Vaccine efficacy in preventing clinical disease has been well characterized. However, vaccine impacts on transmission under diverse field conditions, such as variable pathogen exposure dosages, are not fully understood. We evaluated the impacts of vaccination on disease-induced host mortality and shedding of infectious hematopoietic necrosis virus (IHNV) in rainbow trout Oncorhynchus mykiss. Fish,

Withering syndrome (WS) is a chronic bacterial disease that affects numerous northeastern Pacific abalone Haliotis spp. The causative agent of WS is an obligate intracellular Rickettsiales-like bacterium (WS-RLO) that remains unculturable, thereby limiting our understanding of WS disease dynamics. The objectives of our study were to (1) determine the temporal stability of WS-RLO DNA outside of its

The production of tilapia Oreochromis spp. is rapidly growing throughout the world, but atypical motile aeromonad septicemia (MAS) is a current threat to the tilapia farming industry. The etiological agent of this disease is usually Aeromonas hydrophila. Mortality rates due to MAS are frequently high, resulting in a devastating negative impact on this industry worldwide; therefore, proper control measures

The Rainbow Trout Oncorhynchus mykiss is a salmonid fish that is maintained in aquaculture facilities and used as a source of protein around the world. Veterinarians need accurate, efficient tools and straightforward assessments to evaluate the health status of fish, like Rainbow Trout, that are cultivated on farms. In this study, two genetically distinct broodstock lines of Rainbow Trout originally

During recent decades, survey studies have documented the widespread presence of oocytes in the testes of male Smallmouth Bass Micropterus dolomieu collected from surface waters throughout the United States. There are few published reports of testicular oocytes (TO) in Smallmouth Bass before the 1990s, so it is difficult to know how long this has been occurring. Consequently, this study was conducted

Cyprinid herpesvirus 3, also known as koi herpesvirus (KHV), is an important pathogen in common and koi carp Cyprinus carpio, varieties. Two main genotypes of KHV have been reported worldwide that are associated with Asian and European origins. In the USA, outbreaks of KHV diseases have been reported in different states since the early 1990s; however, the diversity of KHV is unknown. In the current

Serum protein electrophoresis (EPH) is used to assess relative concentrations of blood proteins in clinical and biological studies. Serum EPH fractions have been determined for elasmobranchs using mammalian albumin, alpha 1-, alpha 2-, beta-, and gamma-globulin fractions, and have been deemed Fractions 1 through 5 respectively. However, serum EPH fraction concentration reference intervals (RI) have

Erysipelothrix piscisicarius is an emergent pathogen in fish aquaculture, particularly in the ornamental fish trade. Very little is known on the biology of this pathogen; however, the recurrence of infection and disease outbreaks after removing the fish from a system and disinfecting the tank suggest its environmental persistence. Moreover, biofilm lifestyle in E. piscisicarius has been suspected but

The genetic diversity of Vibrio anguillarum pJM1-like plasmids was investigated. Plasmids were isolated from 18 V. anguillarum serovar O1 strains collected from different geographic locations and fish species. The plasmids were sequenced and compared with the complete sequence of the published virulence plasmid pJM1. All 18 strains contained pJM1-like plasmids with approximately 65 kbp and all plasmids

Viral hemorrhagic septicemia virus (VHSV) is an ongoing cause of disease and mortality in freshwater fishes across the Great Lakes region of the Midwestern United States. Antibody detection assays such as enzyme-linked immunosorbent assay (ELISA) are nonlethal serological methods that can have significantly shorter turnaround times than the current validated viral detection diagnostic methodology for

A viromics study on the intestinal contents of migratory wild ducks of the genera Anas, Mareca, Spatula, and Oxyura during their winter stay in Mexico showed the presence of the virus family Alloherpesviridae. The genus Cyprinivirus is part of this family and includes cyprinid herpesvirus 3 (CyHV3). This is the etiological agent of the lethal disease known as koi herpesvirosis, which affects different

Parasites can compromise the health and fitness of individual fish, and it is important to generate baseline information that can then be used to document changes in the abundance and distribution of potentially pathogenic parasites. The ectoparasitic copepod Salmincola edwardsii was assessed with respect to prevalence (percentage of infected fish per site), infection intensity (number of parasites

Carbendazim (CBZ) is a widely used, systemic, broad-spectrum benzimidazole fungicide. It is used worldwide against fungal diseases on a wide range of agricultural products and in domestic gardens. The activities of brain oxidative stress biomarkers and acetylcholinesterase (AChE) in juvenile African Catfish Clarias gariepinus exposed to CBZ were investigated. Juveniles were exposed to sublethal concentrations

The order Saprolegniales (Class Oomycota) is a group of fungus-like eukaryotic microorganisms that have been associated with infections in fish and fish eggs. Infections with microorganisms from this order are clearly evident because they have a cotton wool-like appearance. The aim of this study was to characterize and identify an oomycete that was isolated from the eye of an Orange Blotched Peacock

The aim of the present study was to characterize two gram-negative bacterial strains that were isolated from diseased Atlantic Horse Mackerel Trachurus trachurus in 2017. Based on the results obtained from the biochemical and chemotaxonomic characterization, the isolates were identified as Lacinutrix spp. The highest similarity of the 16S rRNA gene sequences was obtained with the strain L. venerupis

In this study, levels of Vibrionaceae, Staphylococcaceae, and Enterobacteriaceae were observed in seawater from juvenile green turtle Chelonia mydas rearing tanks and in the incoming coastal seawater (the water supply). Bacterial loads were compared between the incoming coastal seawater and two different rearing conditions: in cement tanks at a low stocking density and in fiberglass tanks at a high

An outbreak of suspected iridovirus disease in cultured hybrid grouper (♀Tiger Grouper Epinephelus fuscoguttatus × ♂ Giant Grouper Epinephelus lanceolatus) occurred in the Guangxi Province in July, 2018. In this study, grouper iridovirus Guangxi (SGIV-Gx) was isolated from diseased hybrid grouper that were collected from Guangxi. Cytopathic effects were observed and identified in grouper spleen cells

Macrophage aggregates (MAs) are focal accumulations of pigmented macrophages in the spleen and other tissues of fish. A central role of MAs is the clearance and destruction of degenerating cells and recycling of some cellular components. Macrophage aggregates also respond to chemical contaminants and infectious agents and may play a role in the adaptive immune response. Tissue damage or physiological

The ingestion of infected prey is the most recognizable mode of transmission for Ichthyophonus, but because this mode of transmission is unidirectional from small prey fish to larger predators, it cannot sustain the parasite within or among populations nor does it explain transmission to planktivores. Recently, waterborne transmission was demonstrated in cultured Rainbow Trout Oncorhynchus mykiss,

Acute hepatopancreatic necrosis disease (AHPND) is a new emerging bacterial disease that has been recently reported to cause mass mortalities in Pacific whiteleg shrimp Penaeus vannamei. Antibiotics have been used to treat bacterial diseases in shrimp, but most of them have been ineffective and have resulted in drug residues in the harvested shrimp products. In this study, an alternative approach was

Molecular tools, such as high-throughput quantitative polymerase chain reaction (HT-qPCR), are useful for monitoring multiple infectious agents in wild animal populations (i.e., broad-based screening). If destructive tissue samples cannot be obtained due to experimental design requirements (e.g., bio-telemetry; holding with repeated biopsy) or the conservation status of host species, then nonlethally

This study evaluated the potential of three essential oils (EOs) that were obtained from coriander Coriandrum sativum (CEO), linaloe tree Bursera delpechiana (BEO), and lavender Lavandula hybrida (LEO) as anesthetic agents. Convict Cichlids Amatitlania nigrofasciata (Günther 1867) were exposed to eight concentrations of anesthetic (50, 75, 100, 125, 150, 200, 250, and 300 μL/L). After exposure to the

This study describes antibiotic use by small-scale freshwater aquaculture farmers in the upper Mekong Delta in southwestern Vietnam and the knowledge and practices surrounding the cause and prevention of aquaculture disease in that region. Forty five farmers were included in the study, of which 19 (42%) cultivated tilapia Oreochromis spp., 13 (29%) Striped Catfish Pangasianodon hypophthalmus and 13

Commercially available culture media and supplements were tested for their potential to produce primary cell cultures from tissues of Indian mud crabs Scylla serrata. Eight commercially available culture media from Sigma-Aldrich (Leibovitz's L-15, Medium 199, Grace's Insect Medium, Minimal Essential Medium, Dulbecco's Modified Eagle Medium, TC-100 Insect Medium, IPL-41 Insect Medium, and Roswell Park

Flavobacterium psychrophilum produces biofilms under laboratory conditions, and it has been inconclusively suggested that F. psychrophilum biofilms can be a potential reservoir for transmission of the pathogen to a fish population under fish farming conditions. Therefore, there is a need for anti-biofilm compounds. The main aim of this study was to determine the anti-biofilm properties of certain compounds

An analysis of daily water samples collected from an index site on Big Soos Creek, Washington indicated intra-annual differences in the concentrations of waterborne Nanophyetus salmincola. Waterborne concentrations, quantified as gene copies/L, peaked during the fall (October-November 2016), decreased to very low concentrations over the winter (January-March 2017), and then increased in the spring

Coelomic fluid sampling is a noninvasive technique that is used to access the body fluid of sea stars for diagnostics and research. Given recent mortality events including sea star wasting disease, which has killed millions of sea stars along the Pacific coast since 2013, there is a need for validated diagnostic tests to evaluate sea star health. The objectives of this study were to establish coelomic

Henneguya ictaluri is the etiologic agent of proliferative gill disease (PGD) in farm-raised Channel Catfish Ictalurus punctatus and hybrid catfish in the southeastern United States, and significant annual losses are attributed to this disease. Research suggests that H. ictaluri infection dynamics in Blue Catfish I. furcatus and hybrid catfish (Channel Catfish × Blue Catfish) differ from those in Channel

Fibropapillomatosis of sea turtles is traditionally treated with surgical debulking techniques that are often associated with prolonged healing and tumor recurrence. Electrochemotherapy was recently described for green turtles Chelonia mydas and can be an alternative to surgery and even general anesthesia. The objectives of this study were to replicate an electrochemotherapy protocol from a previous

Topical treatment for wound management in fish is challenging due to their aquatic life. The objective of the present study was to assess the effect of a topical gel containing misoprostol and phenytoin on the healing of skin wounds in Brook Trout Salvelinus fontinalis. Four 16- × 8-mm, full-thickness wounds were created in each trout. Fish were randomly assigned either to the misoprostol/phenytoin

The objectives of this study were to describe a minimally invasive coelomic fluid sampling technique in elasmobranchs, to characterize the coelomic fluid composition in clinically normal and abnormal animals, and to compare findings from wild and managed populations. Fluid was collected via the coelomic pore in 89 individuals from 16 species spanning clinically normal and abnormal patients within a

Viral hemorrhagic septicemia virus (VHSV) is an important viral pathogen in the culture of Olive Flounder Paralichthys olivaceus. Based on cumulative mortality, the virulence of VHSV was found to be highly different depending on challenge routes and exposure doses (using tissue culture infectious dose with 50% endpoint [TCID50]). Olive Flounder were injected with VHSV at 102.5 , 104.5 , 106.5 , and

This study investigated the environmental factors associated with the presence of Vibrionaceae in economically important cage-cultured tropical marine fishes: the Asian Seabass Lates calcarifer, snapper Lutjanus sp., and hybrid grouper Epinephelus sp. Fish sampling was conducted at monthly intervals between December 2016 and August 2017. The body weight and length of individual fish were measured,

Juvenile Sablefish Anoplopoma fimbria were used to assess the effects of water temperature (8, 10, 12, 14, 16, 18, and 20°C) on hematological parameters and heat shock proteins 70 and 90 for 4 months. Hematological parameters, including red blood cell count, hematocrit, and hemoglobin, were significantly decreased at 18°C. The inorganic plasma components calcium and magnesium were not altered by water

The oxidative status and intestinal and liver histology of Barramundi Perch Lates calcarifer juveniles were investigated in an experiment using different tank colors (black, red, blue, and white) over 6 weeks. It has been previously shown that background color can affect physiological processes in different species. The background colors did not cause significant differences in malondialdehyde, catalase

The rat lungworm Angiostrongylus cantonensis is a nematode parasite that can cause potentially fatal eosinophilic meningitis in humans. The life cycle of A. cantonensis involves multiple hosts, with the most common terminal hosts being rodents and intermediate hosts comprising gastropods. One such gastropod is the invasive island apple snail Pomacea maculata, which is native to South America but is

The genus Aeromonas comprises more than 60 recognized species that include many important fish pathogens such as the causative agents of furunculosis and motile Aeromonas septicemia (MAS). Although MAS is typically considered a secondary infection, a new virulent A. hydrophila (vAh) strain has been causing devastating losses to the catfish industry in Alabama since 2009. The objective of this study

Herbal supplements are suitable for improving fish health and combating diseases in fish culture. However, the mechanism of action of many herbal mixtures remains unclear. This study was conducted to evaluate the effects of traditional Chinese medicine (TCM; a mix of Astragalus membranaceus, Angelica sinensis, and Crataegus hupehensis at a ratio of 1:1:1 on a weight basis) on growth, immune response

Fish kill investigations are critical to understanding threats to aquatic ecosystems and can serve as a measure of environmental disruption as well as an early indicator of emerging disease. The goal of this study was to analyze historical data related to such events among wild fish populations in Minnesota in order to assess the quality and completeness of the data and potential trends in fish kills

The Comal River, a spring-fed system in central Texas, was invaded in the 1960s by two Asian aquatic snails (Thiaridae: red-rimmed melania Melanoides tuberculata and quilted melania Tarebia granifera) and subsequently by three of their trematode parasites (the avian eye-fluke Philophthalmus gralli in the 1960s; the gill trematode Centrocestus formosanus in the 1990s; and the intestinal fluke Haplorchis

The present study supports the usefulness of ancillary techniques, such as immunohistochemistry, as a valid diagnostic tool in the field of fish oncology. The immunohistochemical patterns observed in four neoplasms on four individual teleosts belonging to different species are described. Cytokeratin, vimentin, actin, S100, calretinin, and Melan-A antibodies were used. Diagnoses of papilloma in a Bream

Glycogen is a primary metabolic reserve in bivalves and can be suitable for the evaluation of bivalve condition and health status, but the use of glycogen as a diagnostic tool in aquaculture and biomonitoring is still relatively rare. A tissue biopsy combined with a simplified phenol-sulfuric acid method was used in this study to evaluate the inter- and intraindividual variation in the glycogen concentrations

In September 2016, a marine fish farm operator in Selangor, Malaysia, reported a disease outbreak affecting juvenile hybrid groupers (Camouflage Grouper Epinephelus polyphekadion × Tiger Grouper E. fuscoguttatus). The average daily mortality was 120 fish, resulting in a cumulative mortality rate of 29% within 10 d. The affected hybrid groupers displayed lethargy, excessive mucus production, rotten

Over the past century, populations of Lake Trout Salvelinus namaycush have declined throughout the Great Lakes basin due to overfishing, habitat destruction, introduction of invasive species, and associated recruitment issues from high thiaminase, as well as emerging infectious diseases. To combat these declines, state and federal fishery management agencies undertook substantial stock enhancement

The present study was conducted to explore the occurrence of Flavobacteriaceae in wild Nile Tilapia Oreochromis niloticus (n = 108) collected from Lake Victoria and farmed Nile Tilapia (n = 187) collected from 12 ponds in the Morogoro region of Tanzania. The size of the ponds surveyed ranged from 130 to 150 m2 . Pond parameters and fish morphometric data were recorded during sampling. In total, 67

The ability of formalin, PEROX-AID (hydrogen peroxide), and seawater to kill waterborne Nanophyetus salmincola cercariae was evaluated in vitro. Newly emerged cercariae survived for extended periods in freshwater, with 53-73% survival occurring in negative control groups after 24 h. Exposure to dilutions of formalin reduced this survival time, with 0% of cercariae surviving after 30 min in 450 μL/L

The salmon louse Lepeophtheirus salmonis, a type of sea lice (family Caligidae), is enzootic in marine waters of British Columbia and poses a health risk to both farmed Atlantic Salmon Salmo salar and wild Pacific salmon Oncorhynchus spp. At the adult stage, sea lice infections can often result in severe cutaneous lesions in their salmonid hosts. To evaluate and compare the physiological consequences

During a routine health inspection of apparently healthy wild-caught common mudpuppies Necturus maculosus, the bacteria Yersinia ruckeri was isolated and the identity confirmed using biochemical and molecular methods. This represents the first isolation of Y. ruckeri from an amphibian. This finding increases the known host range capable of harboring this important fish pathogen and could have serious

Current growth in aquaculture production is parallel with the increasing number of disease outbreaks, which negatively affect the production, profitability, and sustainability of the global aquaculture industry. Vibriosis is among the most common diseases leading to massive mortality of cultured shrimp, fish, and shellfish in Asia. High incidence of vibriosis can occur in hatchery and grow-out facilities

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a rapid, cost-effective method for identification of a broad range of bacterial taxa, but its accuracy for Vibrio spp. from samples of aquatic animal origin is unknown. We used DNA sequence analysis targeting two conserved genes, rpoB and rpoD, as the identification standard for 5 reference strains and 35

Coelomic fluid aspiration has been utilized in echinoderms in research and clinical settings. Detailed procedural descriptions for coelomic fluid sampling in sea urchins (class Echinoidea) are lacking, and samples are prone to contamination. The objectives of this study were to (1) standardize a technique for coelomic fluid collection in long-spined sea urchin Diadema antillarum that optimizes the

Indigenous small cyprinid fish species play an important role in Great Lakes ecosystems and also comprise the backbone of a multimillion-dollar baitfish industry. Due to their widespread use in sport fisheries of the Laurentian Great Lakes, there are increasing concerns that baitfish may introduce or disseminate fish pathogens. In this study, we evaluated whether baitfish purchased from 78 randomly

Global amphibian decline continues to be a great concern despite our increased understanding of the causes behind the observed patterns of the decline, such as habitat modification and infectious diseases. Although there is a large body of literature on the topic of amphibian infectious diseases, pathogen prevalence and distribution among entire communities of species in many regions remain poorly

The newly emerging tissue microbiota hypothesis suggests that bacteria found in blood and tissues play a role in host health, as these bacterial communities have been associated with various noncommunicable diseases such as obesity, liver disease, and cardiovascular disease. Numerous reports have identified bacteria in the blood of healthy finfish, indicating bacteremia may not always indicate disease

Advances in technology are making it easier for rapid field detection of microbes in aquaculture. Specifically, real-time quantitative PCR (qPCR) analysis, which has traditionally been confined to laboratory-based protocols, is now available in a handheld, field-portable system. The feasibility of using the Biomeme handheld qPCR system for rapid (<50 min) on-site detection and monitoring of Flavobacterium

Introduced pathogens can affect fish populations, and three main factors affect disease occurrence: the environment, host, and pathogen. Manipulating at least one of these factors is necessary for controlling disease. Myxobolus cerebralis, the parasite responsible for salmonid whirling disease, became established in Colorado during the 1990s and caused significant declines in wild Rainbow Trout Oncorhynchus

Placer Creek, a tributary of Sangre de Cristo Creek in Colorado's San Luis Valley, supported an allopatric core conservation population of native Rio Grande Cutthroat Trout Oncorhynchus clarkii virginalis during much of the 20th century. After the failure of gabion barriers in the late 1990s, Brook Trout Salvelinus fontinalis infected with Myxobolus cerebralis invaded from Sangre de Cristo Creek. By

No vaccine is yet commercially available against Mycobacterium marinum, the etiological agent of fish mycobacteriosis (also known as "fish tuberculosis"). The mycobacterial gene responsible for invasion and intracellular persistence, iipA, is known to moderate M. marinum pathology in Zebrafish Danio rerio. Two doses of heat-killed, wild-type, virulent M. marinum and two doses of a heat-killed, avirulent

Traditional methodologies to identify fish pathogens require euthanasia before the collection of tissue samples. While these methods are standardized and proven, there are instances where nonlethal alternatives would be preferred. Despite the need to develop nonlethal sampling techniques, few publications have focused on them and even fewer have used these approaches to identify viruses from infections