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Esposito G, Bergagna S, Colussi S, Shahin K, Rosa R, Volpatti D, Faggio C, Mossotto C, Gabetti A, Maganza A, Bozzetta E, Prearo M, Pastorino P. Changes in blood serum parameters in farmed rainbow trout (Oncorhynchus mykiss) during a piscine lactococcosis outbreak. JOURNAL OF FISH DISEASES 2024:e13994. [PMID: 38953153 DOI: 10.1111/jfd.13994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2024] [Revised: 06/12/2024] [Accepted: 06/17/2024] [Indexed: 07/03/2024]
Abstract
The aquaculture sector plays a vital role in global food security, yet it grapples with significant challenges posed by infectious diseases. Piscine lactococcosis is one of the significant threats in rainbow trout aquaculture due to its potential to cause severe economic losses through mortalities, reduced growth rates, and increased susceptibility to other pathogens. It poses challenges in disease management strategies, impacting the sustainability and profitability of rainbow trout farming. The current study focuses on the variations in serum blood parameters of farmed rainbow trout Oncorhynchus mykiss during a lactococcosis outbreak caused by Lactococcus garvieae. Blood samples were collected for biochemical analysis, fish were examined for parasites and bacteria, and DNA from bacterial colonies was PCR-amplified and sequenced for identification. Overall, 13 biochemical parameters, including proteins, enzymes, lipids, chemicals, and minerals, were measured in serum blood samples from both diseased and healthy fish. The results indicate significant alterations in the levels of these parameters during the outbreak, highlighting the impact of infections on the blood profile of farmed rainbow trout. Urea levels were significantly higher in diseased fish compared to controls, and creatinine, phosphorus, and magnesium also showed similar trends. Alanine aminotransferase and total protein levels were higher in control fish. Chloride levels differed significantly between groups. Iron levels were higher in controls and lower in diseased fish. No significant differences were found in other parameters. This study reveals significant changes in serum blood parameters of rainbow trout during a lactococcosis outbreak caused by L. garvieae. These changes highlight the potential of these parameters as tools for monitoring health status, stress, and aquaculture management. Continuous monitoring can provide valuable insights into disease severity and overall fish health, aiding in the development of improved management practices. The presented data contribute to understanding the pathophysiology of piscine lactococcosis and developing effective mitigation strategies for farmed rainbow trout.
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Affiliation(s)
- Giuseppe Esposito
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Stefania Bergagna
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Silvia Colussi
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Khalid Shahin
- Aquatic Animal Diseases Laboratory, Aquaculture Department, National Institute of Oceanography and Fisheries, Suez, Egypt
| | - Roberta Rosa
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Donatella Volpatti
- Dipartimento di Scienze Agroalimentari, Ambientali e Animali, University of Udine, Udine, Italy
| | - Caterina Faggio
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche e Ambientali, University of Messina, Messina, Italy
- Dipartimento di Biotecnologie Marine Ecosostenibili, Stazione Zoologica Anton Dohrn, Naples, Italy
| | - Camilla Mossotto
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Alice Gabetti
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Alessandra Maganza
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Elena Bozzetta
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Marino Prearo
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Paolo Pastorino
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
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Jantrakajorn S, Suyapoh W, Wongtavatchai J. Characterization of Lactococcus garvieae and Streptococcus agalactiae in cultured red tilapia Oreochromis sp. in Thailand. JOURNAL OF AQUATIC ANIMAL HEALTH 2024; 36:192-202. [PMID: 38632692 DOI: 10.1002/aah.10217] [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: 09/16/2023] [Revised: 01/04/2024] [Accepted: 02/20/2024] [Indexed: 04/19/2024]
Abstract
OBJECTIVE Acute mortality with clinical symptoms of streptococcal-like infections was observed in red tilapia Oreochromis sp. cultured in floating cages in Prachin Buri Province, Thailand, during May 2023. Herein, we identified an emerging pathogen, Lactococcus garvieae, as the etiological agent. METHODS After bacterial isolation from the brain and kidney of diseased fish, identification was performed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and the VITEK 2 system. Sequencing of the 16S ribosomal RNA (rRNA) gene and phylogenetic analysis were applied to confirm bacterial species. Antimicrobial susceptibility testing was conducted. Histopathological findings in the brain, kidney, spleen, liver, and heart were evaluated. RESULT From 20 fish samples, L. garvieae (n = 18 isolates) and Streptococcus agalactiae (n = 2 isolates) were identified. A phylogenetic tree of the 16S rRNA gene revealed that Thai isolates of either L. garvieae or S. agalactiae clustered with reference piscine isolates from intercontinental locations. Our isolates showed resistance against quinolones while being susceptible to other antimicrobials. Histopathological changes demonstrated severe septicemic conditions, with more invasive lesions-especially in the heart and liver-being apparent in L. garvieae-infected fish compared to S. agalactiae-infected fish. CONCLUSION This study represents the first reported outbreak of L. garvieae with a concurrent S. agalactiae infection in farmed red tilapia in Thailand.
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Affiliation(s)
| | - Watcharapol Suyapoh
- Faculty of Veterinary Science, Prince of Songkla University, Songkhla, Thailand
- World Health Organization Collaborating Center for Research and Control of Opisthorchiasis (Southeast Asian Liver Fluke Disease), Tropical Disease Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Janenuj Wongtavatchai
- Department of Veterinary Medicine, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand
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Heckman TI, Yazdi Z, Older CE, Griffin MJ, Waldbieser GC, Chow AM, Medina Silva I, Anenson KM, García JC, LaFrentz BR, Slavic D, Toohey-Kurth KL, Yant P, Fritz HM, Henderson EE, McDowall R, Cai H, Adkison M, Soto E. Redefining piscine lactococcosis. Appl Environ Microbiol 2024; 90:e0234923. [PMID: 38597602 PMCID: PMC11107168 DOI: 10.1128/aem.02349-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Accepted: 03/10/2024] [Indexed: 04/11/2024] Open
Abstract
Piscine lactococcosis is a significant threat to cultured and wild fish populations worldwide. The disease typically presents as a per-acute to acute hemorrhagic septicemia causing high morbidity and mortality, recalcitrant to antimicrobial treatment or management interventions. Historically, the disease was attributed to the gram-positive pathogen Lactococcus garvieae. However, recent work has revealed three distinct lactococcosis-causing bacteria (LCB)-L. garvieae, L. petauri, and L. formosensis-which are phenotypically and genetically similar, leading to widespread misidentification. An update on our understanding of lactococcosis and improved methods for identification are urgently needed. To this end, we used representative isolates from each of the three LCB species to compare currently available and recently developed molecular and phenotypic typing assays, including whole-genome sequencing (WGS), end-point and quantitative PCR (qPCR) assays, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), API 20 Strep and Biolog systems, fatty acid methyl ester analysis (FAME), and Sensititre antimicrobial profiling. Apart from WGS, sequencing of the gyrB gene was the only method capable of consistent and accurate identification to the species and strain level. A qPCR assay based on a putative glycosyltransferase gene was also able to distinguish L. petauri from L. garvieae/formosensis. Biochemical tests and MALDI-TOF MS showed some species-specific patterns in sugar and fatty acid metabolism or protein profiles but should be complemented by additional analyses. The LCB demonstrated overlap in host and geographic range, but there were relevant differences in host specificity, regional prevalence, and antimicrobial susceptibility impacting disease treatment and prevention. IMPORTANCE Lactococcosis affects a broad range of host species, including fish from cold, temperate, and warm freshwater or marine environments, as well as several terrestrial animals, including humans. As such, lactococcosis is a disease of concern for animal and ecosystem health. The disease is endemic in European and Asian aquaculture but is rapidly encroaching on ecologically and economically important fish populations across the Americas. Piscine lactococcosis is difficult to manage, with issues of vaccine escape, ineffective antimicrobial treatment, and the development of carrier fish or biofilms leading to recurrent outbreaks. Our understanding of the disease is also widely outdated. The accepted etiologic agent of lactococcosis is Lactococcus garvieae. However, historical misidentification has masked contributions from two additional species, L. petauri and L. formosensis, which are indistinguishable from L. garvieae by common diagnostic methods. This work is the first comprehensive characterization of all three agents and provides direct recommendations for species-specific diagnosis and management.
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Affiliation(s)
- Taylor I. Heckman
- Department of Medicine & Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Zeinab Yazdi
- Department of Medicine & Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Caitlin E. Older
- USDA-ARS, Warmwater Aquaculture Research Unit, Stoneville, Mississippi, USA
| | - Matt J. Griffin
- College of Veterinary Medicine, Mississippi State University, Stoneville, Mississippi, USA
| | | | - Alexander M. Chow
- Department of Medicine & Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Isabella Medina Silva
- Department of Medicine & Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Kelsey M. Anenson
- Department of Medicine & Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Julio C. García
- USDA-ARS, Aquatic Animal Health Research Unit, Auburn, Alabama, USA
| | | | - Durda Slavic
- Animal Health Laboratory, University of Guelph, Ontario, Canada
| | - Kathy L. Toohey-Kurth
- California Animal Health and Food Safety Laboratory, University of California, Davis, California, USA
| | - Paula Yant
- California Animal Health and Food Safety Laboratory, University of California, Davis, California, USA
| | - Heather M. Fritz
- California Animal Health and Food Safety Laboratory, University of California, Davis, California, USA
| | - Eileen E. Henderson
- California Animal Health and Food Safety Laboratory, University of California, Davis, California, USA
| | | | - Hugh Cai
- Animal Health Laboratory, University of Guelph, Ontario, Canada
| | - Mark Adkison
- California Department of Fish and Wildlife, Rancho Cordova, California, USA
| | - Esteban Soto
- Department of Medicine & Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
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Littman EM, Heckman TI, Yazdi Z, Veek T, Mukkatira K, Adkison M, Powell A, Camus A, Soto E. Temperature-associated virulence, species susceptibility and interspecies transmission of a Lactococcus petauri strain from rainbow trout. DISEASES OF AQUATIC ORGANISMS 2023; 155:147-158. [PMID: 37706645 DOI: 10.3354/dao03747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/15/2023]
Abstract
Lactococcus petauri is an important emergent aquaculture pathogen in the USA. To better understand environmental conditions conducive to piscine lactococcosis and the susceptibility of fish species, laboratory-controlled challenges were used as models of infection. Rainbow trout Oncorhynchus mykiss maintained at 13 or 18°C were challenged by intracoelomic (ICe) injection with 101, 103 or 105 colony-forming units per fish (CFU fish-1) and monitored for 21 d. At 13°C, trout experienced mortalities of 7, 7 and 0%, and bacterial persistence of 0, 20 and 0% in survivors, respectively. When exposed to the same bacterial doses, trout maintained at 18°C experienced mortalities of 59, 84 and 91%, and bacterial persistence of 60, 66 and 0% in survivors, confirming a significant role of temperature in the pathogenesis of lactococcosis. Additionally, the susceptibility of rainbow trout, Chinook salmon Oncorhynchus tshawytscha, white sturgeon Acipenser transmontanus, Nile tilapia Oreochromis niloticus, and koi Cyprinus carpio to infection by L. petauri was compared using ICe challenges at 18°C. Trout and salmon experienced 96 and 56% cumulative mortality, respectively, and 17% of surviving salmon remained persistently infected. There were no mortalities in the other fish species, and no culturable bacteria recovered at the end of the challenge. However, when surviving fish were used in further cohabitation trials, naïve trout housed with previously exposed tilapia exhibited 6% mortality, demonstrating that non-salmonids can become sub-clinical carriers of this pathogen. The data obtained provide useful information regarding temperature-associated virulence, fish species susceptibility, and potential carrier transmission of L. petauri that can be used in the development of better management practices to protect against piscine lactococcosis.
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Affiliation(s)
- Eric Maxwell Littman
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
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Abraham T, Yazdi Z, Littman E, Shahin K, Heckman TI, Quijano Cardé EM, Nguyen DT, Hu R, Adkison M, Veek T, Mukkatira K, Richey C, Kwak K, Mohammed HH, Ortega C, Avendaño-Herrera R, Keleher W, LePage V, Gardner I, Welch TJ, Soto E. Detection and virulence of Lactococcus garvieae and L. petauri from four lakes in southern California. JOURNAL OF AQUATIC ANIMAL HEALTH 2023; 35:187-198. [PMID: 37749801 DOI: 10.1002/aah.10188] [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: 10/14/2022] [Revised: 04/24/2023] [Accepted: 04/29/2023] [Indexed: 09/27/2023]
Abstract
OBJECTIVE The first objective of the study aimed to detect the presence of Lactococcus petauri, L. garvieae, and L. formosensis in fish (n = 359) and environmental (n = 161) samples from four lakes near an affected fish farm in California during an outbreak in 2020. The second objective was to compare the virulence of the Lactococcus spp. in Rainbow Trout Oncorhynchus mykiss and Largemouth Bass Micropterus salmoides. METHODS Standard bacterial culture methods were used to isolate Lactococcus spp. from brain and posterior kidney of sampled fish from the four lakes. Quantitative PCR (qPCR) was utilized to detect Lactococcus spp. DNA in fish tissues and environmental samples from the four lakes. Laboratory controlled challenges were conducted by injecting fish intracoelomically with representative isolates of L. petauri (n = 17), L. garvieae (n = 2), or L. formosensis (n = 4), and monitored for 14 days postchallenge (dpc). RESULT Lactococcus garvieae was isolated from the brains of two Largemouth Bass in one of the lakes. Lactococcus spp. were detected in 14 fish (8 Bluegills Lepomis macrochirus and 6 Largemouth Bass) from 3 out of the 4 lakes using a qPCR assay. Of the collected environmental samples, all 4 lakes tested positive for Lactococcus spp. in the soil samples, while 2 of the 4 lakes tested positive in the water samples through qPCR. Challenged Largemouth Bass did not show any signs of infection postinjection throughout the challenge period. Rainbow Trout infected with L. petauri showed clinical signs within 3 dpc and presented a significantly higher cumulative mortality (62.4%; p < 0.0001) at 14 dpc when compared to L. garvieae (0%) and L. formosensis (7.5%) treatments. CONCLUSION The study suggests that qPCR can be used for environmental DNA monitoring of Lactococcus spp. and demonstrates virulence diversity between the etiological agents of piscine lactococcosis.
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Affiliation(s)
- Taylor Abraham
- School of Veterinary Medicine, University of California-Davis, Davis, California, USA
| | - Zeinab Yazdi
- School of Veterinary Medicine, University of California-Davis, Davis, California, USA
| | - Eric Littman
- School of Veterinary Medicine, University of California-Davis, Davis, California, USA
| | - Khalid Shahin
- School of Veterinary Medicine, University of California-Davis, Davis, California, USA
- Aquatic Animals Diseases Laboratory, National Institute of Oceanography and Fisheries, Suez, Egypt
| | - Taylor I Heckman
- School of Veterinary Medicine, University of California-Davis, Davis, California, USA
| | | | - Diem Thu Nguyen
- School of Veterinary Medicine, University of California-Davis, Davis, California, USA
| | - Ruixue Hu
- School of Veterinary Medicine, University of California-Davis, Davis, California, USA
| | - Mark Adkison
- California Department of Fish and Wildlife, Rancho Cordova, California, USA
| | - Tresa Veek
- California Department of Fish and Wildlife, Rancho Cordova, California, USA
| | - Kavery Mukkatira
- California Department of Fish and Wildlife, Rancho Cordova, California, USA
| | - Christine Richey
- California Department of Fish and Wildlife, Rancho Cordova, California, USA
| | - Kevin Kwak
- California Department of Fish and Wildlife, Rancho Cordova, California, USA
| | - Haitham H Mohammed
- Department of Rangeland, Wildlife and Fisheries Management, College of Agriculture and Life Sciences, Texas A&M University, College Station, Texas, USA
| | - Cesar Ortega
- Centro de Investigación y Estudios Avanzados en Salud Animal, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma del Estado de México, Toluca, Mexico
| | - Ruben Avendaño-Herrera
- Laboratorio de Patología de Organismos Acuáticos y Biotecnología Acuícola, Facultad de Ciencias de la Vida, Universidad Andrés Bello and Fondo de Financiamiento de Centros de Investigación en Áreas Prioritarias, Centro Interdisciplinario de Investigación en Acuicultura Sustentable, Viña del Mar, Chile
| | | | | | - Ian Gardner
- Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island, Canada
| | - Timothy J Welch
- U.S. Department of Agriculture, Agricultural Research Service, National Center for Cool and Coldwater Aquaculture, Leetown, West Virginia, USA
| | - Esteban Soto
- School of Veterinary Medicine, University of California-Davis, Davis, California, USA
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Ballantyne R, Lee JW, Liu CH. First identification and histopathological analysis of Lactococcus garvieae infection in whiteleg shrimp, Penaeus vannamei cultured in low salinity water. JOURNAL OF FISH DISEASES 2023; 46:929-942. [PMID: 37309584 DOI: 10.1111/jfd.13814] [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: 03/16/2023] [Revised: 05/13/2023] [Accepted: 05/17/2023] [Indexed: 06/14/2023]
Abstract
The isolation and characterization of bacterial species Lactococcus garvieae, previously unreported in whiteleg shrimp, Penaeus vannamei, has now been identified in the species. The pathogen was recovered from an affected shrimp farm in southern Taiwan. Bacterial characterization first identified the isolate as Gram-positive cocci, and biochemical profiles demonstrated that the causative agent of mortality was 97% L. garvieae. The bacterial cell DNA resulted in amplification of 1522 bp with 99.6% confirmation by PCR analysis. The phylogenetic tree revealed 100% evolutionary similarity among previously isolated strains. Experimental infection further confirmed higher susceptibility of whiteleg shrimp to L. garvieae in waters of lower salinity, particularly 5 ppt, than in higher salinity. Histopathological analysis showed severely damaged hepatopancreas with necrotized, elongated, collapsed tubules, dislodged membranes and granuloma formation in infected shrimp. Transmission electron microscopy observation indicated a hyaluronic acid capsular layer surrounding bacterial cell which is a virulence factor of L. garvieae and likely responsible for immunosuppression and higher mortality of shrimp cultured in lower salinity. Collectively, these findings report the first isolation of L. garvieae from whiteleg shrimp and shed new light on the disease that threatens the highly valuable species and accentuates the need for finding a solution.
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Affiliation(s)
- Rolissa Ballantyne
- Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Jai-Wei Lee
- Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Chun-Hung Liu
- Department of Aquaculture, National Pingtung University of Science and Technology, Pingtung, Taiwan
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de Ruyter T, Littman E, Yazdi Z, Adkison M, Camus A, Yun S, Welch TJ, Keleher WR, Soto E. Comparative Evaluation of Booster Vaccine Efficacy by Intracoelomic Injection and Immersion with a Whole-Cell Killed Vaccine against Lactococcus petauri Infection in Rainbow Trout ( Oncorhynchus mykiss). Pathogens 2023; 12:pathogens12050632. [PMID: 37242302 DOI: 10.3390/pathogens12050632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 04/07/2023] [Accepted: 04/08/2023] [Indexed: 05/28/2023] Open
Abstract
Lactococcus petauri is an important emergent bacterial pathogen of salmonids in the USA. The purpose of this study was to evaluate the protection conferred to rainbow trout (Oncorhynchus mykiss) against L. petauri by formalin-killed vaccines in immersion and injectable forms, as well as the enhanced protection afforded by booster vaccination. In the first challenge, fish were immunized via intracoelomic injection (IC) or immersion (Imm) routes alone. Approximately 418 degree days (Temperature in degree Celsius × days post-immunization) (dd) Imm, or 622 dd IC post-vaccination, fish were challenged via IC with wild-type L. petauri. In the second experiment, initial Imm vaccination was followed by booster vaccination via Imm or IC routes 273 dd post-immunization along with appropriate PBS controls. The various vaccination protocol efficacies were evaluated by challenging fish with L. petauri by cohabitation with diseased fish 399 dd post-booster administration. A relative percent survival (RPS) of 89.5% and 28% was recorded in the IC and Imm single immunization treatments, respectively. In the second study, an RPS of 97.5%, 10.2%, 2.6% and -10.1% plus approximately 0%, 50%, 20%, and 30% bacterial persistence was recorded in the Imm immunized + IC boosted, Imm immunized + mock IC boosted, Imm immunized + Imm boosted, and Imm immunized + mock Imm boosted treatments, respectively. Only the Imm immunized + IC injection boosted treatments provided significant protection when compared to unvaccinated and challenged treatments (p < 0.05). In conclusion, although both Imm and IC vaccines appear safe for trout, the inactivated Imm vaccines seem to provide only mild and temporary protection against lactococcosis; whereas IC immunized trout develop a significantly stronger protective response in both challenges.
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Affiliation(s)
- Tryssa de Ruyter
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
- School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Eric Littman
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
| | - Zeinab Yazdi
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
| | - Mark Adkison
- California Department of Fish and Wildlife, Rancho Cordova, CA 95670, USA
| | - Alvin Camus
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Susan Yun
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
| | - Timothy J Welch
- National Center for Cool and Coldwater Aquaculture, Kearneysville, WV 25430, USA
| | | | - Esteban Soto
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
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Design of Lactococcus lactis Strains Producing Garvicin A and/or Garvicin Q, Either Alone or Together with Nisin A or Nisin Z and High Antimicrobial Activity against Lactococcus garvieae. Foods 2023; 12:foods12051063. [PMID: 36900581 PMCID: PMC10000435 DOI: 10.3390/foods12051063] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 02/20/2023] [Accepted: 02/24/2023] [Indexed: 03/06/2023] Open
Abstract
Lactococcus garvieae is a main ichthyopathogen in rainbow trout (Oncorhynchus mykiss, Walbaum) farming, although bacteriocinogenic L. garvieae with antimicrobial activity against virulent strains of this species have also been identified. Some of the bacteriocins characterized, such as garvicin A (GarA) and garvicin Q (GarQ), may show potential for the control of the virulent L. garvieae in food, feed and other biotechnological applications. In this study, we report on the design of Lactococcus lactis strains that produce the bacteriocins GarA and/or GarQ, either alone or together with nisin A (NisA) or nisin Z (NisZ). Synthetic genes encoding the signal peptide of the lactococcal protein Usp45 (SPusp45), fused to mature GarA (lgnA) and/or mature GarQ (garQ) and their associated immunity genes (lgnI and garI, respectively), were cloned into the protein expression vectors pMG36c, which contains the P32 constitutive promoter, and pNZ8048c, which contains the inducible PnisA promoter. The transformation of recombinant vectors into lactococcal cells allowed for the production of GarA and/or GarQ by L. lactis subsp. cremoris NZ9000 and their co-production with NisA by Lactococcus lactis subsp. lactis DPC5598 and L. lactis subsp. lactis BB24. The strains L. lactis subsp. cremoris WA2-67 (pJFQI), a producer of GarQ and NisZ, and L. lactis subsp. cremoris WA2-67 (pJFQIAI), a producer of GarA, GarQ and NisZ, demonstrated the highest antimicrobial activity (5.1- to 10.7-fold and 17.3- to 68.2-fold, respectively) against virulent L. garvieae strains.
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Altinok I, Ozturk RC, Ture M. NGS analysis revealed that Lactococcus garvieae Lg-Per was Lactococcus petauri in Türkiye. JOURNAL OF FISH DISEASES 2022; 45:1839-1843. [PMID: 36349908 DOI: 10.1111/jfd.13708] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 07/29/2022] [Accepted: 08/02/2022] [Indexed: 06/16/2023]
Abstract
Lactococcus garvieae Lg-per was originally isolated from rainbow trout cultured in cages located on the Turkish coast of the Black Sea in 2011. A whole genome sequence of Lg-per was performed in the present study. The complete genome of Lg-per mapped to the reference genomes of L. garvieae (GCF_000269925.1) and Lactococcus petauri (GCF_014830225.1) had a total of 1,694,407 and 1,945,297 base pairs, respectively. Lg-per had 1955 protein-coding genes and 4 rRNA, 46 tRNA and 1 tmRNA operons. The orthoANI value was 98.30% between Lg-per and L. petauri (GCF_014830225.1) and 93.1% between Lg-per and L. garvieae (GCF_000269925.1). A phylogenetic tree generated from the whole genome sequences (WGS) of several Lactococcus species found that L. petauri (GCA 002154895) was closely related to the Lg-per strain with 98% similarity. Although L. garvieae Lg-per was confirmed as L. garvieae based on phenotypical, biochemical and 16S rRNA sequence, WGS of the Lg-per strain revealed that Lg-per was L. petauri. Using a 16S rRNA-based PCR detection approach, Lg-per was misdiagnosed as L. garvieae since its 16S rRNA gene was 99.9% similar to that of L. garvieae strains. Consequently, the 16S rRNA-based PCR detection approach may not be adequate for the identification of the Lactococcus genus. This is the first study to document the presence of L. petauri in Türkiye. L. garvieae isolates should be analysed using WGS since the same issue might occur in other countries.
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Affiliation(s)
- Ilhan Altinok
- Department of Fisheries Technology Engineering, Faculty of Marine Sciences, Karadeniz Technical University, Trabzon, Turkiye
| | - Rafet Cagri Ozturk
- Department of Fisheries Technology Engineering, Faculty of Marine Sciences, Karadeniz Technical University, Trabzon, Turkiye
| | - Mustafa Ture
- Fish Health Department, Central Fisheries Research Institute, Trabzon, Turkiye
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10
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Feito J, Araújo C, Gómez-Sala B, Contente D, Campanero C, Arbulu S, Saralegui C, Peña N, Muñoz-Atienza E, Borrero J, del Campo R, Hernández PE, Cintas LM. Antimicrobial activity, molecular typing and in vitro safety assessment of Lactococcus garvieae isolates from healthy cultured rainbow trout (Oncorhynchus mykiss, Walbaum) and rearing environment. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113496] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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11
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Shahin K, Mukkatira K, Yazdi Z, Richey C, Kwak K, Heckman TI, Mohammed HH, Ortega C, Avendaño-Herrera R, Keleher B, Hyatt MW, Drennan JD, Adkison M, Griffin MJ, Soto E. Development of a quantitative polymerase chain reaction assay for detection of the aetiological agents of piscine lactococcosis. JOURNAL OF FISH DISEASES 2022; 45:847-859. [PMID: 35306674 DOI: 10.1111/jfd.13610] [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: 11/15/2021] [Revised: 03/01/2022] [Accepted: 03/04/2022] [Indexed: 06/14/2023]
Abstract
Piscine lactococcosis is an emergent bacterial disease that is associated with high economic losses in many farmed and wild aquatic species worldwide. Early and accurate detection of the causative agent of piscine lactococcosis is essential for management of the disease in fish farms. In this study, a TaqMan quantitative polymerase chain reaction (qPCR) targeting the 16S-23S rRNA internal transcribed spacer region was developed and validated. Validation of the qPCR was performed with DNA of previously typed L. petauri and L. garvieae recovered from different aquatic hosts from distinct geographical locations, closely related bacterial species and common pathogens in trout aquaculture. Further diagnostic sensitivity and specificity was investigated by screening of fish, water and faecal samples. The developed qPCR assay showed high specificity, sensitivity and accuracy in detection of L. petauri and L. garvieae with lack of signals from non-target pathogens, and in screening of rainbow trout (Oncorhynchus mykiss) posterior kidney and environmental samples. The detection limit of the qPCR was four amplicon copies. Moreover, the sensitivity of the qPCR assay was not affected by presence of non-target DNA from either fish or environmental samples. The robustness, specificity and sensitivity of the developed qPCR will facilitate fast and accurate diagnosis of piscine lactococcosis to establish appropriate control measures in fish farms and aquaria.
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Affiliation(s)
- Khalid Shahin
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
- Aquatic Animal Diseases Laboratory, Aquaculture Department, National Institute of Oceanography and Fisheries, Suez, Egypt
| | | | - Zeinab Yazdi
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Christine Richey
- California Department of Fish and Wildlife, Rancho Cordova, California, USA
| | - Kevin Kwak
- California Department of Fish and Wildlife, Rancho Cordova, California, USA
| | - Taylor I Heckman
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Haitham H Mohammed
- Department of Aquatic Animal Medicine and Management, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt
| | - Cesar Ortega
- Centro de Investigación y Estudios Avanzados en Salud Animal (CIESA), Facultad de Medicina Veterinaria y Zootecnia (FMVZ), Universidad Autónoma del Estado de México (UAEM), Toluca, Mexico
| | - Ruben Avendaño-Herrera
- Laboratorio de Patología de Organismos Acuáticos y Biotecnología Acuícola, Universidad Andrés Bello and Centro FONDAP INCAR, Viña del Mar, Chile
| | - Bill Keleher
- Kennebec River Biosciences, Richmond, Maine, USA
| | - Michael W Hyatt
- Wildlife Conservation Society, New York Aquarium, Brooklyn, New York, USA
| | | | - Mark Adkison
- California Department of Fish and Wildlife, Rancho Cordova, California, USA
| | - Matt J Griffin
- Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, Mississippi, USA
| | - Esteban Soto
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
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12
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Swaminathan TR, Nithyanantham SR, Narendrakumar L, Dharmaratnam A, Sood N, Pradhan PK, Sulumane Ramachandra KS, Lal KK. Co-infection of Lactococcus garvieae and Tilapia lake virus (TiLV) in Nile tilapia Oreochromis niloticus cultured in India. DISEASES OF AQUATIC ORGANISMS 2021; 147:127-140. [PMID: 34913441 DOI: 10.3354/dao03638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Tilapia lake virus (TiLV) and Lactococcus garvieae are 2 major pathogens of cultured Nile tilapia Oreochromis niloticus. In June-July 2018, a disease outbreak was reported in Nile tilapia cultured in brackish water floating cages in Kerala, India. Affected fish died gradually, and cumulative mortality reached ~75% within 1 mo. In the present study, TiLV and L. garvieae were isolated from the infected fish and confirmed. Nucleotide analysis of the partial sequence of segment 3 revealed that the present TiLV isolate showed 100% similarity with TiLV MF574205 and 97.65% similarity with TiLV KU552135 isolated in Israel. The partial 16S rDNA nucleotide sequence of L. garvieae shared 99% similarity with the 16S rDNA nucleotide sequence of L. garvieae isolated from Nile tilapia in Brazil. Eight virulence genes (hly1, hly2, hly3, NADH oxidase, adhPav, LPxTG-1, LPxTG-4, adhC1) were amplified in the present isolate. In the experimental challenge study, the onset of mortality started earlier in fish co-infected with TiLV and L. garvieae (3 d post-infection [dpi]) compared to other groups. Cumulative mortality (90% at 12 dpi) was significantly higher in the co-infected group than in fish infected with TiLV (60% at 12 dpi) and L. garvieae (40% at 12 dpi) alone. This study reveals that synergistic co-infection with TiLV and other bacteria may increase mortality in disease outbreaks. To the best of our knowledge, this is the first reported co-infection of L. garvieae with TiLV associated with mass mortality in Nile tilapia in India.
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Affiliation(s)
- Thangaraj Raja Swaminathan
- Peninsular and Marine Fish Genetic Resources Centre, ICAR National Bureau of Fish Genetic Resources, CMFRI Campus, Kochi, Kerala 682 018, India
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13
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Harikrishnan R, Devi G, Van Doan H, Balamurugan P, Arockiaraj J, Balasundaram C. Hepatic antioxidant activity, immunomodulation, and pro-anti-inflammatory cytokines manipulation of κ-carrageenan (κ-CGN) in cobia, Rachycentron canadum against Lactococcus garvieae. FISH & SHELLFISH IMMUNOLOGY 2021; 119:128-144. [PMID: 34562582 DOI: 10.1016/j.fsi.2021.09.024] [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: 08/14/2021] [Revised: 09/20/2021] [Accepted: 09/21/2021] [Indexed: 06/13/2023]
Abstract
The effects of dietary k-Carrageenan (k-CGN) at 10, 20, and 30 g kg-1 on growth rate, hemato-biochemical indices, innate-adaptive parameters and modification of pro- and/or anti-inflammatory cytokines and chemokines pathway in cobia, Rachycentron canadum against Lactococcus garvieae is reported. The weight gain (WG) increased substantially (P < 0.05) in all k-CGN treated groups; the specific growth rate (SGR) was significant in healthy uninfected normal (HuN) and L. garvieae challenged (LaC) groups fed with 20 g kg-1k-CGN diet on 45 and 60 days. The white blood cell (WBC) counts, total protein (TP) level, total anti-oxidant (T-AOC), catalase (CAT), and glutathione (GSH) activities increased significantly when fed with 20 g and 30 g kg-1k-CG diets on 45th and 60th day. The immunological parameters such as phagocytic (PC) index and the activity of phagocytic (PC), respiratory burst (RB), superoxide dismutase (SOD), alternate complement pathway (ACH50), and lysozyme (LZM) were significantly enhanced with all k-CG diets in 45 and 60 days of treatment. No cumulative mortality (CM) in HuN group fed by control or any k-CGN diets. CM was 5% in LaC group fed with 20 g kg-1k-CGN diet whereas in LaC groups fed with 10 g and 30 g kg-1k-CGN diets the CM was 10%. The interleukin 1 beta (IL-1β) and tumor necrosis factor alpha (TNFα) pro-inflammatory cytokines mRNA transcripts were one-fold high (P < 0.05) in both HuN and LaC group fed all k-CGN enriched diets on 45 and 60 days. Similarly, IL-18 and TLR2 mRNA was one-fold high expression in both groups fed the 20 g and 30 g kg-1k-CGN enriched diets on 45 or 60 days. Interferon gamma (IFNγ) and interferon regulatory factor 3/7 (IRF3/IRF7) mRNA transcripts did not change with any diet. IL-6, IL-10, and IL-11 mRNA were one-fold high expressions in both groups fed the 20 g and 30 g kg-1k-CGN enriched diets on 45 and 60 days. However, the expression of CC1, CC3, and CCR9 pro-inflammatory chemokines mRNA did not vary with any control or k-CGN enriched diets. The results indicate that diet enriched with k-CGN at 20 g kg-1 significantly influences the growth, antioxidant and innate-adaptive immune performance, and pro-anti-inflammatory cytokines and chemokines regulation in cobia against L. garvieae.
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Affiliation(s)
- Ramasamy Harikrishnan
- Department of Zoology, Pachaiyappa's College for Men, Kanchipuram, 631 501, Tamil Nadu, India
| | - Gunapathy Devi
- Department of Zoology, Nehru Memorial College, Puthanampatti, 621 007, Tamil Nadu, India
| | - Hien Van Doan
- Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai, 50200, Thailand; Science and Technology Research Institute, Chiang Mai University, 239 Huay Keaw Rd., Suthep, Muang, Chiang Mai, 50200, Thailand.
| | - Paramaraj Balamurugan
- Department of Biotechnology, St. Michael College of Engineering and Technology, Kalayarkoil, 630 551, Tamil Nadu, India
| | - Jesu Arockiaraj
- SRM Research Institute, SRM Institute of Science and Technology, Kattankulathur, 603 203, Chennai, Tamil Nadu, India; Department of Biotechnology, College of Science and Humanities, SRM Institute of Science and Technology, Kattankulathur, 603 203, Chennai, Tamil Nadu, India
| | - Chellam Balasundaram
- Department of Herbal and Environmental Science, Tamil University, Thanjavur, 613 005, Tamil Nadu, India
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14
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Park SH, Lee YH, Yeo MH, Chang KS. First Case of Urinary Tract Infection by Lactococcus garvieae in Korea. KOREAN JOURNAL OF CLINICAL LABORATORY SCIENCE 2021. [DOI: 10.15324/kjcls.2021.53.3.277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Sang-Hyun Park
- Department of Clinical Laboratory Science, Catholic University of Pusan, Busan, Korea
| | - Young-Hyeon Lee
- Department of Clinical Laboratory Science, Catholic University of Pusan, Busan, Korea
| | - Min-Ho Yeo
- Department of Clinical Laboratory Science, Catholic University of Pusan, Busan, Korea
| | - Kyung-Soo Chang
- Department of Clinical Laboratory Science, Catholic University of Pusan, Busan, Korea
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15
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Soltani M, Baldisserotto B, Hosseini Shekarabi SP, Shafiei S, Bashiri M. Lactococcosis a Re-Emerging Disease in Aquaculture: Disease Significant and Phytotherapy. Vet Sci 2021; 8:vetsci8090181. [PMID: 34564575 PMCID: PMC8473265 DOI: 10.3390/vetsci8090181] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/25/2021] [Accepted: 08/30/2021] [Indexed: 11/17/2022] Open
Abstract
Lactococcosis, particularly that caused by Lactococcus garvieae, is a major re-emerging bacterial disease seriously affecting the sustainability of aquaculture industry. Medicinal herbs and plants do not have very much in vitro antagonism and in vivo disease resistance towards lactococcosis agents in aquaculture. Most in vitro studies with herbal extractives were performed against L. garvieae with no strong antibacterial activity, but essential oils, especially those that contain thymol or carvacrol, are more effective. The differences exhibited by the bacteriostatic and bactericidal functions for a specific extractive in different studies could be due to different bacterial strains or parts of chemotypes of the same plant. Despite essential oils being shown to have the best anti-L. garvieae activity in in vitro assays, the in vivo bioassays required further study. The extracts tested under in vivo conditions presented moderate efficacy, causing a decrease in mortality in infected animals, probably because they improved immune parameters before challenging tests. This review addressed the efficacy of medicinal herbs to lactococcosis and discussed the presented gaps.
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Affiliation(s)
- Mehdi Soltani
- Freshwater Fish Group and Fish Health Unit, Centre for Sustainable Aquatic Ecosystems, Harry Butler Institute, Murdoch University, Murdoch, Perth, WA 6150, Australia
- Department of Aquatic Animal Health, Faculty of Veterinary Medicine, University of Tehran, Tehran 1419963111, Iran;
- Correspondence: or
| | - Bernardo Baldisserotto
- Department of Physiology and Pharmacology, Federal University of Santa Maria, Santa Maria 97105-900, RS, Brazil;
| | | | - Shafigh Shafiei
- Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, Shahrekord University, Shahrekord 64165478, Iran;
| | - Masoumeh Bashiri
- Department of Aquatic Animal Health, Faculty of Veterinary Medicine, University of Tehran, Tehran 1419963111, Iran;
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16
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Shahin K, Veek T, Heckman TI, Littman E, Mukkatira K, Adkison M, Welch TJ, Imai DM, Pastenkos G, Camus A, Soto E. Isolation and characterization of Lactococcus garvieae from rainbow trout, Onchorhyncus mykiss, from California, USA. Transbound Emerg Dis 2021; 69:2326-2343. [PMID: 34328271 DOI: 10.1111/tbed.14250] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 07/17/2021] [Indexed: 11/26/2022]
Abstract
Lactococcus garvieae is an emergent bacterial pathogen of salmonid fish in North America that causes acute infections particularly at water temperatures above 15°C. During 2020, L. garvieae was detected in rainbow trout, Onchorhyncus mykiss, cultured in Southern California and the Eastern Sierras. Infected fish exhibited high mortalities and nonspecific clinical signs of lethargy, erratic swimming, dark skin pigmentation, and exophthalmia. Macroscopic changes included external and internal hemorrhages, mainly in the eyes, liver, coelomic fat, intestine, and brain. Histological examination revealed splenitis, branchitis, panophthalmitis, hepatitis, enteritis, and coelomitis, with variable degrees of tissue damage among evaluated fish. Pure colonies of L. garvieae were isolated from infected trout and specific PCR primers for L. garvieae confirmed the preliminary diagnosis. Multilocus sequence analysis showed that the strains recovered from diseased trout represent a novel genetic group. Isolates were able to form biofilms within 24 h that increased their resistance to disinfection by hydrogen peroxide. Laboratory challenge methods for inducing lactococcosis in steelhead trout, O. mykiss, were evaluated by intracoelomic injection with serial dilutions of L. garvieae. The median lethal dose 21 days post challenge was ∼20 colony-forming units/fish. Experimentally infected trout presented similar clinical signs, gross changes, and microscopic lesions as those with natural disease, fulfilling Koch's postulates and demonstrating the high virulence of the recovered strains.
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Affiliation(s)
- Khalid Shahin
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA.,Aquatic Animal Diseases Laboratory, Aquaculture Department, National Institute of Oceanography and Fisheries, Suez, Egypt
| | - Tresa Veek
- California Department of Fish and Wildlife, Rancho Cordova, California, USA
| | - Taylor I Heckman
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Eric Littman
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
| | | | - Mark Adkison
- California Department of Fish and Wildlife, Rancho Cordova, California, USA
| | - Timothy J Welch
- National Center for Cool and Coldwater Aquaculture, Kearneysville, West Virginia, USA
| | - Denise M Imai
- Comparative Pathology Laboratory, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Gabrielle Pastenkos
- Comparative Pathology Laboratory, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Alvin Camus
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Esteban Soto
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
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