Deborah B. Pouder

Survey of Ovaprim Use as a Spawning Aid in Ornamental Fishes in the United States as Administered through the University of Florida Tropical Aquaculture Laboratory

Abstract Ovaprim is a commercial product used as a spawning aid in fishes and contains a salmon gonadotropin-releasing hormone analog and a dopamine antagonist. Since 2005, the use of Ovaprim in commercial ornamental fish production has been through enrollment with the University of Florida Tropical Aquaculture Laboratory in an Investigational New Animal Drug (INAD) study. A database is maintained to provide information to the U.S. Food and Drug Administration on product effectiveness and target animal safety. There were 25 fish species in 17 genera and 10 families in the INAD database. Ostariophysan fishes constituted 84% of the species and 99.9% of the individuals. The goldfish Carassius auratus was numerically the dominant species (80% of individuals). Nearly 40,000 fish in total were injected with Ovaprim; ovulation was induced in 92% of females and spermiation was induced in 96% of males, primarily reflecting extensive use in cyprinid fishes. Conversely, average success rates across all species were ...

Occurrence of Piscirickettsiosis-Like Syndrome in Tilapia in the Continental United States

From 2001 to 2003, tilapia (Oreochromis sp.) farms in Florida, California, and South Carolina experienced epizootics of a systemic disease causing mortality. The fish exhibited lethargy, occasional exophthalmia, and skin petechia. The gills were often necrotic, with a patchy white and red appearance. Grossly, the spleen and kidneys were granular with whitish irregular nodules throughout. Granulomatous infiltrates were observed in kidney, spleen, testes, and ovary tissues, but not in the liver. The granulomas contained pleomorphic coccoid bacteria, measuring 0.57 ± 0.1 × 0.8 ± 0.2 μm, that were Giemsa-positive, acid-fast-negative, and Gram-negative. The bacteria had a double cell wall, variable electron-dense and -lucent areas, and were present in the cytoplasm and within phagolysosomes. The syndrome was associated with cold stress and poor water conditions. These findings are consistent with an infectious process caused by a Piscirickettsia-like bacterium described previously in tilapia in Taiwan and Hawaii. This report involves the first identified cases of a piscirickettsiosis-like syndrome affecting tilapia in the continental United States.

Molecular and immunohistochemical diagnosis of Francisella noatunensis subsp. orientalis from formalin-fixed, paraffin-embedded tissues

Members of the genus Francisella (viz., F. noatunensis subsp. orientalis [Fno] and F. noatunensis subsp. noatunensis) have been described as causative agents of chronic granulomatous and pyogranulomatous lesions in wild and cultured fish species. In the present study, 68 archived formalin-fixed, paraffin-embedded (FFPE) tissues from several fish species, collected at different geographical locations from 2000 to 2011, were analyzed using a real-time polymerase chain reaction assay for the detection of the Fno intracellular growth loci C (iglC) gene and by immunohistochemistry for the demonstration of Fno antigens. The results revealed a high correlation between these 2 diagnostic techniques validating their use for the diagnosis of Fno infection in archived FFPE tissues and confirming the presence of Fno in fish species from the Cari y years of the present century.

Association of Mycobacteria in Recirculating Aquaculture Systems and Mycobacterial Disease in Fish

Mycobacterium marinum isolates cultivated from tissue containing granulomatous lesions in Florida pompano Trachinotus carolinus and from biofilm samples collected from their tank and water recirculating system had identical (L1 of 11 bands) repetitive-sequence-based polymerase chain reaction (rep-PCR) DNA fingerprints. A second M. marinum clone sharing 4 of 11 rep-PCR bands with the first clone was isolated from some fish tissues but not from system samples. Water samples yielded low numbers of colonies of mycobacteria (0.08-1.3/mL), but high numbers were recovered from biofilms (260-12,000/swab) and filters (63-21,000/ filter). Mycobacterium hemophilum, M. chelonae, M. trivale, M. gastri, and M. gordonae were isolated from system samples alone.

IDENTIFICATION OF FRANCISELLA NOATUNENSIS IN NOVEL HOST SPECIES FRENCH GRUNT (HAEMULON FLAVOLINEATUM) AND CAESAR GRUNT (HAEMULON CARBONARIUM)

Abstract:u2003 Francisella noatunensis is an emerging pathogen of fish that has been isolated from several cultured species worldwide. Here presented is a case involving several hundred marine grunts that were caught near the Florida Keys for display in public aquaria. These fish were maintained in a recirculating system where they began to experience mortalities approximately two weeks post-stocking. Postmortem examination revealed disseminated systemic granulomatous disease most severely affecting spleen and kidney. Splenic and renal tissue homogenates inoculated in modified Thayer Martin agar media yielded colonies consistent with F. noatunensis 4 days post inoculation. Bacterial colonies and tissues were confirmed positive after real-time PCR amplification of the intracellular growth loci gene (iglC) specific for F. noatunensis subspecies orientalis. Consequently, multiple novel host species for this pathogen were identified, including the French grunt (Haemulon flavolineatum) and the Caesar grunt (Haemulon carbonarium).

New disease records for hatchery-reared sturgeon. II. Phaeohyphomycosis due to Veronaea botryosa

A series of fungal cases in hatchery-reared juvenile and young adult Siberian sturgeon Acipenser baerii and white sturgeon A. transmontanus occurred at production facilities in Florida and California, USA, respectively. Affected fish exhibited abnormal orientation and/or buoyancy, emaciation, coelomic distension, exophthalmos, cutaneous erythema, and ulcerative skin and eye lesions. Necropsies revealed haemorrhage throughout the coelom, serosanguinous coelomic effusion and organomegaly with nodular or cystic lesions in multiple organs. Fungal hyphae were observed in 27 fish (24 A. baerii and 3 A. transmontanus) via microscopic examination of tissue wet mounts and on slides prepared from colonies grown on culture media. Histopathological examination of these infected tissues revealed extensive infiltration by melanised fungal hyphae that were recovered in culture. Phenotypic characteristics and sequencing of the fungal isolates with the use of the internal transcribed spacer region and 28S rRNA gene confirmed the aetiological agent as Veronaea botryosa. To our knowledge, this is the first documentation of V. botryosa infection in fish, although melanised fungi of the closely related genus Exophiala are well-known pathogens of freshwater and marine fishes.

Establishing a Diagnostic Technique for Coelomocentesis in the Long-Spined Sea Urchin Diadema antillarum

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 diagnostic quality of the sample utilizing diagnostic imaging, (2) identify coelomic fluid bacterial isolates (using Biolog GEN III MicroLog and 16s rDNA sequencing), and (3) compare positive cultures to animal weight, holding time prior to sampling, water temperature, and gross fluid appearance. Seventy Diadema antillarum from the Florida Keys collected in two groups (March and September 2015) were utilized. Positive cultures for bacterial contamination were identified in 5% and 44%, respectively, of animals in the sampling groups. Vibrio spp. was the predominant genus identified. Positive cultures were more frequent in the group with smaller-sized animals, increased holding times, and elevated water temperatures. Deviation from clear-pink gross coelomic fluid appearance did not reliably predict bacterial contamination. A standardized technique for coelomocentesis was defined. The use of the proposed coelomocentesis methodology may facilitate improved health evaluations of sea urchins and may be applicable to research, conservation efforts, and disease investigations.

Preliminary Evaluation of Gulf Sturgeon Production and Sustainability of a Zero-Discharge Pond Water Recirculating Tank System

Abstract Given increasing interest in zero-discharge aquaculture systems, we conducted a preliminary 17-month production study of Gulf sturgeon Acipenser oxyrinchus desotoi in a recirculating pond water (RPW) system and a traditional flow-through well water (FTW) system. Both systems had three 6.1-m-diameter tanks stocked with 400 fish (7 g/fish). In the RPW system, water was pumped from a baffled pond containing aquatic macrophytes into the culture tanks and was then gravity discharged back to the pond. Production and feed conversion ratio were better in the FTW system (778 kg/tank and 1.8) than in the RPW system (494 kg/tank and 2.0). Survival was not significantly different between systems (>93%). The RPW tanks had more extreme fluctuations in temperature (7–34°C) than did FTW tanks (19–23°C). The baffled pond seemed beneficial in increasing dissolved oxygen and decreasing ammonia concentrations relative to the RPW tank water. In addition, the RPW system had the advantage of zero discharge. For the FTW...