An Acute Viral Disease of Channel Catfish

An Acute Viral Disease of Channel Catfish

Author: Nilola N. Fijan

Publisher:

Published: 1970

Total Pages: 16

ISBN-13:

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In epizootics of channel catfish virus diseasse (CCVD) at four widely separated fish farms in 1968, affected fry and fingerlings spiraled, hung in a vertical position with head at the surface, or were distressed. In various combinations were edema, hemorrages, and anemia. The disease had a peracute to acute course, and stress to the fish preceded most epizootics. The virus induced formation of syncytial cells in affected cultures, which is considered at present to be of diagnostic significance. Secondary bacterial infections were found in fish with CCVD. Columnaris infection masked the symptoms of the virus disease.


Emerging Viral Diseases of Southeast Asia

Emerging Viral Diseases of Southeast Asia

Author: Sunil K. Lal

Publisher: Karger Medical and Scientific Publishers

Published: 2007

Total Pages: 322

ISBN-13: 3805581750

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Experts discuss the threat posed by emerging viruses and describe ongoing efforts to face future outbreaks by searching for new antivirals, developing new vaccines, and improving methods of diagnosis and surveillance. Australian contributor.


Fish Viruses and Fish Viral Diseases

Fish Viruses and Fish Viral Diseases

Author: Ken Wolf

Publisher: Cornell University Press

Published: 2019-05-15

Total Pages: 491

ISBN-13: 1501746383

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This book is a comprehensive, generously illustrated, and up-to-date reference on the virology of fishes—predomiantly species of the class Osteichthyes, but including representative members of the classes Chrondrichthyes and Myxini. It covers some thirty years since the first virus was isolated from a fish and describes 63 diseases and agents of viral, viruslike, or mistaken viral nature.


Evolution and Epidemiology of Channel Catfish Virus (CCV)

Evolution and Epidemiology of Channel Catfish Virus (CCV)

Author: Arun Venugopalan

Publisher:

Published: 2023

Total Pages: 0

ISBN-13:

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Channel catfish virus disease (CCVD) is the principal viral disease in the United States catfish industry. The CCVD is caused by channel catfish virus (CCV), with mortality reaching up to 100% in fingerlings. CCV is assigned taxonomically to the family Alloherpesviridae, genus Ictalurivirus, species Ictalurid herpesvirus 1 (IcHV-1). To date, virulence, immunogenicity, and genome plasticity of the CCV field isolates have not been investigated. Three genotypes of CCV (IcHV-1A, IcHV-1B, and BCAHV) were identified using restriction fragment length polymorphism (RFLP) analysis. Virulence assessment of three representative isolates of RFLP groups suggests that IcHV-1B (pooled survival [mean ℗ł SE]: 58.3% ℗ł 2.6) showed significantly lower survival than IcHV-1A (68.6% ℗ł 2.4). Re-exposure of the survivors with a representative of IcHV-1A and IcHV-1B isolates indicates a robust cross-protective effect (relative percent survival [RPS]: 80-100%). Antigenic determinants against anti-CCV monoclonal antibody Mab-95 were conserved among IcHV-1A, and IcHV-1B; however, BCAHV possesses antigenically distinct epitopes (Neutralization index [NI] = 0). Although BCAHV and CCV have nearly colinear genomes (except for the absence of ORF16A in CCV), they represent distinct species, given that nucleotide identity is 93.9%. Moreover, infectivity trials indicated that channel and hybrid catfish fingerlings might be refractive to LD50 (1.3©7105 TCID50/L) dosage of BCAHV. However, previous exposure to BCAHV has protected the channel and hybrid catfish against the subsequent infection with the ATCC strain of CCV (RPS:100%). Next, two discriminatory duplex probe-based qPCR assays were designed and validated to diagnose latent IcHV-1A and IcHV-1B. Spatio-temporal survey of six Mississippi catfish hatcheries indicated that the prevalence of latent CCV genotypes varied between 25-100%. Lastly, twenty one reference quality genomes of CCV field isolates were assembled, and phylogenomic analyses supported the monophyly of the CCV field isolates with BCAHV as their closest relative. The phylogenomic analyses confirmed the two distinct genotypes (IcHV-1A and IcHV-1B) identified in RFLP analysis and further allowed the segregation of the IcHV-1A genotype into two subgroups, IcHV-1A1 and IcHV-1A2. Results from the current studies lay the foundation for future research and will help formulate efficient management strategies to reduce the economic impact of CCV in the catfish industry.