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Ying C, Hua Z, Ma F, Yang Y, Wang Y, Liu K, Yin G. Hepatic immune response of Coilia nasus infected with Anisakidae during ovarian development. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART D, GENOMICS & PROTEOMICS 2024; 52:101261. [PMID: 38897035 DOI: 10.1016/j.cbd.2024.101261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 05/29/2024] [Accepted: 05/30/2024] [Indexed: 06/21/2024]
Abstract
Anisakidae parasitism is a prevalent disease in wild populations of Coilia nasus, and can result in a significant loss of germplasm resources. To elucidate the immune response mechanism of C. nasus livers to Anisakidae infection, we collected and analysed 18 parasitic and 18 non-parasitic livers at gonadal developmental stages II, III, and V using histopathology, molecular biology and transcriptome methods. The hepatic portal area of the parasitic group exhibited an increase in the fibrous stroma and thickened hepatic arteries with positive Ly-6G staining, indicating inflammation and immune responses in the liver. Hepatocyte cytokine levels and the expression of liver function-related genes indicated that fish livers responded similarly to Anisakidae parasitism across different gonadal developmental stages. Oxidative stress indices showed more intense changes in stage II samples, whereas gene expression levels of Nrf2 and C3 were significantly increased in parasitised livers during stage III and V. Liver transcriptome sequencing identified 2575 differentially expressed genes between the parasitic and non-parasitic groups at the three gonadal developmental stages. KEGG pathway analysis showed that natural killer cell-mediated cytotoxicity, the NOD-like receptor signaling pathway, neutrophil extracellular trap formation, and other immune pathways were significantly enriched. Expression patterns varied across developmental stages, suggesting that innate immunity was primarily responsible for the liver immune response to Anisakidae infection during C. nasus migration, possibly related to water temperature changes or shifts in the gonadal developmental stage. In summary, this study investigated the immune response of C. nasus to Anisakidae parasitism under natural conditions, focusing on reproductive aspects and environmental changes, thereby establishing a foundation for elucidating the molecular mechanisms underlying the immune response of Anisakidae in C. nasus.
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Affiliation(s)
- Congping Ying
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Zhong Hua
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Fengjiao Ma
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Yanping Yang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Yinping Wang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Kai Liu
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China.
| | - Guojun Yin
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China; Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China.
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Lee YJ, Jun LJ, Kim YJ, Han JE, Ko YJ, Oh YE, Lee EJ, Lee J, Jeong JB. Comparison of specificity and sensitivity of diagnostic methods for Enteromyxum leei and Enteromyxum fugu detected from cultured tiger puffer, Takifugu rubripes in Korea. JOURNAL OF FISH DISEASES 2024; 47:e13865. [PMID: 37731267 DOI: 10.1111/jfd.13865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 09/03/2023] [Accepted: 09/07/2023] [Indexed: 09/22/2023]
Abstract
Enteromyxum leei and Enteromyxum fugu, which are myxosporean parasites, were first found in cultured tiger puffer Takifugu rubripes in Korea. We collected four tiger puffers that showed severe emaciation signs for our experiments. DNA sequencing was confirmed that the tiger puffers were coinfected with E. leei and E. fugu. Furthermore, similar amounts of E. leei and E. fugu were confirmed using real-time PCR in the intestine. To the best of our knowledge, there have been no reports of E. fugu infection in the olive flounder Paralichthys olivaceus. However, the diagnosis of inflowing water, discharged water and olive flounder samples using highly sensitive diagnostic methods confirmed the presence of E. fugu in water and fish samples from olive flounder farms near the tiger puffer farm. Therefore, the present study aimed to develop highly sensitive diagnostic methods such as real-time and two-step PCR for early diagnosis and follow-up of the emaciation disease and multiplex PCR for rapid diagnosis. The multiplex PCR method exhibited the same sensitivity as the one-step PCR method developed in this study, demonstrating its efficacy for rapid diagnosis. Therefore, the suggested methods can be utilized for the early diagnosis and rapid diagnosis of emaciation diseases and reduction of economic losses through rapid disease control.
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Affiliation(s)
- Young Juhn Lee
- Department of Marine Life Science, Jeju National University, Jeju City, Republic of Korea
| | - Lyu Jin Jun
- Department of Marine Life Science, Jeju National University, Jeju City, Republic of Korea
| | - Ye Ji Kim
- Department of Marine Life Science, Jeju National University, Jeju City, Republic of Korea
| | - Ji Eun Han
- Department of Marine Life Science, Jeju National University, Jeju City, Republic of Korea
| | - Ye Jin Ko
- Department of Marine Life Science, Jeju National University, Jeju City, Republic of Korea
| | - Yeong Eun Oh
- Department of Marine Life Science, Jeju National University, Jeju City, Republic of Korea
| | - Eung Joon Lee
- Department of Marine Life Science, Jeju National University, Jeju City, Republic of Korea
| | - Jehee Lee
- Department of Marine Life Science, Jeju National University, Jeju City, Republic of Korea
| | - Joon Bum Jeong
- Department of Marine Life Science, Jeju National University, Jeju City, Republic of Korea
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Liu Y, Cheng J, Xia Y, Li X, Liu Y, Liu PF. Response mechanism of gut microbiome and metabolism of European seabass (Dicentrarchus labrax) to temperature stress. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 813:151786. [PMID: 34942265 DOI: 10.1016/j.scitotenv.2021.151786] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 11/08/2021] [Accepted: 11/14/2021] [Indexed: 05/10/2023]
Abstract
In animals, the gut microbiome is vital to growth, and changes in the composition of these microbial communities may affect growth and adaptability to the environment. Temperature is another important factor that influences the healthy growth of animals. To date, the mechanism by which juvenile European seabass (Dicentrarchus labrax) and their symbiotic flora adapt to changes in environmental temperature is not well understood. Therefore, we evaluated the effect of temperature on the gut microbiota and metabolism of European seabass juveniles. We used 16S rRNA gene amplicon sequencing and non-targeted liquid chromatography with tandem mass spectrometry (LC-MS/MS)-based metabolomics to study the gut microbes of European seabass after 60 days of rearing of water temperature at 10 °C (T1), 15 °C (T2) and 20 °C (T3). At the phylum level, the abundance of the gut microbiota did not differ significantly among the three groups after 60 days of cultivation. At the genus level, however, the abundance of Faecalibacterium, Filifactor, Butyricicoccus, and Erysipelotrichaceae UCG-006 in the intestines differed significantly among the temperature groups. Compared with T2, the relative abundance of Filifactor in T1 was significantly increased, while Faecalibacterium was significantly decreased, while the relative abundance of Butyricicoccus and Erysipelotrichaceae UCG-006 in T3 was significantly increased. The LC-MS/MS analysis revealed 107 metabolites in the 10 °C group and 68 metabolites in the 20 °C group that differed significantly from those in the intestines of fish in the 15 °C control group. These metabolites are closely related to several metabolic pathways, including amino acid metabolism, glucose and lipid metabolism, and the tricarboxylic acid cycle. Correlation analysis of the Intestine microbiota, metabolic pathways, and metabolites identified metabolic pathways and metabolites that were strongly related to the observed significant differences in the microbiome among the temperature groups. These results show that temperature can induce significant changes in the gut microbiota and metabolism of European seabass juveniles, and that significant changes in metabolites may be mediated through the interaction of the microbiome and metabolic pathways.
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Affiliation(s)
- Yanyun Liu
- College of Fisheries and Life Science, Dalian Ocean University, Dalian 116023, China; Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University) Ministry of Education, 116023, China
| | - Jianxin Cheng
- Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University) Ministry of Education, 116023, China; College of Life Science, Liaoning Normal University, Dalian 116081, China
| | - Yuqing Xia
- Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University) Ministry of Education, 116023, China; School of Marine Sciences, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Xiaohao Li
- Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University) Ministry of Education, 116023, China; College of Marine Technology and Environment, Dalian Ocean University, Dalian 116023, China
| | - Ying Liu
- College of Fisheries and Life Science, Dalian Ocean University, Dalian 116023, China; Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University) Ministry of Education, 116023, China; College of Marine Technology and Environment, Dalian Ocean University, Dalian 116023, China
| | - Peng-Fei Liu
- Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University) Ministry of Education, 116023, China; College of Marine Technology and Environment, Dalian Ocean University, Dalian 116023, China.
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Holzer AS, Piazzon MC, Barrett D, Bartholomew JL, Sitjà-Bobadilla A. To React or Not to React: The Dilemma of Fish Immune Systems Facing Myxozoan Infections. Front Immunol 2021; 12:734238. [PMID: 34603313 PMCID: PMC8481699 DOI: 10.3389/fimmu.2021.734238] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/01/2021] [Indexed: 11/13/2022] Open
Abstract
Myxozoans are microscopic, metazoan, obligate parasites, belonging to the phylum Cnidaria. In contrast to the free-living lifestyle of most members of this taxon, myxozoans have complex life cycles alternating between vertebrate and invertebrate hosts. Vertebrate hosts are primarily fish, although they are also reported from amphibians, reptiles, trematodes, mollusks, birds and mammals. Invertebrate hosts include annelids and bryozoans. Most myxozoans are not overtly pathogenic to fish hosts, but some are responsible for severe economic losses in fisheries and aquaculture. In both scenarios, the interaction between the parasite and the host immune system is key to explain such different outcomes of this relationship. Innate immune responses contribute to the resistance of certain fish strains and species, and the absence or low levels of some innate and regulatory factors explain the high pathogenicity of some infections. In many cases, immune evasion explains the absence of a host response and allows the parasite to proliferate covertly during the first stages of the infection. In some infections, the lack of an appropriate regulatory response results in an excessive inflammatory response, causing immunopathological consequences that are worse than inflicted by the parasite itself. This review will update the available information about the immune responses against Myxozoa, with special focus on T and B lymphocyte and immunoglobulin responses, how these immune effectors are modulated by different biotic and abiotic factors, and on the mechanisms of immune evasion targeting specific immune effectors. The current and future design of control strategies for myxozoan diseases is based on understanding this myxozoan-fish interaction, and immune-based strategies such as improvement of innate and specific factors through diets and additives, host genetic selection, passive immunization and vaccination, are starting to be considered.
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Affiliation(s)
- Astrid S Holzer
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czechia
| | - M Carla Piazzon
- Fish Pathology Group, Institute of Aquaculture Torre de la Sal - Consejo Superior de Investigaciones Científicas (IATS-CSIC), Castellón, Spain
| | - Damien Barrett
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Jerri L Bartholomew
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Ariadna Sitjà-Bobadilla
- Fish Pathology Group, Institute of Aquaculture Torre de la Sal - Consejo Superior de Investigaciones Científicas (IATS-CSIC), Castellón, Spain
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Cascarano MC, Stavrakidis-Zachou O, Mladineo I, Thompson KD, Papandroulakis N, Katharios P. Mediterranean Aquaculture in a Changing Climate: Temperature Effects on Pathogens and Diseases of Three Farmed Fish Species. Pathogens 2021; 10:1205. [PMID: 34578236 PMCID: PMC8466566 DOI: 10.3390/pathogens10091205] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/03/2021] [Accepted: 09/13/2021] [Indexed: 02/07/2023] Open
Abstract
Climate change is expected to have a drastic effect on aquaculture worldwide. As we move forward with the agenda to increase and diversify aquaculture production, rising temperatures will have a progressively relevant impact on fish farming, linked to a multitude of issues associated with fish welfare. Temperature affects the physiology of both fish and pathogens, and has the potential to lead to significant increases in disease outbreaks within aquaculture systems, resulting in severe financial impacts. Significant shifts in future temperature regimes are projected for the Mediterranean Sea. We therefore aim to review and discuss the existing knowledge relating to disease outbreaks in the context of climate change in Mediterranean finfish aquaculture. The objective is to describe the effects of temperature on the physiology of both fish and pathogens, and moreover to list and discuss the principal diseases of the three main fish species farmed in the Mediterranean, namely gilthead seabream (Sparus aurata), European seabass (Dicentrarchus labrax), and meagre (Argyrosomus regius). We will attempt to link the pathology of each disease to a specific temperature range, while discussing potential future disease threats associated with the available climate change trends for the Mediterranean Sea.
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Affiliation(s)
- Maria Chiara Cascarano
- Hellenic Centre for Marine Research, Institute of Marine Biology, Biotechnology and Aquaculture, 71500 Heraklion, Greece; (M.C.C.); (O.S.-Z.); (N.P.)
- Department of Biology, University of Crete, 71003 Heraklion, Greece
| | - Orestis Stavrakidis-Zachou
- Hellenic Centre for Marine Research, Institute of Marine Biology, Biotechnology and Aquaculture, 71500 Heraklion, Greece; (M.C.C.); (O.S.-Z.); (N.P.)
- Department of Biology, University of Crete, 71003 Heraklion, Greece
| | - Ivona Mladineo
- Biology Center of Czech Academy of Sciences, Laboratory of Functional Helminthology, Institute of Parasitology, 370 05 Ceske Budejovice, Czech Republic;
| | - Kim D. Thompson
- Vaccines and Diagnostics, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian EH26 0PZ, UK;
| | - Nikos Papandroulakis
- Hellenic Centre for Marine Research, Institute of Marine Biology, Biotechnology and Aquaculture, 71500 Heraklion, Greece; (M.C.C.); (O.S.-Z.); (N.P.)
| | - Pantelis Katharios
- Hellenic Centre for Marine Research, Institute of Marine Biology, Biotechnology and Aquaculture, 71500 Heraklion, Greece; (M.C.C.); (O.S.-Z.); (N.P.)
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Experimental Horizontal Transmission of Enterospora nucleophila (Microsporea: Enterocytozoonidae) in Gilthead Sea Bream ( Sparus aurata). Animals (Basel) 2021; 11:ani11020362. [PMID: 33535588 PMCID: PMC7912876 DOI: 10.3390/ani11020362] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/23/2021] [Accepted: 01/25/2021] [Indexed: 11/17/2022] Open
Abstract
Enterospora nucleophila is a microsporidian enteroparasite that infects mainly the intestine of gilthead sea bream (Sparus aurata), leading to an emaciative syndrome. Thus far, the only available information about this infection comes from natural outbreaks in farmed fish. The aim of the present study was to determine whether E. nucleophila could be transmitted horizontally using naturally infected fish as donors, and to establish an experimental in vivo procedure to study this host-parasite model without depending on natural infections. Naïve fish were exposed to the infection by cohabitation, effluent, or intubated either orally or anally with intestinal scrapings of donor fish in four different trials. We succeeded in detecting parasite in naïve fish in all the challenges, but the infection level and the disease signs were always milder than in donor fish. The parasite was found in peripheral blood of naïve fish at 4 weeks post-challenge (wpc) in oral and effluent routes, and up to 12 wpc in the anal transmission trial. Molecular diagnosis detected E. nucleophila in other organs besides intestine, such as gills, liver, stomach or heart, although the intensity was not as high as in the target tissue. The infection tended to disappear through time in all the challenge routes assayed, except in the anal infection route.
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Picard-Sánchez A, Estensoro I, Perdiguero P, Del Pozo R, Tafalla C, Piazzon MC, Sitjà-Bobadilla A. Passive Immunization Delays Disease Outcome in Gilthead Sea Bream Infected With Enteromyxum leei (Myxozoa), Despite the Moderate Changes in IgM and IgT Repertoire. Front Immunol 2020; 11:581361. [PMID: 33013935 PMCID: PMC7516018 DOI: 10.3389/fimmu.2020.581361] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 08/17/2020] [Indexed: 12/16/2022] Open
Abstract
Passive immunization constitutes an emerging field of interest in aquaculture, particularly with the restrictions for antibiotic use. Enteromyxum leei is a myxozoan intestinal parasite that invades the paracellular space of the intestinal epithelium, producing a slow-progressing disease, leading to anorexia, cachexia and mortalities. We have previously demonstrated that gilthead sea bream (GSB, Sparus aurata) that survive E. leei infection become resistant upon re-exposure, and this resistance is directly related to the presence of high levels of specific IgM in serum. Thus, the current work was aimed to determine if passive immunization could help to prevent enteromyxosis in GSB and to study in detail the nature of these protective antibodies. Serum from a pool of resistant (SUR) or naïve (NAI) animals was intracoelomically injected 24 h prior to the E. leei-effluent challenge and at 9 days post-challenge (dpc). Effluent challenge lasted for 23 days, and then the injected groups were allocated in separate tanks with clean water. A non-lethal parasite diagnosis was performed at 56 dpc. At the final sampling (100 dpc), blood, serum and tissues were collected for histology, molecular diagnosis and the detection of circulating antibodies. In parallel, we performed an immunoglobulin repertoire analysis of the fish generating SUR and NAI sera. The results showed that, fish injected with parasite-specific antibodies (spAbs) became infected with the parasite, but showed lower disease signs and intensity of infection than the other groups, indicating a later establishment of the parasite. Repertoire analysis revealed that E. leei induced a polyclonal expansion of diverse IgM and IgT subsets that could be in part an evasion strategy of the parasite. Nonetheless, GSB was able to produce sufficient levels of parasite-spAbs to avoid re-infection of surviving animals and confer certain degree of protection upon passive transfer of antibodies. These results highlight the crucial role of spAb responses against E. leei and set the basis for the development of effective treatment or prophylactic methods for aquaculture.
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Affiliation(s)
- Amparo Picard-Sánchez
- Fish Pathology Group, Institute of Aquaculture Torre de la Sal (IATS-CSIC), Castellón, Spain
| | - Itziar Estensoro
- Fish Pathology Group, Institute of Aquaculture Torre de la Sal (IATS-CSIC), Castellón, Spain
| | | | - Raquel Del Pozo
- Fish Pathology Group, Institute of Aquaculture Torre de la Sal (IATS-CSIC), Castellón, Spain
| | | | - M Carla Piazzon
- Fish Pathology Group, Institute of Aquaculture Torre de la Sal (IATS-CSIC), Castellón, Spain
| | - Ariadna Sitjà-Bobadilla
- Fish Pathology Group, Institute of Aquaculture Torre de la Sal (IATS-CSIC), Castellón, Spain
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Freeman MA, Yanagida T, Kristmundsson À. A novel histozoic myxosporean, Enteromyxum caesio n. sp., infecting the redbelly yellowtail fusilier, Caesio cuning, with the creation of the Enteromyxidae n. fam., to formally accommodate this commercially important genus. PeerJ 2020; 8:e9529. [PMID: 32742799 PMCID: PMC7367052 DOI: 10.7717/peerj.9529] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 06/22/2020] [Indexed: 12/27/2022] Open
Abstract
Gastrointestinal myxosporean parasites from the genus Enteromyxum are known to cause severe disease, resulting in high mortalities in numerous species of cultured marine fishes globally. Originally described as Myxidium spp., they were transferred to a new genus, Enteromyxum, to emphasize their novel characteristics. Their retention in the family Myxidiidae at the time was warranted, but more comprehensive phylogenetic analyses have since demonstrated the need for a new family for these parasites. We discovered a novel Enteromyxum in wild fish from Malaysia and herein describe the fourth species in the genus and erect a new family, the Enteromyxidae n. fam., to accommodate them. Enteromyxum caesio n. sp. is described infecting the tissues of the stomach in the redbelly yellowtail fusilier, Caesio cuning, from Malaysia. The new species is distinct from all others in the genus, as the myxospores although morphologically similar, are significantly smaller in size. Furthermore, small subunit ribosomal DNA sequence data reveal that E. caesio is <84% similar to others in the genus, but collectively they form a robust and discrete clade, the Enteromyxidae n. fam., which is placed as a sister taxon to other histozoic marine myxosporeans. In addition, we describe, using transmission electron microscopy, the epicellular stages of Enteromyxum fugu and show a scanning electron micrograph of a mature myxospore of E. caesio detailing the otherwise indistinct sutural line, features of the polar capsules and spore valve ridges. The Enteromyxidae n. fam. is a commercially important group of parasites infecting the gastrointestinal tract of marine fishes and the histozoic species can cause the disease enteromyxosis in intensive finfish aquaculture facilities. Epicellular and sloughed histozoic stages are responsible for fish-to-fish transmission in net pen aquaculture systems but actinospores from an annelid host are thought to be necessary for transmission to fish in the wild.
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Affiliation(s)
- Mark A Freeman
- Department of Biomedical Sciences, Ross University School of Veterinary Medicine, Basseterre, Saint Kitts and Nevis
| | - Tetsuya Yanagida
- Laboratory of Veterinary Parasitology, Joint Faculty of Veterinary Medicine, Yamaguchi University, Yoshida, Yamaguchi, Japan
| | - Àrni Kristmundsson
- Institute for Experimental Pathology at Keldur, University of Iceland, Reykjavík, Iceland
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