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C. E. Starliper

Publications and source records attributed to C. E. Starliper.

At least 19 recordsLinked to original sources
USGS2011

Efficacy and toxicity of iodine disinfection of Atlantic salmon eggs

Recent interest in the restoration of Atlantic salmon Salmo salar in the Great Lakes has given rise to new culture techniques and management programs designed to reduce pathogen transmission while stabilizing and enhancing wild populations. We examined the toxicity of iodine to Atlantic salmon eggs and its effectiveness as a disinfectant against bacteria on egg surfaces. We spawned and fertilized eight gravid Atlantic salmon from Cayuga Lake, New York, and exposed their eggs to 10 concentrations of iodine (5, 10, 50, 75, 100, 500, 750, 1,000, 5,000, and 7,500 mg/L) for 30 min during water hardening. An additional subsample of unfertilized eggs was also exposed to some of the same concentrations of iodine (5, 10, 50, 75, and 100 mg/L) to determine the efficiency of disinfection. Viable eggs were only obtained from four females. Survival of eggs to the eyed stage and hatch tended to be reduced at iodine concentrations of 50 and 75 mg/L and was significantly reduced at concentrations of 100 mg/L iodine or more. We calculated the concentrations of iodine that killed 50% of the Atlantic salmon eggs at eye-up and hatch to be 175 and 85 mg/L, respectively. Aeromonas veronii, A. schubertii, A. hydrophila, A. caviae, Plesiomonas shiggeloides , and Citrobacter spp. were the predominant bacteria present on the surface of green eggs and were significantly reduced by an iodine immersion. The use of iodine as a disinfectant on Atlantic salmon eggs was effective at low concentrations (50–75 mg/L), for which toxicity to Atlantic salmon was minimal.

North American Journal of Aquaculture↗
USGS2011

Predominant bacteria isolated from moribund Fusconaia ebena ebonyshells experiencing die-offs in Pickwick Reservoir, Tennessee River, Alabama

Mussel die-offs have been noted in recent years in Pickwick Reservoir, Tennessee River, Alabama. The primary affected species was Fusconaia ebena, but also affected to lesser degrees were Ellipsaria lineolata, Quadrula pustulosa, and Quadrula quadrula. These events were characterized by large numbers of empty shells—fresh-dead and live individuals that were presumed to be diseased because of weak and slow valve closure responses to external stimuli. Anecdotal evidence suggested the possible involvement of an etiological agent, such as a bacterial pathogen. The die-offs have occurred in Pickwick Reservoir (river miles 236–256) in sequential years during the past approximately 10 y. These timeframes have coincided with reduced basin inflows and warmer water temperatures. The majority of the moribund and freshly dead F. ebena were females possibly predisposed to infection and disease from ongoing reproductive activity. Affected and healthy-cohort mussels were collected to characterize the bacterial flora prior to, during, and after a July 2006 die-off, and during a subsequent die-off in September 2008. The numbers of total bacteria from both the 2006 and 2008 die-offs were significantly greater from the diseased specimens. For example, from the September 2008 die-off, the mean count from diseased F. ebena soft tissues was 9.75 × 10 6 cfu/g, which was more than 100 times greater (P = 0.025) than the mean from healthy cohorts (6.74 × 10 4 cfu/g). The predominant bacteria from affected F. ebena from July 2006 were Hafnia alvei and Aeromonas sobria, whereas from September 2008 the predominant bacteria were Enterobacter spp., Aeromonas schubertii, Aeromonas veronii bv. veronii, and Aeromonas veronii bv. sobria.

Alabama↗
USGS2010

Recovery of Renibacterium salmoninarum from naturally infected salmonine stocks in Michigan using a modified culture protocol

Renibacterium salmoninarum, the causative agent of bacterial kidney disease (BKD), is a fastidious and slow-growing bacterium that is extremely difficult to grow in vitro. Herein, we describe a modified primary culture protocol that encompasses a modified bacteriological culture medium and a tissue processing procedure. In order to facilitate the release of R. salmoninarum from granulomatous tissues, kidneys of infected fish were homogenized in a high speed stomacher. The kidney disease medium (KDM2), routinely used for primary culture of R. salmoninarum was modified by the addition of antibiotics and metabolites. When a relatively large inoculum of diluted kidney homogenate was streak-plate inoculated onto the modified KDM2, colonial growth of R. salmoninarum was achieved within 5-7. days, compared to the standard of two weeks or more. The modified procedure was then used to determine the prevalence of R. salmoninarum among representative captive and feral salmonid stocks in Michigan. Prevalence and clinical manifestations varied among species, strains of fish, and locations; however, R. salmoninarum isolates were biochemically homogenous. The improved primary culture procedure described in this study enabled selective and quick isolation of R. salmoninarum. Also, the isolates retrieved in this study constitute a unique biological resource for future studies of R. salmoninarum in the Laurentian Great Lakes. ?? 2009 University of Cairo.

Journal of Advanced Research↗
USGS2009

Immunization of salmonids against the fish pathogen, Aeromonas salmonicida

An avirulent strain of Aeromonas salmonicida was shown to lack “A-layer” protein exterior to the outer cell membrane, but was still immunogenic in fish. After bacteria were inactivated with chloroform, whole cells, soluble antigen and combined whole cell plus soluble antigen vaccines were prepared. Those brook trout ( Salvelinus fontinalis ) that were vaccinated by a 60-second immersion in the combined whole cell plus soluble antigen vaccine were protected against experimental challenges. Further immersion vaccinations of Atlantic salmon ( Salmo salar ) in the combined vaccine indicated that protection conferred by immunization was highly significant, efficacious, and reproducible. In field situations, mortality in brown trout ( S. trutta ) immersion-vaccinated in this preparation was 2.1% whereas that in control fish was 28.9% after natural challenge.

Journal of the World Mariculture Society↗
USGS2008

Recovery of a fish pathogenic bacterium, Aeromonas salmonicida, from ebonyshell mussels Fusconaia ebena using nondestructive sample collection procedures

Refugia are increasingly being used to maintain and propagate imperiled freshwater mussels for future population augmentations. Success for this endeavor is dependent on good husbandry, including a holistic program of resource health management. A significant aspect to optimal health is the prevention or control of infectious diseases. Describing and monitoring pathogens and diseases in mussels involves examination of tissues or samples collected from an appropriate number of individuals that satisfies a certain confidence level for expected prevalences of infections. In the present study, ebonyshell mussels Fusconaia ebena were infected with a fish pathogenic bacterium, Aeromonas salmonicida, through their cohabitation with diseased brook trout Salvelinus fontinalis. At a 100% prevalence of infection, the F. ebena were removed from the cohabitation tank to clean tanks that were supplied with pathogen-free water, which initiated their depuration of A. salmonicida. Three samples (nondestructive fluid, mantle, hemolymph) collected using nondestructive procedures were compared with fluids and soft tissue homogenates collected after sacrificing the mussels for recovery of the bacterium during this period of depuration. Nondestructive sample collections, especially ND fluid, provide a comparable alternative to sacrificing mussels to determine pathogen status.

Journal of Shellfish Research↗
USGS2008

General and specialized media routinely employed for primary isolation of bacterial pathogens of fishes

There are a number of significant diseases among cultured and free-ranging freshwater fishes that have a bacterial etiology; these represent a variety of gram-negative and gram-positive genera. Confirmatory diagnosis of these diseases involves primary isolation of the causative bacterium on bacteriologic media. Frequently used "general" bacteriologic media simply provide the essential nutrients for growth. For most of the major pathogens, however, there are differential and/or selective media that facilitate primary recovery. Some specialized media are available as "ready-to-use" from suppliers, while others must be prepared. Differential media employ various types of indicator systems, such as pH indicators, that allow diagnosticians to observe assimilation of selected substrates. An advantage to the use of differential media for primary isolation is that they hasten bacterial characterization by yielding the appropriate positive or negative result for a particular substrate, often leading to a presumptive identification. Selective media also incorporate agent(s) that inhibit the growth of contaminants typically encountered with samples from aquatic environments. Media that incorporate differential and/or selective components are ideally based on characters that are unique to the targeted bacterium, and their use can reduce the time associated with diagnosis and facilitate early intervention in affected fish populations. In this review, the concepts of general and differential/selective bacteriologic media and their use and development for fish pathogens are discussed. The media routinely employed for primary isolation of the significant bacterial pathogens of fishes are presented. ?? Wildlife Disease Association 2008.

Journal of Wildlife Diseases↗
USGS2007

Mycobacterial infections in striped bass from Delaware Bay

Eighty striped bass Morone saxatilis were obtained from Delaware Bay using commercial gill nets set adjacent to Woodland Beach (n = 70) and Bowers Beach (n = 10) in December 2003. Fish were examined for gross lesions. Total lengths (TLs) and eviscerated weights were determined to calculate condition factors (K). Portions of spleens were aseptically harvested for bacterial culture, and portions of spleens, kidneys (anterior and posterior), livers, and gonads were obtained for histological examination. The size distribution of the striped bass was relatively homogeneous; the mean TL was about 600 mm for all samples. Mean K exceeded 0.95 in all samples and was not significantly different (P > 0.05) among samples. Significant differences in mycobacterial infection prevalence (P ??? 0.05) were observed among samples; samples obtained at Woodland Beach (WB) on December 10 (53.8%, n = 13) and December 17 (7.1%, n = 42) exhibited the most striking differences in prevalence. Mycobacterial infection intensity ranged from 1 ?? 102 to 1 ?? 107 colony-forming units per gram of spleen. Acanthocephalan infection prevalence and intensity, non-acid-fast bacterial infection prevalence, and fish sex ratio were also significantly different among the samples (P ??? 0.05). Similar to the mycobacterial infections, differences in sex ratio, acanthocephalan infection, and non-acid-fast bacterial infection were observed between the WB samples taken on December 10 and 17. However, no significant associations (P > 0.05) were observed between sex ratio or these infections and mycobacterial infection. The differences in bacterial and parasite infection prevalence and intensity and fish sex ratio in some samples indicate that these fish had a different history and that the epizootiology of mycobacterial infection in striped bass from Delaware Bay may be relatively complex. ?? Copyright by the American Fisheries Society 2007.

Journal of Aquatic Animal Health↗
USGS2007

Improved husbandry to control an outbreak of rainbow trout fry syndrome caused by infection with Flavobacterium psychrophilum

Case Description - A cohort of 35,200, 13-week-old, female rainbow trout at a fish farm was evaluated because of a 2-week history of anorexia and lethargy and a mortality rate of approximately 100 fish/d. Clinical Findings - Affected fish were lethargic and thin and had disequilibrium, bilateral exophthalmia, pale red gills and kidneys, red-tinged coelomic fluid, and pale brown livers. Some fish were differentially pigmented bilaterally. The presumptive diagnosis was bacterial or viral septicemia. The definitive diagnosis was rainbow trout fry syndrome caused by infection with Flavobacterium psychrophilum. Treatment and Outcome - A strategy for controlling the outbreak based on reducing pathogen numbers in affected tanks and reducing pathogen spread among tanks was developed. The option of treating with antimicrobial-medicated feed was discussed with the farmer, but was declined. After changes were made, mortality rate declined quickly, with no more deaths within 10 days after the initial farm visit. Clinical Relevance - Bacterial coldwater disease is the most common manifestation of infection with F psychrophilum in fingerling and adult rainbow trout. However, the organism can also cause rainbow trout fry syndrome. This condition should be included on a list of differential diagnoses for septicemia in hatchery-reared rainbow trout fry.

Journal of the American Veterinary Medical Associa↗
USGS2005

Comparison of cortical bone and serum concentrations of clindamycin achievable by direct local infusion and intravenous administration

Tibial cortical bone and serum concentrations of clindamycin were compared using two drug delivery methods in dogs. An implantable drug pump, used to continuously infuse clindamycin directly into the cortical bone, was compared with clindamycin administered i.v. Dosage for the direct continuous infusion was 4 mg/kg/day, and 44 mg/kg/day for the i.v. bolus regimen. Serum concentrations of clindamycin were significantly higher during i.v. bolus administration when compared with those achieved during pump infusion (p < 0.05). However, tibial cortical bone concentrations were significantly higher during pump infusion than were those achieved by i.v. bolus. When examining serum and bone clindamycin concentrations over 21 days of direct local infusion, there was no significant difference in concentrations between sampling days within each tissue (p > 0.05). Furthermore, there were significantly greater concentrations of clindamycin in the cortical bone than in the serum at each sampling period (p < 0.05). Results indicate that delivery of clindamycin to canine bone by implantable drug pump achieve significantly higher bone concentrations than i.v. bolus administration of the drug at higher dosages. Direct infusion also can sustain high concentrations in cortical bone without increasing systemic concentrations of clindamycin.

Journal of Orthopaedic Research↗
USGS2001

The effect of depuration on transmission of Aeromonas salmonicida between the freshwater bivalve Amblema plicata Arctic char

A model system was used to study bacterial fish pathogen transmission between the freshwater bivalve Amblema plicata and two strains (Nauyuk and Labrador) of Arctic char Salvelinus alpinus. Aeromonas salmonicida , the cause of fish furunculosis, was readily transmitted from Arctic char to A. plicata and vice versa via simple cohabitation. Clinical furunculosis was artificially established in Nauyuk Arctic char via horizontal exposure to Labrador Arctic char that received intraperitoneal injections of A. salmonicida. After the Nauyuk Arctic char began to die, A. plicata were placed in the tank with the fish. After 33 d of cohabitation, a group of 10 A. plicata was cultured, and A. salmonicida was isolated from all 10. The remaining A. plicata were transferred to other tanks being supplied with specific-pathogen-free water. At 1, 5, 15, and 30 d after transfer, 60 uninfected Labrador Arctic char were cohabitated with the A. plicata. Transmission of A. salmonicida from A. plicata to the Arctic char was evaluated via fish mortality and bacterial culture after 3–4 weeks of exposure. Mortality to A. salmonicida occurred in groups exposed to A. plicata after 1 and 5 d of depuration but not in groups exposed after 15 and 30 d. The bacterium was not isolated from either the A. plicata or the Arctic char in the 15- and 30-d groups. Results indicate that the current minimum 30-d quarantine of freshwater bivalves destined for relocation to prevent spread of zebra mussels Dreissena polymorpha is sufficient to allow depuration of a fish pathogen and, thus, to prevent the spread of disease.

West Virginia↗
USGS2001

Kenneth Wolf honored

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People, Land, and Water↗
USGS1998

Biochemical and conjugation studies of romet-resistant strains of Aeromonas salmonicida from salmonid rearing facilities in the eastern United States

Strains of Aeromonas salmonicida ( n = 585) were collected from covertly infected and diseased salmonid hosts from 12 hatcheries in the eastern United States. Strains and sites were selected because of their potential for harboring antimicrobial resistance, in particular, to Romet™. Resistance to Romet was displayed by 315 strains (53.8%), which were isolated from all six host species sampled at 10 of 12 sites. Thirty of the resistant strains (9.5%) from five sites had no zone of inhibition, whereas the other strains had either confluent growth or resistant colonies within a zone of inhibition. Fifty-one resistant strains, representing each of the three resistance phenotypes, were selected for biochemical and antimicrobial comparisons with Romet-sensitive strains. All were confirmed to be A. salmonicida , and no characteristic biochemical phenotypes were found to be associated with resistance to Romet. Differential resistances between resistant and sensitive strains were detected to the antimicrobials oxytetracycline, tetracycline, sulfadiazine, sulfamethizole, trimethoprim, and SXT, a potentiated sulfonamide composed of trimethoprim and sulfamethoxazole. Plasmid DNA isolation and agarose gel electrophoresis were done for 25 Romet-resistant strains, and R-plasmids, not present in sensitive strains, were detected in 23 of these. Two different sizes of R-plasmids were detected, one about 55 kilobase pairs long and another about 50 kilobase pairs. Two strains isolated from New York brook trout Salvelinus fontinalis had reduced confluent growth within a zone of inhibition but contained no large plasmids. This may indicate chromosomally mediated resistance. Conjugational mating studies evaluated transfer of the R-plasmid DNA using eight Escherichia coli recipients. Successful R-plasmid transfer was accomplished with two donor strains (MI1 and MI2 from New Hampshire brook trout). Our results, in addition to those of other workers, illustrate the widespread resistance in A. salmonicida to approved antimicrobials and the capacity of this bacterium to become resistant in the fish culture environment.

Journal of Aquatic Animal Health↗