detect red fox DNA in carcasses of harbour porpoises. The MSwab™ method for direct testing without prior DNA isolation was validated. As a detection device, the portable real-time fluorometer Genie® II was used, which yields rapid results and can be used in field studies without huge laboratory equipment. In addition to in vitro evaluation and validation, a stranded and scavenged harbour porpoise carcass was successfully examined for red fox DNA residues. The developed LAMP method is a valuable diagnostic tool for confirming presumable red fox bite wounds in harbour porpoises without further DNA isolation steps.

Anthropogenic landscape changes contributed to the reduction of availability of habitats to wild animals. Hence, the presence of wild terrestrial carnivores in urban and peri-urban sites has increased considerably over the years implying an increased risk of interspecies spillover of infectious diseases and the transmission of zoonoses. The present study provides a detailed characterisation of the health status of the red fox (Vulpes vulpes), stone marten (Martes foina) and raccoon dog (Nyctereutes procyonoides) in their natural rural and peri-urban habitats in Schleswig-Holstein, Germany between November 2013 and January 2016 with focus on zoonoses and infectious diseases that are potentially threatening to other wildlife or domestic animal species. 79 red foxes, 17 stone martens and 10 raccoon dogs were collected from traps or hunts. In order to detect morphological changes and potential infectious diseases, necropsy and pathohistological work-up was performed. Additionally, in selected animals immunohistochemistry (influenza A virus, parvovirus, feline leukemia virus, Borna disease virus, tick-borne encephalitis, canine adenovirus, Neospora caninum, Toxoplasma gondii and Listeria monocytogenes), next-generation sequencing, polymerase chain reaction (fox circovirus) and serum-neutralisation analysis (canine distemper virus) were performed. Furthermore, all animals were screened for fox rabies virus (immunofluorescence), canine distemper virus (immunohistochemistry) and Aujeszky's disease (virus cultivation). The most important findings included encephalitis (n = 16) and pneumonia (n = 20). None of the investigations revealed a specific cause for the observed morphological alterations except for one animal with an elevated serum titer of 1:160 for canine distemper. Animals displayed macroscopically and/or histopathologically detectable infections with parasites, including Taenia sp., Toxocara sp. and Alaria alata. In summary, wildlife predators carry zoonotic parasitic disease and suffer from inflammatory diseases of yet unknown etiology, possibly bearing infectious potential for other animal species and humans. This study highlights the value of monitoring terrestrial wildlife following the "One Health" notion, to estimate the incidence and the possible spread of zoonotic pathogens and to avoid animal to animal spillover as well as transmission to humans.

Dextrans (α-d-glucans) extracted from Leuconostoc mesenteroides, with molecular weights (MW) of 10 (D10), 40 (D40) and 147 (D147) kDa, were evaluated as antioxidant, anticoagulant and immunomodulatory drugs for the first time. None presented anticoagulant activity. As for the antioxidant and immunomodulatory tests, a specific test showed an increase in the dextran activity that was proportional to the increase in molecular weight. In a different assay, however, activity decreased or showed no correlation to the MW. As an example, the reducing power assay showed that D147 was twice as potent as other dextrans. On the other hand, all three samples showed similar activity (50%) when it came to scavenging the OH radical, whereas only the D10 sample showed sharp activity (50%) when it came to scavenging the superoxide ion. D40 was the single dextran that presented with immunomodulatory features since it stimulated the proliferation (~50%) of murine macrophages (RAW 264.7) and decreased the release of nitric oxide (~40%) by the cells, both in the absence and presence of lipopolysaccharides (LPS). In addition, D40 showed a greater scavenging activity (50%) for the hydrogen peroxide, which caused it to also be the more potent dextran when it came to inhibiting lipid peroxidation (70%). These points toward dextrans with a 40 kDa weight as being ideal for antioxidant and immunomodulatory use. However, future studies with the D40 and other similarly 40 kDa dextrans are underway to confirm this hypothesis.

Avian malaria is a mosquito-borne disease caused by protozoans of the genus Plasmodium, and it is considered one of the most important causes of morbidity and mortality in captive penguins, both in zoological gardens and rehabilitation centres. Penguins are known to be highly susceptible to this disease, and outbreaks have been associated with mortality as high as 50-80% of affected captive populations within a few weeks. The disease has also been reported in wild penguin populations, however, its impacts on the health and fitness of penguins in the wild is not clear. This review provides an overview of the aetiology, life cycle and epidemiology of avian malaria, and provides details on the strategies that can be employed for the diagnostic, treatment and prevention of this disease in captive penguins, discussing possible directions for future research.

The molecular karyotype of Perkinsus olseni, a pathogenic protist that infects the clam Ruditapes decussatus, comprises nine chromosomes, ranging in size from 0.15 Mb to 6.5 Mb, representing a haploid genome of about 28 Mb. In order to establish chromosome specific markers, PCR-amplified DNA sequences belonging to five conserved genes (18S rRNA, actin type I, hsp90, β-tubulin and calmodulin) were hybridised to chromosomal bands separated by pulsed-field gel electrophoresis. Three of those probes (actin type I, hsp90 and calmodulin) hybridised to only one chromosome and the remaining two (18S rRNA and β-tubulin) hybridised to two chromosomes. In the first place, the hybridisation pattern obtained serves to dispel any doubt about the nuclear location of the smallest chromosome observed in the molecular karyotype of Perkinsus olseni. Additionally, it will be a reference for further analysis of karyotype polymorphisms in the genus Perkinsus., (Copyright © 2011 Elsevier GmbH. All rights reserved.)

A previously unrecognised fish-infecting microsporidia (Loma psittaca n. sp.), found adherent to the intestinal mucosa of the freshwater puffer fish Colomesus psittacus (Teleostei, Tetraodontidae) from lower Amazon River, was described based on light and transmission electron microscope and phylogenetic analysis. The whitish xenoma was completely filled by numerous spores, including several developmental stages of the parasite. In all of these stages, the nuclei were monokaryotic. The merogonial plasmodium divided by binary fission and the sporont gave rise to disporoblastic ovoid spores measuring 4.2 +/- 0.4 x 2.8 +/- 0.4 microm. In mature spores, the polar filament was arranged in 10-11 (rarely 12) coils in one row in turn of posterior vacuole. The polaroplast had two distinct regions around the manubrium. The polyribosomes were organised in coiled tapes. The small subunit rRNA gene was sequenced and maximum parsimony analysis placed the microsporidian described here in the clade that includes the genera Ichthyosporidium, Loma and Pseudoloma. Based on differences from previously described microsporidians, such as ultrastructural characteristics of the xenoma, developmental stages including the spore and phylogenetic analysis supported the recognition of a new species, herein named L. psittaca n. sp.

A fish-infecting Microsporidia Potaspora morhaphis n. gen., n. sp. found adherent to the wall of the coelomic cavity of the freshwater fish, Potamorhaphis guianensis, from lower Amazon River is described, based on light microscope and ultrastructural characteristics. This microsporidian forms whitish xenomas distinguished by the numerous filiform and anastomosed microvilli. The xenoma was completely filled by several developmental stages. In all of these stages, the nuclei are monokaryotic and develop in direct contact with host cell cytoplasm. The merogonial plasmodium divides by binary fission and the disporoblastic pyriform spores of sporont origin measure 2.8+/-0.3 x 1.5+/-0.2 microm. In mature spores the polar filament was arranged into 9-10 coils in 2 layers. The polaroplast had 2 distinct regions around the manubrium and an electron-dense globule was observed. The small subunit, intergenic space and partial large subunit rRNA gene were sequenced and maximum parsimony analysis placed the microsporidian described here in the clade that includes the genera Kabatana, Microgemma, Spraguea and Tetramicra. The ultrastructural morphology of the xenoma, and the developmental stages including the spores of this microsporidian parasite, as well as the phylogenetic analysis, suggest the erection of a new genus and species.

Perkinsus atlanticus is a pathogenic protist that infects the clam Ruditapes decussatus. The recent proposal for the inclusion of the genus Perkinsus in a new phylum, Perkinsozoa, in the infra-kingdom Alveolata, gave rise to controversies whether this genus should form a phylum on its own. Molecular analysis of some conserved nuclear genes shows a closer proximity of the genus Perkinsus to the dinoflagellates than to the apicomplexans. Studies on extranuclear genomes, however, could also be very helpful for a more precise definition of those phyla. In Perkinsozoa, there have been until now no reports about the isolation of mitochondria as well as no conclusive results about the presence of any plastids, therefore a comparison with the data already obtained in Apicomplexa and Dinoflagellata has not yet been possible. In this work, we identify a plastid in Perkinsus atlanticus, using ultrastructural techniques and inhibition growth tests. It will be important to analyze the plastid genome at a molecular level, in order to confirm if the plastid in Perkinsus is more similar to those of Dinoflagellata or Apicomplexa. Such information will doubtless contribute to a more precise determination of the phylogenetic position of the genus Perkinsus.

In order to assess the role of collagens I and IV during the angiogenic process associated with bleomycin-induced pulmonary fibrosis in rat, in situ hybridization and immunocytochemical studies were carried out. An increased expression of collagen IV was observed before an enhanced expression of collagen I after intratracheal instillation of bleomycin. Deposits of both collagen types were detected on the 21st day after treatment with bleomycin, surrounding the new blood vessels formed during the fibrotic process. At this time, the presence of new lymphatic vessels was associated uniquely with deposition of collagen I. These observations lead us to conclude that, at least during pulmonary fibrosis, lymphangiogenesis takes place after blood angiogenesis.

The effect of edeine and the mutation edr-2 to edeine resistance on genetic recombination in Neurospora crassa was investigated. For this purpose crosses between pairs of edeine sensitive and edeine resistant strains respectively were set up without or in the presence of the drug (0-750 microg/ml). The genetic markers ylo-1, ad-1, pan-2 (B3 and B5) and tryp-2, all on linkage group VI, were used for scoring recombinants. These were ad+, tryp+ (intergenic recombination) and pan+ (interallelic recombination). Frequencies of about 6-7% for intergenic and of about 0.4% for interallelic recombination were found in crosses between eds strains and ed(r) strains respectively, if edeine was absent. However, crosses in the presence of edeine gave higher frequencies of both intergenic and interallelic recombination (about 12% intergenic and 1% interallelic with 180 to 200 microg ed/ml). The pan+ prototrophs (interallelic recombinants) obtained in the different crosses were tested for distribution of outside markers. The data thus obtained revealed that under the effect of both the mutation to edeine resistance and edeine itself the relative number of noncrossover (gene conversion) recombinants decreases in favour of crossover recombinants, and the relative number of double crossover recombinants (events outside the pan locus) decreases in favour of single crossover recombinants. It is concluded that a) edeine and the mutation ed(r)-2 to edeine resistance affect recombination via related pathways, and b) noncrossover and crossover recombinants are caused by different molecular mechanisms, in agreement with the work of other authors.