Complete genome of isolate K2014767 from the hepatopancreas of captive Caribbean spiny lobster ().

The complete genome sequence is reported for isolate K2014767, isolated from a captive Caribbean spiny lobster () during a species-specific mortality event in a public display aquarium in the United States.

Redefining piscine lactococcosis.

Unlabelled: 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 .

Pathology, microbiology, and genetic diversity associated with and novel spp. infections in southern sea otters ().

spp., including , are zoonotic bacterial pathogens that can cause morbidity and mortality in mammals, fish, reptiles, birds, and humans. The southern sea otter (SSO; ) is a federally-listed threatened species for which infectious disease is a major cause of mortality.

Acipenserid herpesvirus 2 genome and partial validation of a qPCR for its detection in white sturgeon Acipenser transmontanus.

White sturgeon Acipenser transmontanus is the primary species used for caviar and sturgeon meat production in the USA. An important pathogen of white sturgeon is acipenserid herpesvirus 2 (AciHV-2). In this study, 4 archived isolates from temporally discrete natural outbreaks spanning the past 30 yr were sequenced via Illumina and Oxford Nanopore Technologies platforms.

Influence of probiotic and prebiotic supplementation on intestinal microbiota and resistance to Edwardsiella ictaluri infection in channel catfish (Ictalurus punctatus) following florfenicol administration.

Enteric septicemia of catfish (ESC), caused by the gram-negative enteric bacteria Edwardsiella ictaluri, is a significant threat to catfish aquaculture in the southeastern United States. Antibiotic intervention can reduce mortality; however, antibiotic use results in an imbalance, or dysbiosis, of the gut microbiota, which may increase susceptibility of otherwise healthy fish to enteric infections. Herein, recovery of the intestinal microbiota and survivability of channel catfish in response to ESC challenge was evaluated following a 10-day course of florfenicol and subsequent probiotic or prebiotic supplementation.

The generation of the first chromosome-level de novo genome assembly and the development and validation of a 50K SNP array for the St. John River aquaculture strain of North American Atlantic salmon.

Atlantic salmon (Salmo salar) in Northeastern US and Eastern Canada has high economic value for the sport fishing and aquaculture industries. Large differences exist between the genomes of Atlantic salmon of European origin and North American (N.A.

Reference genomes of channel catfish and blue catfish reveal multiple pericentric chromosome inversions.

Background: Channel catfish and blue catfish are the most important aquacultured species in the USA. The species do not readily intermate naturally but F hybrids can be produced through artificial spawning. F hybrids produced by mating channel catfish female with blue catfish male exhibit heterosis and provide an ideal system to study reproductive isolation and hybrid vigor.

First Isolation of a Herpesvirus (Family ) from Great Lakes Lake Sturgeon ().

The lake sturgeon (Acipenser fulvescens; LST) is the only native sturgeon species in the Great Lakes (GL), but due to multiple factors, their current populations are estimated to be <1% of historical abundances. Little is known about infectious diseases affecting GL-LST in hatchery and wild settings. Therefore, a two-year disease surveillance study was undertaken, resulting in the detection and first in vitro isolation of a herpesvirus from grossly apparent cutaneous lesions in wild adult LST inhabiting two GL watersheds (Erie and Huron).

MYXOZOAN COMMUNITY COMPOSITION AND DIVERSITY IN CLINICAL CASES OF PROLIFERATIVE GILL DISEASE IN MISSISSIPPI CATFISH AQUACULTURE.

An abundance of morphologically variable Henneguya species complicates the understanding of disease relationships between ictalurid catfish and myxozoan (Phylum: Cnidaria) parasites on North American aquaculture operations. Henneguya ictaluri, the cause of proliferative gill disease (PGD) in channel and hybrid catfish, is arguably the most important parasite of commercial catfish aquaculture in the southeastern United States. While research indicates arrested development and limited sporogenesis of H.

New data on Henneguya postexilis Minchew, 1977, a parasite of channel catfish Ictalurus punctatus, with notes on resolution of molecular markers for myxozoan phylogeny.

Previous morphological and histological data are supplemented with molecular and ultrastructural data for a Henneguya sp. isolated from farm-raised channel catfish Ictalurus punctatus in Mississippi, USA. Myxospores were cryptic, encapsulated within a thin layer of epithelium in the gill lamellae with spore measurements consistent with the original description of Henneguya postexilis Minchew, 1977.

The fish pathogen Flavobacterium columnare represents four distinct species: Flavobacterium columnare, Flavobacterium covae sp. nov., Flavobacterium davisii sp. nov. and Flavobacterium oreochromis sp. nov., and emended description of Flavobacterium columnare.

Flavobacterium columnare is the causative agent of columnaris disease in freshwater fish and four discrete genetic groups exist within the species, suggesting that the species designation requires revision. The present study determined the taxonomic status of the four genetic groups of F. columnare using polyphasic and phylogenomic approaches and included five representative isolates from each genetic group (including type strain ATCC 23463; genetic group 1).

Complete Genome Sequences of Francisella marina Strains E95-16 and E103-15, Isolated from Maricultured Spotted Rose Snapper () on the Pacific Coast of Central America.

In 2015 and 2016, a previously unrecognized sp. was isolated from disease outbreaks in maricultured spotted rose snapper () on the Pacific coast of Central America. Polyphasic analysis demonstrated these bacteria differed from any known spp.

A long reads-based de-novo assembly of the genome of the Arlee homozygous line reveals chromosomal rearrangements in rainbow trout.

Currently, there is still a need to improve the contiguity of the rainbow trout reference genome and to use multiple genetic backgrounds that will represent the genetic diversity of this species. The Arlee doubled haploid line was originated from a domesticated hatchery strain that was originally collected from the northern California coast. The Canu pipeline was used to generate the Arlee line genome de-novo assembly from high coverage PacBio long-reads sequence data.

Characterization of a Novel Conjugative Plasmid in Strain MS-18-199.

is a pathogenic bacterium responsible for significant losses in important wild and cultured fish species. strain MS-18-199 recovered from a diseased hybrid catfish from East Mississippi and showed resistance to florfenicol, chloramphenicol, oxytetracycline, doxycycline, erythromycin, tetracycline, azitromycin, spectinomycin, sulfonamide, and bacitracin. To explore the mechanisms of resistance in strain MS-18-199, genomic DNA was extracted and subjected to whole genome sequencing (WGS) using a combination of long (Oxford Nanopore) and short (Illumina) reads.

Description of sp. nov., an emergent fish pathogen, and assessment of virulence using a tiger barb () infection model.

A recently described emergent disease of ornamental fish has been associated with an species positive for the surface protective antigen () C gene. Whole genome sequencing was performed on five isolates from diseased ornamental fish. In addition, these isolates were compared to and other -positive species isolated from terrestrial and marine mammals, birds and fish using multi-locus sequence analysis (MLSA).

Complete genome sequence data of multidrug-resistant strain MS-18-37.

are Gram-negative, non-spore forming rods belonging to the family within the class . These facultative anaerobic bacteria are ubiquitous in aquatic environments and have a broad host range. We present here the complete genome sequence of multidrug-resistant strain MS-18-37 isolated from diseased catfish.

The Y chromosome sequence of the channel catfish suggests novel sex determination mechanisms in teleost fish.

Background: Sex determination mechanisms in teleost fish broadly differ from mammals and birds, with sex chromosomes that are far less differentiated and recombination often occurring along the length of the X and Y chromosomes, posing major challenges for the identification of specific sex determination genes. Here, we take an innovative approach of comparative genome analysis of the genomic sequences of the X chromosome and newly sequenced Y chromosome in the channel catfish.

Results: Using a YY channel catfish as the sequencing template, we generated, assembled, and annotated the Y genome sequence of channel catfish.

Development of genomic predictions for harvest and carcass weight in channel catfish.

Background: Catfish farming is the largest segment of US aquaculture and research is ongoing to improve production efficiency, including genetic selection programs to improve economically important traits. The objectives of this study were to investigate the use of genomic selection to improve breeding value accuracy and to identify major single nucleotide polymorphisms (SNPs) associated with harvest weight and residual carcass weight in a channel catfish population. Phenotypes were available for harvest weight (n = 27,160) and residual carcass weight (n = 6020), and 36,365 pedigree records were available.

The proliferation and clonal migration of B cells in the systemic and mucosal tissues of channel catfish suggests there is an interconnected mucosal immune system.

IgM transcripts from different mucosal and systemic tissues from a single adult channel catfish have been evaluated. Arrayed heavy chain cDNA libraries from each of these different mucosal and systemic tissues were separately constructed, hybridized with VH family specific probes and a variety of approaches were used to define their structural relationships. Baseline hybridization studies indicated that the tissue libraries had different VH expression patterns, and sequencing studies indicated this was not simply due to varying proportions of the same B cell population.

Draft Genome Sequence of Fish Pathogen Aeromonas bestiarum GA97-22.

is a Gram-negative mesophilic motile bacterium causing acute hemorrhagic septicemia or chronic skin ulcers in fish. Here, we report the draft genome sequence of strain GA97-22, which was isolated from rainbow trout in 1997. This genome sequence will improve our understanding of the complex taxonomy of motile aeromonads.

Comparison of Channel Catfish and Blue Catfish Gut Microbiota Assemblages Shows Minimal Effects of Host Genetics on Microbial Structure and Inferred Function.

The microbiota of teleost fish has gained a great deal of research attention within the past decade, with experiments suggesting that both host-genetics and environment are strong ecological forces shaping the bacterial assemblages of fish microbiomes. Despite representing great commercial and scientific importance, the catfish within the family , specifically the blue and channel catfish, have received very little research attention directed toward their gut-associated microbiota using 16S rRNA gene sequencing. Within this study we utilize multiple genetically distinct strains of blue and channel catfish, verified via microsatellite genotyping, to further quantify the role of host-genetics in shaping the bacterial communities in the fish gut, while maintaining environmental and husbandry parameters constant.

Identification of Four Distinct Phylogenetic Groups in With Fish Host Associations.

Columnaris disease, caused by the Gram-negative bacterium , is one of the most prevalent fish diseases worldwide. An exceptionally high level of genetic diversity among isolates of has long been recognized, whereby six established genomovars have been described to date. However, little has been done to quantify or characterize this diversity further in a systematic fashion.

Comparative Phenotypic and Genotypic Analysis of Edwardsiella Isolates from Different Hosts and Geographic Origins, with Emphasis on Isolates Formerly Classified as E. tarda, and Evaluation of Diagnostic Methods.

spp. are responsible for significant losses in important wild and cultured fish species worldwide. Recent phylogenomic investigations have determined that bacteria historically classified as actually represent three genetically distinct yet phenotypically ambiguous taxa with various degrees of pathogenicity in different hosts.