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Edwardsiella piscicida is an emergent global fish pathogen with a wide host range, although host associations driving genetic diversity remain unclear. This study investigated the genetic and virulence diversity of 37 E. piscicida isolates recovered from 10 fish species in North America. Multilocus sequence analysis (MLSA) was conducted using concatenated alignments of the gyrB, pgi and phoU sequences. MLSA clustered the tested isolates into six discrete clades. In light of recent disease outbreaks in cultured salmonids, the virulence of each clade was evaluated in Chinook salmon Oncorhynchus tshawytscha fingerlings following intracoelomic challenge of ~106 CFU/fish. Challenged and control fish were monitored for 21d, and microbiological and histological examination was performed on dead and surviving fish. Peak mortality occurred 3-5 days post-challenge (dpc) regardless of isolate or genetic group. Edwardsiella piscicida was recovered from all moribund and dead animals. At 21 dpc, fish challenged with isolates from clades II, III and IV presented cumulative mortality ≥83.3%, whereas isolates from clade I, V and VI resulted in cumulative mortality ≤71.4%. This study suggests an underlying genetic basis for strain virulence and potential host associations. Further investigations using other fish models and variable challenge conditions are warranted.

The genus Edwardsiella is composed of a diverse group of facultative anaerobic, gram-negative bacteria that can produce disease in a wide variety of hosts, including birds, reptiles, mammals, and fish. Our report describes the isolation and identification of Edwardsiella piscicida associated with chronic mortality events in 2 separate captive largemouth bass ( Micropterus salmoides) populations in New York and Florida. Wet-mount biopsies of skin mucus, gill, kidney, and spleen from several affected largemouth bass contained significant numbers of motile bacteria. Histologic examination revealed multifocal areas of necrosis scattered throughout the heart, liver, anterior kidney, posterior kidney, and spleen. Many of the necrotic foci were encapsulated or replaced by discrete granulomas and associated with colonies of gram-negative bacteria. Initial phenotypic and matrix-assisted laser desorption ionization–time of flight mass spectrometric analysis against existing spectral databases of recovered isolates identified these bacteria as Edwardsiella tarda. Subsequent molecular analysis using repetitive sequence mediated and species-specific PCR, as well as 16S rRNA, rpoB, and gyrB sequences, classified these isolates as E. piscicida. As a newly designated taxon, E. piscicida should be considered as a differential for multiorgan necrosis and granulomas in largemouth bass.

Two specimens of the Caribbean spiny lobster Panulirus argus captured by lobster fishers offshore of southeast Florida, USA, between late 2007 and early 2008 had completely white abdominal muscle tissue with a 'cooked' appearance. Wet-mount examination of the skeletal muscle tissue revealed masses of microsporidian spores. Histopathology of longitudinally sectioned skeletal muscle showed that the microsporidian spores displaced much of the muscle mass, but were interspersed with small empty vacuoles (approximately 5 microm in diameter) found adjacent to necrotic skeletal muscle. Skeletal muscle showed both liquefactive and coagulative necrosis. Transmission electron microscopy of the microsporidian spores revealed characteristics--including microvilli extending from the surface of the exospore, a unikaryotic spore (width 1.0 +/- 0.13 microm, range 0.8 to 1.4 microm; length 1.4 +/- 0.11 microm, range 1.2 to 1.6 microm; mean +/- SD, N = 16), and an isofilar polar filament-consistent with the genus Ameson, which is known to infect other palinurid lobsters. Microsporidiosis in Caribbean spiny lobsters has rarely been reported within the lobster's range, with only one brief report coming from the Florida Keys in 1976. Potential risks to the lobster fishery are unknown but warrant further study.

This article guides the technician through the basic principles of fish health. Nutrition, including the proper storage of fish foods, is discussed,as are the varying dietary needs of fish. The ability to recognize water-quality problems is emphasized, especially the conditions that commonly result in high mortality. Collection of specimens for microscopic examination or other diagnostic tests is explained.

A public aquarium with a 4-mo history of occasional fish mortalities submitted for necropsy an adult female largemouth bass (Micropterus salmoides) that died unexpectedly. Gross necropsy revealed that the pericardial cavity was markedly distended with partially coagulated blood. Examination of the heart revealed multiple nodular masses in the area of the atrium and two small perforations on the surface of one of the nodular masses. Histopathologic exam of the atrium revealed severe fibrinonecrotic endocarditis and transmural myocarditis with intralesional bacteria. A pure culture of Edwardsiella tarda was obtained from culture of posterior kidney and spleen. An area of stagnant water that may serve as the source of E. tarda was identified, and steps to rectify this problem were taken. Low-level supersaturation was also a significant stressor; the source of the supersaturation was not identified. To our knowledge, this is the first report of cardiac tamponade in a largemouth bass.

Introduction Couples choose marriage for themselves hoping to build a future with one special person. According to the National Marriage Resource Center (2009, para. 5), "eighty two percent of young adults aged 18-30 plan to get married and stay married for life. However, approximately 40% of first marriages end in divorce." Marriage education programs, also known as marriage enrichment programs, have emerged as opportunities to assist couples in the development of a healthy marriage relationship. A review of marriage education showed marital education programs consistently lead to an improvement of communication skills and relationship satisfaction (Halford, Markman, Kline, & Stanley, 2003). A meta-analytic review of 117 studies found Marriage and Relationship Education (MRE) to produce significant, moderate effect sizes on the outcomes of relationship quality and communication skills (Hawkins, Blanchard, Baldwin, & Fawcett, 2008), and a meta-analysis review of outcome research of premarital prevention programs revealed these programs to be effective in gains in interpersonal skills and overall relationship quality (Carroll & Doherty, 2003). Although comprehensive literature reviews indicate marriage enrichment programs are effective in improving relationship skills and marital satisfaction (Silliman, Stanley, Coffin, Markman, & Jordan, 2001), there is a lack of information about the effectiveness of specific programs (Bowling, Hill, & Jencius, 2005; Jakubowski, Milne, Brunner, & Miller, 2004) and the process of change facilitating the improved marriage relationship (Wilson & Halford, 2008). While quantitative research has been the primary methodology used for the majority of studies conducted on marriage, qualitative research can complement that work by helping to understand the marriage education experience of individuals and couples in the process of change and how the marriage education experience specifically assists couples in improving marital relationships. Results from a previous study of Married and Loving It![R] participants, a research-based marriage education program which has been in use since 2000, indicate overall marital satisfaction increased after participating in the program (Petty, 2003). The present qualitative study was designed to gain further understanding of the positive changes in the marriage through participating in Married and Loving It![R] and what specific components of the learning experience facilitated the change. Program Overview As an Extension Educator with the University of Idaho, I provide family life education to county residents in response to identified needs. After receiving a request for marriage education and not finding a program to fit our educational setting, my husband and I developed Married and Loving It![R] Over 400 people in Idaho have participated in the program and the curriculum has been distributed to over 45 states and seven foreign countries. Evaluations completed during the last class of the program have resulted in simple statements addressing the participant's satisfaction with the program, knowledge gain and initial changes in behavior. However there is a lack of in-depth scholarly research to gain additional knowledge as to the impact of the marriage education experience on the marriage relationship and the teaching components of the learning experience facilitating the change of an improved marriage. Adult educators are most effective when they know what specific aspects of the educational experience have the greatest impact for the participants. Married and Loving It![R] is a marriage education program designed to strengthen marriage relationships by presenting research-based information about successful and happy couples and by teaching relationship enhancement skills through a series of five classes. Classes are offered one night a week for two hours for five consecutive weeks or over a weekend. …

Megalocytiviruses cause systemic disease in both marine and freshwater fishes, negatively impacting ornamental and food fish aquaculture. In this report, we characterize a megalocytivirus infection in a captive marine ornamental fish, the orbiculate batfish Platax orbicularis. Histologic examination revealed cytomegalic cells characterized by strongly basophilic granular intracytoplasmic inclusions within various organs. Transmission electron microscopy revealed icosahedral virus particles within the cytoplasm of cytomegalic cells consistent with an iridovirus infection. Analysis of the major capsid protein gene sequence confirmed that the orbiculate batfish virus is a member of the family Iridoviridae and is identical to the only other megalocytivirus reported from a marine ornamental fish, the Banggai cardinalfish Pterapogon kauderni iridovirus.

Five wild-caught Lined Seahorses Hippocampus erectus from an aquarium system presented with altered buoyancy and distended upper trunks. Radiography of one specimen revealed a reduced air volume in the gas bladder. Pneumocystocentesis revealed a brown exudate of numerous leukocytes, parasite ova, and Gram- and acid-fast-positive bacilli under wet mounts and stains. Necropsies revealed enlarged, friable kidneys and distended gas bladders containing copious purulent exudate, necrotic tissue, and adult digeneans Dictysarca virens. Bacterial isolates from exudate cultures grown on Lowenstein-Jensen medium were identified as Gordonia sp. and Mycobacterium poriferae by high-performance liquid chromatography and 16S ribosomal DNA sequencing. Histopathology demonstrated a histiocytic response in kidney and gas bladder exudate, inflammation of the gas bladder wall, and infection of the gas bladder lumen with parasite ova and acid-fast-positive and Gomori's methenamine silver-positive bacilli. Praziquantel is prescribed for digenean infections but dissolves incompletely in seawater and is toxic to this host. Eradication of intermediate host vectors is a management option. Treatment of Gordonia infection has not been addressed in nonhuman animals, and there is no known effective treatment for Mycobacterium spp. infection in fishes. This is the first case report of digenean infection of the gas bladder in a syngnathid, Gordonia sp. infection in a nonhuman animal, and M. poriferae infection in a fish.

Extracellular ionized calcium (Ca(2+)) is the primary physiological regulator of parathyroid hormone (PTH) secretion and the G protein-coupled receptor (CaR) that mediates this response has been cloned from bovine and human parathyroid glands. The Ca(2+) set-point for the regulation of PTH secretion is right-shifted in primary hyperparathyroidism (1°HPT), but whether there is a similar shift in 2°HPT is unclear. Additionally, the molecular defects associated with such changes in the set-point remain uncharacterized. These experiments were designed to determine (1) if changes in set-point occur in rats with 2°HPT induced by chronic renal insufficiency (CRI) or dietary Ca deficiency, and (2) whether any changes in set-point are mirrored by changes in steady-state mRNA levels for the parathyroid CaR. CaR mRNA levels were quantified in pairs of glands from individual rats using a solution hybridization assay. Blood urea nitrogen and PTH levels were ∼ 4-fold higher in rats with CRI induced by 5/6 nephrectomy 7 weeks earlier. Rats with CRI were also significantly hypocalcemic and hyperphosphatemic. The setpoint was unchanged in CRI rats and CaR mRNA levels were also unaffected. Normal rats fed a 0.02% Ca diet for 6 weeks were markedly hypocalcemic, and had 10- and 15-fold increases in plasma PTH and 1,25-dihydroxyvitamin D(3) levels, respectively. Technical problems prevented assessment of the set-point in these animals, but parathyroid gland CaR mRNA levels were identical in both dietary groups. Thus, neither alterations in mRNA levels for the CaR nor changes in the set-point play demonstrable roles in the pathogenesis of 2°HPT in these models.

Investigation of a fish kill should begin with water quality analysis and use of standard necropsy techniques to rule out the role of parasites or bacteria. The presence of a virus does not mean necessarily that it is a pathogen. Another point to consider is the potential influence of water temperature on pathogenicity; this may be an important factor in developing disease. A list of laboratories that is approved by the USDA to conduct diagnostic testing of aquaculture species can be found at: http://www.aphis.usda.gov/vs/nvsl/labcertification/aquaapplab.htm.

Madison lung carcinoma (M109), a murine tumor of spontaneous origin, appears to be non-immunogenic, according to 2 commonly employed tests for tumor immunogenicity. However, C.parvum-induced immunopotentiation during the growth of M109 tumor results in post-excision anti-tumor immunity to M109 tumor implants. The C.parvum-potentiated post-excision immunity to M109 is tumor-specific and T-cell-dependent. T cells from mice whose progressive M109 tumors have been excised are capable, on passive transfer, of inhibiting adoptive immunotherapy of T-cell-deficient recipients by spleen cells from mice immunized with an admixture of M109 cells and C.parvum. The data are interpreted as evidence supporting the hypothesis that the apparent lack of anti-tumor immunity in this tumor model is not due to the absence of tumor-associated antigens. We suggest that, instead, in this model the balance between the effector and suppressor arms of the immune response favors tumor-induced immunosuppression, resulting in a magnitude of anti-tumor immunity insufficient for detection by commonly employed tests for tumor immunogenicity. Our study shows that shifting the balance in favor of the effector arm by means of immunopotentiation results in a measurable immune response to an apparently non-immunogenic tumor.