1
|
Zhang LJ, Chen Q, Yang JX, Ge JQ. Immune responses and protective efficacy of American eel (Anguilla rostrata) immunized with a formalin-inactivated vaccine against Anguillid herpesvirus. FISH & SHELLFISH IMMUNOLOGY 2024; 144:109262. [PMID: 38040135 DOI: 10.1016/j.fsi.2023.109262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 11/14/2023] [Accepted: 11/26/2023] [Indexed: 12/03/2023]
Abstract
Anguillid herpesvirus 1 (AngHV), the causative agent of "mucus sloughing and hemorrhagic septicemia disease", causes serious infectious diseases in farmed eel. Among the effective prevention and control strategies, vaccination is one of the most effective approaches. However, no vaccine for AngHV is available. Our study developed a formalin-inactivated AngHV vaccine and evaluated its performance in American eels. Initially, AngHV-FJ, a strain of AngHV, was inactivated completely by 0.1 % formaldehyde, mixed with adjuvant Montanide ISA 763 A VG (763A). Then, vaccines containing different amount of antigen (3 × 106 PFU, 3 × 105 PFU, 3 × 104 PFU, 3 × 103 PFU) were immunized in each American eels. The results showed that the 3 × 105 PFU/fish was the proper dose. The inactivated AngHV vaccine was proven safe for American eels by back intramuscular injection. The results of twice immunization showed that antibody production peaked in the 8th week after the first immunization, and the antibody titer was 1:64,000. Furthermore, the immunized fishes challenged with AngHV (105 PFU/ml immersion) showed a significantly lower incidence rate (33.33 %) than the control group (95.65 %). The survival of the fish in the vaccine group (94.44 %) was significantly higher than the control group (60.87 %). The relative survival rate of the vaccinated group was 85.80 %. Also, vaccine group tissue collected at 7th d post-challenge showed reduced tissue damage and a lower virus load than the control group. The expression of cytokines of IL-1β, IFN-α, IFN-γ, Mx1, RIG-1, and IRF-3, were significantly lower in the vaccine group than the control group at the 7th and 14th d post-challenge. Overall, the formalin-inactivated AngHV vaccine was safe and had immune protective effects against AngHV infection.
Collapse
Affiliation(s)
- Li-Juan Zhang
- Institute of Biotechnology, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, China
| | - Qiang Chen
- Institute of Biotechnology, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, China
| | - Jin-Xian Yang
- Institute of Biotechnology, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, China
| | - Jun-Qing Ge
- Institute of Biotechnology, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, China.
| |
Collapse
|
2
|
Ruiz de Ybáñez MR, Del Río L, Flores-Flores C, Muñoz P, Berriatua E, Rubio S, Martínez-Carrasco C. Monitoring for Anguillicoloides crassus, Anguillid herpesvirus 1, aquabirnavirus EVE and rhabdovirus EVEX in the European eel population of southern Spain. JOURNAL OF FISH DISEASES 2023; 46:417-431. [PMID: 36651585 DOI: 10.1111/jfd.13754] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Revised: 12/23/2022] [Accepted: 01/09/2023] [Indexed: 06/17/2023]
Abstract
European eel is critically endangered in Europe. Among other stressors, pathogens are well-known to harm eels' fitness. One hundred and eighty-two eels were captured in three Eel Management Units in Andalucía (SE Spain) and analysed for Anguillicoloides crassus, Anguillid herpesvirus 1 (AngHV1), the rhabdovirus Eel Virus European X (EVEX) and the aquabirnavirus Eel Virus European (EVE). A. crassus adults and preadults were isolated and morphometrically identified, and the eel swimbladders were artificially digested to count A. crassus larvae. Also, eel tissues were examined by PCRs for the presence of viruses. EVEX and EVE were not detected in any of the eels. The estimated prevalence (95% confidence limits) was 71 (64-78)% for A. crassus and 35 (28-42)% for AngHV-1, varying these prevalences significantly between and within EMUs. Moreover, A. crassus prevalence was highest in smaller eels, in sites closest to the sea and eels sampled in the autumn. By contrast, AngHV-1 prevalence was highest in biggest eels, in sites far from the sea and sampled in the summer or winter. However, in mixed effects logistic models including site as a random variable, the risk of infection was associated with distance to the sea in both A. crassus and AngHV-1 infections and also to winter sampling in the case of AngHV-1 and not to other variables. These results are evidence that both pathogens are highly endemic in eels from Andalusian habitats. Further studies are needed to better understand the risk factors associated with these pathogens on eel populations.
Collapse
Affiliation(s)
- M Rocío Ruiz de Ybáñez
- Departamento de Sanidad Animal, Facultad de Veterinaria, Campus de Excelencia Internacional Regional "Campus Mare Nostrum", Universidad de Murcia, Murcia, Spain
| | - Laura Del Río
- Departamento de Sanidad Animal, Facultad de Veterinaria, Campus de Excelencia Internacional Regional "Campus Mare Nostrum", Universidad de Murcia, Murcia, Spain
| | - César Flores-Flores
- Sección de Biología Molecular, Área Científica y Técnica de Investigación, Universidad de Murcia, Murcia, Spain
| | - Pilar Muñoz
- Departamento de Sanidad Animal, Facultad de Veterinaria, Campus de Excelencia Internacional Regional "Campus Mare Nostrum", Universidad de Murcia, Murcia, Spain
| | - Eduardo Berriatua
- Departamento de Sanidad Animal, Facultad de Veterinaria, Campus de Excelencia Internacional Regional "Campus Mare Nostrum", Universidad de Murcia, Murcia, Spain
| | - Silvia Rubio
- Planificación Cinegética y Piscícola, Agencia de Medio Ambiente y Agua, Junta de Andalucía, Granada, Spain
| | - Carlos Martínez-Carrasco
- Departamento de Sanidad Animal, Facultad de Veterinaria, Campus de Excelencia Internacional Regional "Campus Mare Nostrum", Universidad de Murcia, Murcia, Spain
| |
Collapse
|
3
|
Wang H, Wan HT, Wu B, Jian J, Ng AHM, Chung CYL, Chow EYC, Zhang J, Wong AOL, Lai KP, Chan TF, Zhang EL, Wong CKC. A Chromosome-level assembly of the Japanese eel genome, insights into gene duplication and chromosomal reorganization. Gigascience 2022; 11:6883318. [PMID: 36480030 PMCID: PMC9730501 DOI: 10.1093/gigascience/giac120] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 09/26/2022] [Accepted: 11/15/2022] [Indexed: 12/13/2022] Open
Abstract
Japanese eels (Anguilla japonica) are commercially important species, harvested extensively for food. Currently, this and related species (American and European eels) are challenging to breed on a commercial basis. As a result, the wild stock is used for aquaculture. Moreover, climate change, habitat loss, water pollution, and altered ocean currents affect eel populations negatively. Accordingly, the International Union for Conservation of Nature lists Japanese eels as endangered and on its red list. Here we presented a high-quality genome assembly for Japanese eels and demonstrated that large chromosome reorganizations occurred in the events of third-round whole-genome duplications (3R-WRDs). Several chromosomal fusions and fissions have reduced the ancestral protochromosomal number of 25 to 19 in the Anguilla lineage. A phylogenetic analysis of the expanded gene families showed that the olfactory receptors (group δ and ζ genes) and voltage-gated Ca2+ channels expanded significantly. Both gene families are crucial for olfaction and neurophysiology. Additional tandem and proximal duplications occurred following 3R-WGD to acquire immune-related genes for an adaptive advantage against various pathogens. The Japanese eel assembly presented here can be used to study other Anguilla species relating to evolution and conservation.
Collapse
Affiliation(s)
- Hongbo Wang
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China,Department of Computer Science, Hong Kong Baptist University, Hong Kong SAR
| | - Hin Ting Wan
- Department of Biology, Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Hong Kong SAR
| | - Bin Wu
- BGI Genomics, BGI-Shenzhen, Shenzhen 518083, China
| | - Jianbo Jian
- BGI Genomics, BGI-Shenzhen, Shenzhen 518083, China
| | - Alice H M Ng
- Department of Biology, Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Hong Kong SAR
| | - Claire Yik-Lok Chung
- School of Life Sciences, State Key Laboratory of Agrobiotechnology, Hong Kong Bioinformatics Centre, the Chinese University of Hong Kong, Hong Kong SAR
| | - Eugene Yui-Ching Chow
- School of Life Sciences, State Key Laboratory of Agrobiotechnology, Hong Kong Bioinformatics Centre, the Chinese University of Hong Kong, Hong Kong SAR
| | - Jizhou Zhang
- School of Life Sciences, State Key Laboratory of Agrobiotechnology, Hong Kong Bioinformatics Centre, the Chinese University of Hong Kong, Hong Kong SAR
| | - Anderson O L Wong
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China,School of Biological Sciences, the University of Hong Kong, Hong Kong SAR
| | - Keng Po Lai
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China,Key Laboratory of Environmental Pollution and Integrative Omics, Guilin Medical University, Guilin, China
| | - Ting Fung Chan
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China,School of Life Sciences, State Key Laboratory of Agrobiotechnology, Hong Kong Bioinformatics Centre, the Chinese University of Hong Kong, Hong Kong SAR
| | - Eric Lu Zhang
- Correspondence address. Eric Lu Zhang, Department of Computer Science, Hong Kong Baptist University, Hong Kong SAR. E-mail:
| | - Chris Kong-Chu Wong
- Correspondence address. Chris K.C. Wong, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Croucher Institute for Environmental Sciences, Department of Biology, Hong Kong Baptist University, Hong Kong SAR. E-mail:
| |
Collapse
|
4
|
Danne L, Adamek M, Wonnemann H, Pieper T, Fey D, Hellmann J. Identification of virus infections of European eels intended for stocking measures. JOURNAL OF FISH DISEASES 2022; 45:1259-1266. [PMID: 35648620 DOI: 10.1111/jfd.13658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 04/25/2022] [Accepted: 04/27/2022] [Indexed: 06/15/2023]
Abstract
The spread of viral diseases in eels is suggested to severely affect the European eel (Anguilla anguilla) panmictic population. The European Commission has initiated the Eel Recovery Plan (Council Regulation No. 1100/2007) to try to return the European eel stock to more sustainable levels within that measures eel restocking. However, scientific evidence evaluating the efficacy of stocking remains scarce. In addition, knowledge about the impact and contribution of eel stocking on the distribution of infectious diseases is insufficient. In this study, we aimed to investigate virus infections in batches of eels intended for restocking. We analysed samples of glass eels from certified fisheries and farmed European eels from different aquaculture farms. All analysed eels were purchased within a North Rhine Westphalian conservation program. Via a combination of cell culture and qPCR-based techniques, we detected infections of glass eels with the rhabdovirus Eel Virus European X and anguillid herpesvirus 1 infections in farmed eels (10-15 cm).
Collapse
Affiliation(s)
- Linna Danne
- North Rhine Westphalian State Agency for Nature, Environment and Consumer Protection, Fisheries Ecology and Aquaculture, Kirchhundem, Germany
| | - Mikolaj Adamek
- Fish Disease Research Unit, Centre for Infection Medicine, University of Veterinary Medicine, Hannover, Germany
| | | | - Theresa Pieper
- North Rhine Westphalian State Agency for Nature, Environment and Consumer Protection, Fisheries Ecology and Aquaculture, Kirchhundem, Germany
| | - Daniel Fey
- North Rhine Westphalian State Agency for Nature, Environment and Consumer Protection, Fisheries Ecology and Aquaculture, Kirchhundem, Germany
| | - John Hellmann
- North Rhine Westphalian State Agency for Nature, Environment and Consumer Protection, Fisheries Ecology and Aquaculture, Kirchhundem, Germany
| |
Collapse
|
5
|
Parchemin C, Tapissier-Bontemps N, Sasal P, Faliex E. Anguilla sp. diseases diagnoses and treatments: The ideal methods at the crossroads of conservation and aquaculture purposes. JOURNAL OF FISH DISEASES 2022; 45:943-969. [PMID: 35526273 DOI: 10.1111/jfd.13634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 04/20/2022] [Accepted: 04/22/2022] [Indexed: 06/14/2023]
Abstract
Anguilla anguilla, A. japonica and A. rostrata are the most fished and consumed eel species. However, these species are Critically Endangered, Endangered and Endangered, respectively. A combination of factors is thought to be responsible for their decline including fisheries, climate change, habitat destruction, barriers to migration, pollution and pathogens. Among them, viruses, bacteria and parasites are causing weakening of wild eels and serious economic losses for fishermen and eel farmers. Early detection of pathogens is essential to provide appropriate responses both for conservation reasons and to limit economic losses. Classic diagnosis approaches are time consuming and invasive and usual treatments, for example, antipathogenic substances are becoming obsolete because of pathogen resistance and environmental impact problems. The need for early and non-invasive diagnostic methods as well as effective and environmentally friendly treatments has increased. Vaccine development and diet supplementation have known a growing interest since their use could allow prevention of diseases. In this review, we summarize the main pathogens-viruses, bacteria and parasites-of the three northern temperate eel species, the methods used to detect these pathogens and the different treatments used. We discussed and highlighted the need for non-invasive, rapid and efficient detection methods, as well as effective and environmentally friendly treatments for both conservation and aquaculture purposes.
Collapse
Affiliation(s)
- Christelle Parchemin
- Centre de Recherches Insulaires et Observatoire de l'Environnement (CRIOBE), Université de Perpignan, Perpignan Cedex, France
- Centre de Formation et de Recherche sur les Environnements Méditerranéens (CEFREM), Université de Perpignan, Perpignan Cedex, France
| | - Nathalie Tapissier-Bontemps
- Centre de Recherches Insulaires et Observatoire de l'Environnement (CRIOBE), Université de Perpignan, Perpignan Cedex, France
| | - Pierre Sasal
- Centre de Recherches Insulaires et Observatoire de l'Environnement (CRIOBE), Université de Perpignan, Perpignan Cedex, France
| | - Elisabeth Faliex
- Centre de Formation et de Recherche sur les Environnements Méditerranéens (CEFREM), Université de Perpignan, Perpignan Cedex, France
| |
Collapse
|