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Ticks are vectors of important pathogens of human and animals. Therefore, their microbial carriage capacity is constantly being investigated. The aim of this study was to characterize the diversity of domestic animal pathogens in ticks collected from vegetation and the ground, from different parts of Israel. Non-engorged questing adult ticks were collected from 13 localities. A total of 1196 ticks in 131 pools-83 pools of Rhipicephalus turanicus and 48 of Rhipicephalus sanguineus (with two to ten ticks per pool)-were included in this study. In addition, 13 single free-roaming Hyalomma spp. ticks were collected. Screening by molecular techniques revealed the presence of Ehrlichia canis, Anaplasma platys, Anaplasma bovis and Babesia canis vogeli DNA in R. turanicus ticks. E. canis, A. bovis, B. canis vogeli and Candidatus Midichloria mitochondrii DNA sequences were detected in R. sanguineus ticks. Candidatus Midichloria mitochondrii DNA was also detected in Hyalomma spp. ticks. Neither Hepatozoon spp. nor Bartonella spp. DNA was detected in any of the ticks examined. This study describes the first detection of E. canis in the tick R. turanicus, which may serve as a vector of this canine pathogen; E. canis was the most common pathogen detected in the collected questing ticks. It also describes the first detection of A. bovis and Candidatus Midichloria mitochondrii in Israel. To the best of the author's knowledge, this is the first report describing the detection of DNA of the latter two pathogens in R. sanguineus, and of A. bovis in R. turanicus. [ABSTRACT FROM AUTHOR]

The classic epidemiological triangle model of host-environment-pathogen is recently being reshaped into a tetrahedron, with the growing understanding of the importance of the microbiome in this array. The gills, being a gateway into the fish body, bearing an important role in fish homeostasis, host a complex microbiome that reflects the ambient water, while also showing resemblance to gut microbiome. Next-generation sequencing (NGS) and improvements in data analysis tools enable researchers to gather and analyse a lot more data than ever before, take a closer, more detailed look at microbiota, and gain a much better understanding of the biological processes at work in these complex relations. Here, 16S rRNA amplicons of bacterial DNA extracted from the gills of 36 asymptomatic specimens of three wild fish species from the South China Sea (Nemipterus japonicus, Alepes djebaba, and Saurida tumbil) were sequenced using NGS. Data analyses revealed the presence of 20 potentially pathogenic species, including several zoonotic agents. Gill microbiota exhibited host species-specificity, and expressed a significant difference between demersal and pelagic-amphidromous fish. It is suggested that this method be more widely implemented, in order to gain more insight on ocean ecosystems' health status, as well as fish stocks of commercial importance., (© 2024 The Author(s). Journal of Fish Diseases published by John Wiley & Sons Ltd.)

Objective: The Blackchin Guitarfish Glaucostegus cemiculus is endemic to the Mediterranean Sea and is critically endangered, but relevant routine laboratory data are unavailable. Our objectives were to determine the packed cell volume (PCV), comprehensive serum chemistry analytes, and serum total thyroxine (sTT4) concentration; compare serum albumin and serum globulin concentrations as measured by two different methods; and describe the blood cell morphology of healthy, free-ranging Blackchin Guitarfish., Methods: Wild Blackchin Guitarfish were captured using a seine net. Blood samples for serum chemistry and hematological analyses were obtained and measured using routine laboratory methods. The fish were tagged and released., Result: This study included 43 Blackchin Guitarfish (17 males and 26 females) that were younger than 6 months as estimated based on total length and body weight. The median PCV (n = 23) was 22% (minimum-maximum [min-max] = 15-25%). Median sTT4 (n = 10) measured by chemiluminescence immunoassay was 7.86 nmol/L (min-max = 7.52-9.57 nmol/L). The study included a comprehensive, 25-analyte serum chemistry analysis (e.g., serum iron and unbound and total iron-binding capacity) and a morphological description of all blood cells. Serum electrophoresis (SEP; n = 13) yielded a consistent serum albumin-migrating protein fraction and four globulin fractions. Serum electrophoretograms corroborating these results are presented., Conclusion: In Blackchin Guitarfish, the serum albumin-migrating fraction measured by SEP combined with serum total protein concentration yields a much higher albumin concentration compared to that measured by bromocresol green spectrophotometry. The true identity of this albumin-migrating fraction remains to be identified. The analytes' calculated 2.5-97.5% interpercentile intervals should be considered as reference intervals applying to Blackchin Guitarfish of similar age but should be applied cautiously to adult fish., (© 2024 American Fisheries Society.)

The Eastern Mediterranean Sea (EMS) exhibits high temperature and salinity, low levels of biologic production and is considered oligotrophic. Nonetheless, it is also a hotspot of biodiversity, with several important endangered flagship species, including several species of sea turtles. These turtles serve as bioindicators for the health of their ecologic systems, due to changes in diet, habitat and migration patterns that characterize different stages in their lives. This study covered 100 blood samples taken between 2008 and 2019 from 72 green sea turtles (Chelonia mydas) tested for 67 elements, some of which carry toxic potential. The turtles were treated at the Israeli Sea Turtle Rescue Center (ISTRC) after being rescued from sea, exhibiting a variety of health conditions and Injuries. The data were compared to similar studies worldwide and serve as a basis for monitoring the health status of the green sea turtles' EMS populations. The results of all animals presented noticeably high levels of sulfur - an order of magnitude higher than sea turtles from other locations around the world. This paper discusses the possible origins of this element, as well as its potential effects, while raising the question regarding the ability of these sea turtles to endure such sulfur levels., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

In September 2020, a male common dolphin (Delphinus delphis) was found dead on a beach near Bat-Yam, Israel. A small, raised, well circumscribed penile lesion (i.e., mass) was identified and removed for histology and molecular characterizations. By histology, the penile mass presented focal keratinization of the squamous epithelium and a mild ballooning of acanthocytes in lower epithelium levels, as well as features compatible with viral plaques, and tested positive for a gammaherpesvirus through molecular characterization analyses. Tissue samples from the lungs, liver, and spleen, however, tested negative for herpesvirus infection. The gammaherpesvirus detected herein is similar to other isolates found in several areas worldwide in different cetacean species. This is the first reported case of gammaherpesvirus infection in dolphins from the eastern Mediterranean Sea, indicative of the need for long-term assessments to create viral infections databases in cetaceans, especially in a climate change context, which is likely to intensify infectious disease outbreaks in marine mammals in the future., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Among the numerous pathogenic nontuberculous mycobacteria (NTM), which may cause disease in both poikilothermic and homoeothermic organisms, members of the unique clade Mycobacterium ulcerans/Mycobacterium marinum (MuMC) may cause disease in both fish and humans. Here, we describe the emergence of Mycobacterium pseudoshottsii, one of the four MuMC members, in Israel. For many years, M. marinum was the dominant NTM that was diagnosed in Israel as a fish pathogen. To the best of our knowledge, this is the first isolation and genomic characterization of M. pseudoshottsii infecting edible fish from two different fish species farmed in offshore sea cages in the eastern Mediterranean as well as in a recirculating aquaculture system in Israel. We compared the M. pseudoshottsii whole-genome sequences to all available genomic sequences of MuMC in free, publicly accessible databases. IMPORTANCE Mycobacterium pseudoshottsii was first detected in 1997 in the USA, infecting wild striped bass (Morone saxatilis). Since then, several reports from different countries worldwide have shown its capacity to become established in new regions as well as its pathogenicity to saltwater and euryhaline finfish of different genera. Our phylogenetic analysis revealed that the Mycobacterium ulcerans/Mycobacterium marinum clade (MuMC) is divided into two main branches: one that includes M. marinum and M. pseudoshottsii , and the second, which includes other M. marinum isolates as well as two isolates of M. shottsii. Our results reinforce the proposition that the geographical distribution of M. pseudoshottsii is much more extensive than is commonly believed. The emergence of M. pseudoshottsii in different parts of the world and its pathogenic traits that affect finfish of different genera may be a cause for concern among fish farmers, researchers, and environmental organizations., Competing Interests: The authors declare no conflict of interest.

Freshwater and marine ecosystems are a suitable habitat for parasitic nematodes of the genus Contracaecum (family: Anisakidae) to complete their complex life cycle. Several fish species of the Sea of Galilee (Lake Kinneret) were reported in 1964 as second intermediate/paratenic hosts of Contracaecum spp. larvae. The lack of taxonomically relevant morphological features of these larvae hindered their proper identification. Here we report the results of a 1-year survey conducted in 2021, 57 years after the first (and only) such survey. We analyzed 352 specimens from 10 fish species (native and non-native) of the Sea of Galilee (Israel) ichthyofauna. We compared our results with those of the first parasitological survey conducted by Paperna in 1964; the overall prevalence of nematodes referable to Contracaecum larvae was 16.8% and 0.85% in 1964 and in 2021, respectively. Different from the first survey that identified Contracaecum larvae morphologically, we used both morphological and molecular tools. Two wild native cyprinids-Jordan himri ( Carasobarbus canis ) and Jordan barbel ( Luciobarbus longiceps )-were infected (a single specimen each) with Contracaecum quadripapillatum larvae in their abdominal cavity. A single specimen of blue tilapia ( Oreochromis aureus ) was infected with two larvae of Contracaecum multipapillatum E, localized in the pericardial cavity. The findings of our study, which is part of a large project focused on Contracaecum spp. infecting both piscivorous birds and fish collected in Israel, advance our knowledge about the distribution and host range of this potentially zoonotic parasite in fishery products of the Sea of Galilee., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Shark assessments in the Mediterranean Sea are still scarce, and serum chemistry and haematological data have yet to be reported for wild dusky ( Carcharhinus obscurus ) or sandbar ( Carcharhinus plumbeus ) shark populations in the Mediterranean Sea. Herein, blood samples were obtained from adult dusky ( n  = 23) and sandbar ( n  = 14) sharks from an aggregation site near the Hadera power and desalination plants in Israel in the winters of 2016-20. Several serum chemistry analytes were characterized with relation to stress, body size and environmental conditions. Glucose concentrations were higher, while total cholesterol concentrations were lower in dusky sharks than in sandbar sharks, potentially due to distinct metabolic pathways utilized during the capture-related activity by both species. However, differences in sex and size are noted and should be considered. The blood cell morphology of both species was consistent with previous findings for sandbar sharks. Atypical monocytes were noted in one dusky shark. Preliminary and exploratory reference intervals for female dusky sharks were calculated for glucose, triglycerides, total cholesterol, total protein and creatine kinase. These data must be viewed with caution due to the potential influence of capture-related stress on analyte concentrations and activities and the fact that only females were employed in the calculations. Moreover, the sampling site is adjacent to coastal power and desalination plants, which may significantly affect shark physiology. Although limited, this novel database on dusky and sandbar shark serum chemistry and haematology aspects is essential as a first attempt to obtain data on these species in the eastern Mediterranean Sea and for future conservation and long-term biomonitoring efforts., (© The Author(s) 2023. Published by Oxford University Press and the Society for Experimental Biology.)

Sharks, as apex predators, play an essential ecological role in shaping the marine food web and maintaining healthy and balanced marine ecosystems. Sharks are sensitive to environmental changes and anthropogenic pressure and demonstrate a clear and rapid response. This designates them a "keystone" or "sentinel" group that may describe the structure and function of the ecosystem. As a meta-organism, sharks offer selective niches (organs) for microorganisms that can provide benefits for their hosts. However, changes in the microbiota (due to physiological or environmental changes) can turn the symbiosis into a dysbiosis and may affect the physiology, immunity and ecology of the host. Although the importance of sharks within the ecosystem is well known, relatively few studies have focused on the microbiome aspect, especially with long-term sampling. Our study was conducted at a site of coastal development in Israel where a mixed-species shark aggregation (November-May) is observed. The aggregation includes two shark species, the dusky ( Carcharhinus obscurus ) and sandbar ( Carcharhinus plumbeus ) which segregate by sex (females and males, respectively). In order to characterize the bacterial profile and examine the physiological and ecological aspects, microbiome samples were collected from different organs (gills, skin, and cloaca) from both shark species over 3 years (sampling seasons: 2019, 2020, and 2021). The bacterial composition was significantly different between the shark individuals and the surrounding seawater and between the shark species. Additionally, differences were apparent between all the organs and the seawater, and between the skin and gills. The most dominant groups for both shark species were Flavobacteriaceae, Moraxellaceae, and Rhodobacteraceae. However, specific microbial biomarkers were also identified for each shark. An unexpected difference in the microbiome profile and diversity between the 2019-2020 and 2021 sampling seasons, revealed an increase in the potential pathogen Streptococcus. The fluctuations in the relative abundance of Streptococcus between the months of the third sampling season were also reflected in the seawater. Our study provides initial information on shark microbiome in the Eastern Mediterranean Sea. In addition, we demonstrated that these methods were also able to describe environmental episodes and the microbiome is a robust measure for long-term ecological research., 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 © 2023 Bregman, Lalzar, Livne, Bigal, Zemah-Shamir, Morick, Tchernov, Scheinin and Meron.)

Along the Mediterranean coast of Israel, two near-shore dolphin species are prevalent; Tursiops truncatus (least concern, IUCN) and Delphinus delphis (endangered, IUCN). Ship-board surveys and sporadic sightings over the last two decades have shown that the two differ in distribution- T. truncatus is found along the entire coast and D. delphis only in the south. The environmental and anthropological factors affecting these species' spatial distribution and determining their habitat preferences in this area are largely unknown. This work is a first attempt at summarizing 20 years of observations and studying habitat preferences for both species, by use of Generalized Additive Models. T. truncatus was found to be present in all areas of the continental shelf where survey effort coverage was sufficient, with a high affinity towards bottom trawlers. Model results showed D. delphis distribution to be associated to (shallow) water depths, though the factors driving their limited latitudinal distribution currently remain unknown. It is evident that T. truncatus and D. delphis are present in segregated areas of the Israeli continental shelf and T. truncatus currently sustains a delicate balance with continuously shifting human activities, while the drivers of D . delphis distribution are more specified, yet still not fully understood.

Photobacterium damselae subspecies damselae, an abundant, generalist marine pathogen, has been reported in various cetaceans worldwide. We report a bottlenose dolphin in the eastern Mediterranean Sea that was found stranded and dead. The dolphin had a severe case of chronic suppurative pneumonia and splenic lymphoid depletion caused by this pathogen.

Elasmobranchs have a very distinct metabolism, and many aspects related to the energetic dynamics of these animals remain poorly investigated. The reproductive period is particularly vulnerable for viviparous species, as part of the energy reserves of the parental biomass is reallocated for gamete production and embryo development. In this context, this study aimed to characterize parental metabolite provisioning to the offspring (both sperm and developing embryos) of the Brazilian Guitarfish, Pseudobatos horkelii , through glucose, β-hydroxybutyrate, triglycerides, and total cholesterol determinations in the uterine liquid (UL) and serum of pregnant females and in the seminal fluid (SF) and serum of males during the copulation period. No significant difference was observed for the analyzed markers between the UL and SF. Except for triglycerides, higher in female serum samples, all other energy markers were present at similar concentrations in the serum of both females and males. When comparing female UL and serum, significant differences were observed for triglycerides and total cholesterol. No differences were observed between SF and serum in males. The results indicate that all markers are being made available to offspring, possibly complementary to the yolk in the case of maternal liquid, and as an additional source for sperm mobilization required during egg fertilization in the case of the paternal fluid. Correlations between the markers in the parental matrices were also noted, compatible with the metabolic pathways activated during energy mobilization in vertebrates. Moreover, distinct marker predominance patterns were also noted for both UL and SF. Energy mobilization characterization directed to offspring through parental fluids aids in unraveling metabolic dynamics during the reproduction stage while also providing support for stress physiology studies to evaluate the indirect effects of parental allostatic overload in both sperm and developing embryos. Finally, energy mobilization assessments of parental fluids may also help elucidate how internal fertilization and viviparity evolved in this very distinct taxonomic group., 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 Wosnick, Leite, Giareta, Morick and Hauser-Davis.)

Nematodes belonging to the genus Contracaecum (family: Anisakidae) are heteroxenous parasites with a complex life cycle. Contracaecum larvae infecting farmed fish and fishery products are economically important causing market rejection in massive infection and may have zoonotic potential. In Israel, Contracaecum larvae have been described morphologically in several fish species; however, none of these descriptions were supported by molecular tools. In 2019-2020, hybrid tilapia ( Oreochromis aureus x Oreochromis niloticus ) and red drum ( Sciaenops ocellatus ), farmed in polyculture were found to be heavily infected with nematodes referable to Contracaecum larvae. Prevalence of infection in hybrid tilapia and red drum was 53.8% and 40.9%, respectively. A combined (morphological and molecular) approach revealed that both infected fish species were parasitized by the same species of Contracaecum , although larvae in hybrid tilapia were localized in the pericardial cavity whereas in red drum, they were observed in the abdominal cavity. Genetic analysis of internal transcribed spacer rDNA and cox 2 mtDNA showed high similarity to unidentified Contracaecum larvae detected in several fish species in Ethiopia, Egypt and Kenya. In this study, molecular and morphological analyses place the possible new species in the C. multipapillatum complex and was provisionally named C. multipapillatum E. Further analyses combining morphological and molecular approaches are required on adult specimens collected from piscivorous birds living in the same area to support the identification of a potentially new species., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 Published by Elsevier Inc. on behalf of International Association of Food and Waterborne Parasitology.)

Seafood is capable of bioaccumulating heavy metals (HM), making it a potentially major dietary source of HM for humans. Presently, little data exists on seafood from the eastern-most boundary of the Mediterranean Sea. This study aims to provide exposure insight of the Israeli population to HM through the consumption of locally caught seafood by assessing the levels of arsenic, mercury, cadmium, and lead in raw tissues of seafood. A wide survey of local fisheries was conducted providing 296 samples from 11 different species, including seven fish, two crustacean, and two cephalopod species. Total arsenic, cadmium, and lead were analyzed by graphite-furnace atomic absorption. Total mercury was measured by cold-vapor mercury analyzer. Arsenic speciation was performed by anion chromatography-inductively coupled plasma sector field mass spectrometry. Results suggested that the total arsenic concentrations were significantly higher in crustaceans and cephalopods than fish. Arsenic speciation revealed two samples that exceed 1 mg/kg of inorganic arsenic, whereas methylated arsenic was below the detection limit. Elevated mercury levels were detected in the commercial benthic species Mullus barbatus (red mullet), cadmium was detected in one-third of the samples, and lead detected in eight samples. Comparing the results to health guidelines, 99.4% of seafood tested in this study abide with acceptable levels of heavy metals in seafood, as defined by both Israeli and European Union guidelines., (© 2021 Institute of Food Technologists®.)

Physiological adaptations have evolved to help sharks face rapid periods of feast. Tiger sharks are generalist apex predators that rely on a high-lipid/protein diet. To achieve a satisfactory nutritional condition, proper lipid absorption and hepatic storage are needed. Bile secretion in sharks is low and sporadic but increases during short periods of fasting. The present study describes a physiological impairment caused by bile accumulation in juvenile tiger sharks, possibly due to prolonged fasting. These evidences suggest that, even though sharks have adaptations that prevent them from dying from starvation, alarming physiological alterations might occur. Future studies are needed to assess how such a condition can affect wild populations, as well as possible sublethal consequences that could impact their long-term survival.

Mycobacteriosis is a chronic bacterial disease reported in aquatic and terrestrial animals, including humans. The disease affects a wide range of cultured and wild organisms worldwide. Mycobacteriosis is well-known in aquatic vertebrates (e.g., finfish, marine mammals), while in the last few years, reports of its presence in aquatic invertebrates have been on the rise, for both freshwater and marine species. The number of cases is likely to increase as a result of increased awareness, surveillance and availability of diagnostic methods. Domestication of wild aquatic species and the intensification of modern aquaculture are also leading to an increase in the number of reported cases. Moreover, climate changes are affecting fresh and marine aquatic ecosystems. The increasing reports of mycobacteriosis in aquatic invertebrates may also be influenced by global climate warming, which could contribute to the microbes' development and survival rates, pathogen transmission and host susceptibility. Several species of the genus Mycobacterium have been diagnosed in aquatic invertebrates; a few of them are significant due to their wide host spectrum, economic impact in aquaculture, and zoonotic potential. The impact of mycobacteriosis in aquatic invertebrates is probably underestimated, and there is currently no effective treatment other than facility disinfection. In this review, we provide an overview of the diversity of mycobacterial infections reported in molluscs, crustaceans, cnidarians, echinoderms and sponges. We highlight important issues relating to its pathological manifestation, diagnosis and zoonotic considerations.

In contrast to numerous documented pathogens and infectious diseases of aquaculture, there is a lack of baseline data and information regarding pathogenic agents' prevalence in wild marine fish populations. This study focused on two common fish pathogenic microorganisms, namely Mycobacterium species and Vibrio species, both of which are known to be major causes of fish loss, occasionally to the extent of being a limiting factor in fish production. Both microorganisms are known as zoonotic agents. In total, 210 wild marine indigenous and Lessepsian fish from four different species from the eastern Mediterranean Sea were sampled and tested for Vibrio species and Mycobacterium species during a two-year period (2016-2017). Using PCR with 16S rRNA primers, we detected different strain variations of Mycobacterium species and Vibrio species and, based on the sequencing results, the overall prevalence for Vibrio species in wild fish in 2016 was significantly higher compared to 2017. No significant difference was detected for Mycobacterium species prevalence in wild fish between 2016 and 2017. In addition, 72 gilthead seabream (Sparus aurata) from an Israeli offshore marine farm were also examined during the two-year period (2017-2018). The results suggest that Mycobacterium species prevalence was significantly higher in 2018, while in 2017 there was no positive results for Mycobacterium species. In addition, there was no significant difference between both years in regard to the prevalence of Vibrio species for maricultured fish. These results highlight the necessity of continuous molecular monitoring in order to evaluate the prevalence of pathogenic microorganisms in both wild and cultured fish populations., Competing Interests: The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

This study is an initial description and discussion of the kidney and liver microbial communities of five common fish species sampled from four sites along the Eastern Mediterranean Sea shoreline. The goals of the present study were to establish a baseline dataset of microbial communities associated with the tissues of wild marine fish, in order to examine species-specific microbial characteristics and to screen for candidate pathogens. This issue is especially relevant due to the development of mariculture farms and the possible transmission of pathogens from wild to farmed fish and vice versa. Although fish were apparently healthy, 16S rRNA NGS screening identified three potential fish bacterial pathogens: Photobacterium damselae, Vibrio harveyi and Streptococcus iniae. Based on the distribution patterns and relative abundance, 16 samples were classified as potential pathogenic bacteria-infected samples (PPBIS). Hence, PPBIS prevalence was significantly higher in kidneys than in liver samples and variation was found between the fish species. Significant differences were observed between fish species, organs and sites, indicating the importance of the environmental conditions on the fish microbiome. We applied a consistent sampling and analytical method for monitoring in long-term surveys which may be incorporated within other marine fish pathogens surveys around the world., (© 2020 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.)

Viruses are among the most abundant and diverse biological components in the marine environment. In finfish, viruses are key drivers of host diversity and population dynamics, and therefore, their effect on the marine environment is far-reaching. Viral encephalopathy and retinopathy (VER) is a disease caused by the marine nervous necrosis virus (NNV), which is recognized as one of the main infectious threats for marine aquaculture worldwide. For over 140 years, the Suez Canal has acted as a conduit for the invasion of Red Sea marine species into the Mediterranean Sea. In 2016-2017, we evaluated the prevalence of NNV in two indigenous Mediterranean species, the round sardinella ( Sardinella aurita ) and the white steenbras ( Lithognathus mormyrus ) versus two Lessepsian species, the Randall's threadfin bream ( Nemipterus randalli ) and the Lessepsian lizardfish ( Saurida lessepsianus ). A molecular method was used to detect NNV in all four fish species tested. In N. randalli , a relatively newly established invasive species in the Mediterranean Sea, the prevalence was significantly higher than in both indigenous species. In S. lessepsianus , prevalence varied considerably between years. While the factors that influence the effective establishment of invasive species are poorly understood, we suggest that the susceptibility of a given invasive fish species to locally acquired viral pathogens such as NVV may be important, in terms of both its successful establishment in its newly adopted environment and its role as a reservoir 'host' in the new area.

Streptococcus agalactiae is one of the most important fish pathogenic bacteria as it is responsible for epizootic mortalities in both wild and farmed species. S. agalactiae is also known as a zoonotic agent. In July 2018, a stranded wild sandbar shark ( Carcharhinus plumbeus ), one of the most common shark species in the Mediterranean Sea, was found moribund on the seashore next to Netanya, Israel, and died a few hours later. A post-mortem examination, histopathology, classical bacteriology and advanced molecular techniques revealed a bacterial infection caused by S. agalactiae , type Ia-ST7. Available sequences publicly accessible databases and phylogenetic analysis suggest that the S. agalactiae isolated in this case is closely related to fish and human isolates. To the best of our knowledge, this is the first description of a fatal streptococcosis in sandbar sharks., Competing Interests: The authors declare no conflict of interest.

Toxoplasma gondii has been described in several marine mammals around the world including numerous species of cetaceans, yet infection and transmission mechanisms in the marine environment are not clearly defined. The Israel Marine Mammal Research and Assistance Center has been collating a database of all marine mammal stranding events along the country's national coastlines since 1993. In this study, we describe the molecular detection and characterisation of T. gondii in three common bottlenose dolphins (Tursiops truncatus) including one case of coinfection with herpesvirus. The animals were found stranded on the Mediterranean coast of Israel in May and November 2013. In one of the three cases, the dolphin was found alive and admitted to intensive care. To our knowledge, this is the first report of T. gondii infection of marine mammals in the Eastern Mediterranean Sea. As this parasite acts as an indicator for marine pollution and marine mammal health, we believe these findings add important information regarding the state of the environment in this region., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The guanosine analog ribavirin is a broad-spectrum antiviral drug, mostly used in human clinical practice. It has in vitro and in vivo activity against a broad range of RNA and DNA viruses. Here, we report that treatment of zebrafish larvae with ribavirin prior to infection with nervous necrosis virus (NNV) significantly reduces the mortality caused by the virus during the first 10 days post-infection. The RNA genome of NNV harvested from ribavirin-treated infected larvae contains three synonymous and one single non-synonymous mutation, resulting in the replacement of a serine codon with a glycine codon in the RNA-dependent RNA polymerase gene. Adding increasing amounts of guanosine to ribavirin prior to larvae infection did not impede the antiviral activity. Ribavirin treatment of uninfected larvae reduces the basal level of IFNγ, but increases the level of IL-1β mRNA expression. Furthermore, infecting larvae with NNV following ribavirin treatment reduces the expression levels of IFNγ, IFN-I, Mx, and TNF-α genes, while the expression of IL-1β is increased. These results suggest that cytokine modulation plays an important role in the activity of ribavirin against NNV. Mortality of more than 40 species of teleost fish, mostly larvae and juveniles, from NNV is a major obstacle in hatcheries, and impedes the supply of young fish to farms. Hence, cost-effective ribavirin treatment should be considered as an efficient means to reduce the peril of NNV., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Bartonella infection was explored in wild animals from Israel. Golden jackals (Canis aureus), red foxes (Vulpes vulpes), rock hyraxes (Procavia capensis), southern white-breasted hedgehogs (Erinaceus concolor), social voles (Microtus socialis), Tristram's jirds (Meriones tristrami), Cairo spiny mice (Acomys cahirinus), house mice (Mus musculus) and Indian crested porcupines (Hystrix indica) were sampled and screened by molecular and isolation methods. Bartonella-DNA was detected in 46 animals: 9/70 (13%) golden jackals, 2/11 (18%) red foxes, 3/35 (9%) rock hyraxes, 1/3 (33%) southern white-breasted hedgehogs, 5/57 (9%) Cairo spiny mice, 25/43 (58%) Tristram's jirds and 1/6 (16%) house mice. Bartonella rochalimae and B. rochalimae-like were widespread among jackals, foxes, hyraxes and jirds. This report represents the first detection of this zoonotic Bartonella sp. in rock hyraxes and golden jackals. Moreover, DNA of Bartonella vinsonii subsp. berkhoffii, Bartonella acomydis, Candidatus Bartonella merieuxii and other uncharacterized genotypes were identified. Three different Bartonella strains were isolated from Tristram's jirds, and several genotypes were molecularly detected from these animals. Furthermore, this study reports the first detection of Bartonella infection in a southern hedgehog. Our study indicates that infection with zoonotic and other Bartonella species is widespread among wild animals and stresses their potential threat to public health.

Concentrations of Hg, Se, Cd, Cu, Zn, Fe, Mn and As, in kidney, liver, muscle and blubber from 7 specimens of Stenella coeruleoalba, stranded along the Israeli Mediterranean coast (IMC) from 2006 to 2011 (2011-series) were determined and compared to previous data on S. coeruleoalba from the IMC (2001-series). No differences were observed in essential and toxic elements concentrations, between the two series, except for hepatic Mn which was higher in the latter. Hg/Se molar ratios in blubber, kidney and liver increased linearly with log Hg concentrations, while muscle was more heterogenic in this respect. Means (±SD) of hepatic Hg concentrations (134±89 and 181±200mgkg(-1), from the 2011 and 2001 series, respectively) were similar to that found in 2007-2009 specimens from Spain, possibly reflecting the relatively high natural background levels of mercury in the Mediterranean Sea., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Nervous necrosis virus (NNV) is a member of the Betanodavirus genus that causes fatal diseases in over 40 species of fish worldwide. Mortality among NNV-infected fish larvae is almost 100%. In order to elucidate the mechanisms responsible for the susceptibility of fish larvae to NNV, we exposed zebrafish larvae to NNV by bath immersion at 2, 4, 6, and 8 days postfertilization (dpf). Here, we demonstrate that developing zebrafish embryos are resistant to NNV at 2 dpf due to the protection afforded by the egg chorion and, to a lesser extent, by the perivitelline fluid. The zebrafish larvae succumbed to NNV infection during a narrow time window around the 4th dpf, while 6- and 8-day-old larvae were much less sensitive, with mortalities of 24% and 28%, respectively., (Copyright © 2015, American Society for Microbiology. All Rights Reserved.)

Fleas are acknowledged vectors and reservoirs of various bacteria that present a wide range of pathogenicity. In this study, fleas collected from wild rodents from the Negev desert in southern Israel were tested for RickettsiaDNA by targeting the 16S rRNA (rrs) gene. Thirty-eight Xenopsylla ramesis, 91 Synosternus cleopatrae and 15 Leptopsylla flea pools (a total of 568 fleas) were screened. RickettsiaDNA was detected in 100% of the X. ramesis and in one S. cleopatrae flea pools. None of L. algira flea pools was found positive. All positive flea pools were further characterized by sequencing of five additional genetic loci (gltA, ompB, ompA, htrA and fusA). The molecular identification of the positive samples showed all sequences to be closely related to the 'Rickettsia felis-like' organisms (99-100% similarities in the six loci). To further investigate the association between 'R. felis-like' and X. ramesis fleas, ten additional single X. ramesis adult fleas collected from the wild and five laboratory-maintained X. ramesis imago, five larva pools (2-18 larvae per pool) and two egg pools (18 eggs per pool) were tested for the presence of 'R. felis-like' DNA. All samples were found positive by a specific ompAPCR assay, confirming the close association of this Rickettsia species with X. ramesis in all its life stages. These results suggest a symbiotic association between 'Rickettsia felis-like' and X. ramesis fleas., (© 2015 John Wiley & Sons Ltd.)

Epidemiological studies worldwide have reported a high prevalence and a great diversity of Bartonella species, both in rodents and their flea parasites. The interaction among Bartonella, wild rodents, and fleas reflects a high degree of adaptation among these organisms. Vertical and horizontal efficient Bartonella transmission pathways within flea communities and from fleas to rodents have been documented in competence studies, suggesting that fleas are key players in the transmission of Bartonella to rodents. Exploration of the ecological traits of rodents and their fleas may shed light on the mechanisms used by bartonellae to become established in these organisms. The present review explores the interrelations within the Bartonella-rodent-flea system. The role of the latter two components is emphasized.

Bartonella spp. are worldwide-distributed facultative intracellular bacteria that exhibit an immense genomic diversity across mammal and arthropod hosts. The occurrence of cattle-associated Bartonella species was investigated in the cattle tail louse Haematopinus quadripertusus and in dairy cattle blood from Israel. Lice were collected from cattle from two dairy farms during summer 2011, and both lice and cow blood samples were collected from additional seven farms during the successive winter. The lice were identified morphologically and molecularly using 18S rRNA sequencing. Thereafter, they were screened for Bartonella DNA by conventional and real-time PCR assays using four partial genetic loci (gltA, rpoB, ssrA, and internal transcribed spacer [ITS]). A potentially novel Bartonella variant, closely related to other ruminant bartonellae, was identified in 11 of 13 louse pools collected in summer. In the cattle blood, the prevalence of Bartonella infection was 38%, identified as B. bovis and B. henselae (24 and 12%, respectively). A third genotype, closely related to Bartonella melophagi and Bartonella chomelii (based on the ssrA gene) and to B. bovis (based on the ITS sequence) was identified in a single cow. The relatively high prevalence of these Bartonella species in cattle and the occurrence of phylogenetically diverse Bartonella variants in both cattle and their lice suggest the potential role of this animal system in the generation of Bartonella species diversity., (Copyright © 2014, American Society for Microbiology. All Rights Reserved.)

The composition of Bartonella infection was explored in wild Gerbillus andersoni rodents and their Synosternus cleopatrae fleas. Rodent blood samples and fleas were collected in two periods (two different seasons; 4 months apart) from juveniles and adult hosts, and their bartonellae lineages were identified by a 454-pyrosequencing analysis targeting a specific Bartonella citrate synthase gene (gltA) fragment. The rate of Bartonella spp. co-infection was estimated and the assemblage and distribution of bartonellae lineages across the samples with respect to ecological and phylogenetic distance similarities were analyzed. Moreover, environmental factors that could explain potential differences between samples were investigated. Out of the 91 bartonellae-positive samples, 89% were found to be co-infected with more than two phylogenetically distant Bartonella genotypes and additional closely related (but distinguishable) variants. These bartonellae lineages were distributed in a non-random manner, and a negative interaction between lineages was discovered. Interestingly, the overall composition of those infections greatly varied among samples. This variability was partially explained by factors, such as type of sample (blood versus fleas), flea sex and period of collection. This investigation sheds light on the patterns of Bartonella infection and the organization of Bartonella lineages in fleas and rodents in nature.

In this paper we present the concentrations of Hg, Cd, Se, Pb, Cu, Mn, Zn and Fe in organs of 6 non-common specimens of cetaceans that were stranded along the Israeli Mediterranean coast (IMC), during 2002-2010: two fin whales, one minke whale, one Cuvier's beaked whale, one rough-toothed dolphin, and one Risso's dolphin. Most of the specimens were calves stranded by accident. Concentrations of Hg and Cd were low in tissues of the baleen whales and higher in the toothed whales, with maximum concentrations of 1067 mg kg(-1) Hg in the liver of the Risso's dolphin and 29 mg kg(-1) Cd in the kidney of the Cuvier's beaked whale. As far as we are aware, this is the first report of trace elements in baleen whales in the Eastern Mediterranean, and the first report of trace elements in minke whale and rough-toothed dolphin in the Mediterranean., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

To determine the occurrence of feline bartonellosis in Israel, blood samples were collected from 179 stray and 155 domestic cats from 18 cities or villages in central and northcentral Israel. Samples were screened for Bartonella infection by culture isolation and molecular detection using high-resolution melt (HRM) real-time PCR assay targeting the 16S-23S rRNA internal transcribed spacer (ITS). All positive samples were confirmed by two additional HRM real-time PCR assays targeting two fragments of the β-subunit of RNA polymerase (rpoB) and the 16S rRNA genes. The prevalence of Bartonella spp. infection in the general tested population was 25.1% (84/334). A higher prevalence was detected in the stray (30.7%; 55/179) than the domestic cats (18.7%; 29/155). Bartonella henselae, Bartonella clarridgeiae, and Bartonella koehlerae were highly prevalent in both cat populations, however their distribution among the two populations varied significantly (p=0.016). B. clarridgeiae and B. koehlerae were found to be more prevalent in stray than domestic cats, whereas B. henselae was evenly distributed. Co-infection with two or more different Bartonella spp. was determined in 2.1% (7) of the cats. The ITS HRM real-time PCR assay used in this study was shown to have a greater screening power than bacterial isolation, detecting 94.0% (79/84) compared to 35.7% (30/84), respectively, of all positive samples. The high prevalence of these zoonotic Bartonella species, coupled with the overpopulation of stray cats, and increased numbers of domestic cats in the major urban centers in Israel represent a significant threat for the public health in this country.

Phosphoinositides and in particular L-α-phosphatidylinositol-4,5-bisphosphate (PIP2) are key lipids controlling many cellular events and serve as receptors for a large number of intracellular proteins. To quantitatively analyze protein-PIP2 interactions in vitro in a time-resolved manner, planar membranes on solid substrates are highly desirable. Here, we describe an optimized protocol to form PIP2 containing planar solid supported membranes on silicon surfaces by vesicle spreading. Supported lipid bilayers (SLBs) were obtained by spreading POPC/PIP2 (92:8) small unilamellar vesicles onto hydrophilic silicon substrates at a low pH of 4.8. These membranes were capable of binding ezrin, resulting in large protein coverage as concluded from reflectometric interference spectroscopy and fluorescence microscopy. As deduced from fluorescence microscopy, only under low pH conditions, a homogeneously appearing distribution of fluorescently labeled PIP2 molecules in the membrane was achieved. Fluorescence recovery after photobleaching experiments revealed that PIP2 is not mobile in the bottom layer of the SLBs, while PIP2 is fully mobile in the top layer with diffusion coefficients of about 3 μm(2)/s. This diffusion coefficient was considerably reduced by a factor of about 3 if ezrin has been bound to PIP2 in the membrane.

Pathogens use diverse pathways to infect host populations by vertical and/or horizontal routes. Horizontal transmission of bacteria belonging to the Bartonella genus via haematophagous vectors is well known. Vertical transmission of Bartonella species was also suggested to occur but its routes remain to be unveiled. In a previous study, we showed the absence of transovarial transmission of Bartonella species OE 1-1 in Xenopsylla ramesis fleas, and that fleas feeding on Bartonella-positive jirds produced Bartonella-positive gut voids. This current study aimed to investigate whether vertical nontransovarial transmission of Bartonella occurs in fleas. For this aim, the X. ramesis-Bartonella sp. OE 1-1 model was used. Four groups of fleas including Bartonella-positive and Bartonella-negative female fleas and larval offspring had access to either Bartonella-negative or Bartonella-positive gut voids and faeces. Sixteen per cent of flea offspring that had access to Bartonella-positive faeces and gut voids became Bartonella positive. Our findings demonstrate that Bartonella-positive flea faeces and gut voids are proper infection sources for flea larvae and indicate that vertical nontransovarial transmission of bartonellae occurs in fleas. This information broadens our understanding of Bartonella transmission routes in flea vectors and enlightens pathways of bartonellae transmission and maintenance in flea populations in nature., (© 2013 John Wiley & Sons Ltd.)

Polycystin-2 (PC2) trafficking has been proposed to be a result of the interaction of PIGEA14 with PC2 as a function of the phosphorylation state of PC2. Here, we investigated the interaction of PIGEA14 with the C-terminal part of polycystin-2 wild type (cPC2wt) and the pseudophosphorylated mutant (cPC2S812D) to first, quantify the binding affinity between cPC2 and PIGEA14 and second, to elucidate the influence of PC2 phosphorylation on PIGEA14 binding. Solid supported membranes composed of octanethiol/1,2-dioleoyl-sn-glycero-3-phosphocholine doped with the receptor lipid DOGS-NTA-Ni were used to attach PIGEA14 to the membrane via its hexahistidine tag. By means of the quartz crystal microbalance technique, binding affinities as well as kinetic constants of the interaction were extracted in a label-free manner by applying the scaled particle theory. The results show that the dissociation constant of cPC2 to PIGEA14 is in the 10 nM regime providing strong evidence of a very specific interaction of cPC2 with PIGEA14. The interaction of cPC2wt is twofold larger than that of cPC2S812D. The moderate higher binding affinity of cPC2wt to PIGEA14 is discussed in light of PC2 trafficking to the plasma membrane., (Copyright © 2013 Elsevier Inc. All rights reserved.)