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Objective: Cutaneous ulcerative skin lesions in a complex of invasive Gulf of Mexico lionfish (Red Lionfish Pterois volitans, Devil Firefish P. miles, and the hybrid Red Lionfish × Devil Firefish) became epizootic beginning in mid-August 2017. Herein, we provide the first pathological descriptions of these lesions and summarize our analyses to elucidate the etiology of the disease., Methods: We examined ulcerated and normal fish through gross pathology and histopathology, bacterial sampling, and unbiased metagenomic next-generation sequencing. We tracked prevalence of the disease, and we used biological health indicators (condition factor, splenosomatic and hepatosomatic index) to evaluate impacts to health, while considering sex and age as potential risk factors., Result: Typical ulcerative lesions were deep, exposing skeletal muscle, and were bordered by pale or reddened areas often with some degree of scale loss. Only incidental parasites were found in our examinations. Most fish (86%; n = 50) exhibited wound healing grossly and histologically, confirmed by the presence of granulation tissues. A primary bacterial pathogen was not evident through bacterial culture or histopathology. Metagenomic next-generation sequencing did not reveal a viral pathogen (DNA or RNA) but did provide information about the microbiome of some ulcerated specimens. Compared with clinically healthy fish, ulcerated fish had a significantly lower condition factor and a higher splenosomatic index. Disease prevalence at monitored sites through July 2021 indicated that ulcerated fish were still present but at substantially lower prevalence than observed in 2017., Conclusion: Although some common findings in a number of specimens suggest a potential role for opportunistic bacteria, collectively our suite of diagnostics and analyses did not reveal an intralesional infectious agent, and we must consider the possibility that there was no communicable pathogen., (© 2023 The Authors. Journal of Aquatic Animal Health published by Wiley Periodicals LLC on behalf of American Fisheries Society.)

Lead (Pb) free metal halide perovskites by atomistic design are of strong interest to photovoltaics and optoelectronics industries because of the pressing need to resolve Pb-related toxicity and instability challenges. In this study, structural, mechanical, electronic, and optical properties of Pb-free RbSnX 3 (X = Cl, Br, I) perovskites have been evaluated by using ab initio density functional theory (DFT) calculations. The computed elastic constants suggest that the Rb-based halide perovskites are mechanically stable and highly ductile, making them suitable as flexible thin films in optoelectronic devices. Besides, the investigated electronic band structures reveal that the RbSnX 3 compounds are direct bandgap semiconductors, suitable for photovoltaic and optoelectronic applications. Furthermore, several optical parameters such as dielectric functions, reflectivity, photon absorptions, refractive index, optical conductivity, and loss functions have been investigated and the results predict the excellent optoelectronic efficiency of RbSnX 3 . Also, the computed mechanical and optical properties of RbSnX 3 (X = Cl, Br, I) have been compared with the previously studied CsBX 3 (B = Ge, Sn, Pb; X = Cl, Br, I) phases, revealing that the Rb-based perovskites are extremely ductile and possess excellent light absorption and optical conductivity compared to the Cs-based perovskites. Importantly, RbSnI 3 shows superior ductility, absorption coefficient, and optical conductivity compared to the CsBX 3 (B = Ge, Sn, Pb; X = Cl, Br, I) perovskites. Superior absorption at the ultraviolet region of RbSnI 3 holds great promise of this perovskite to be used in next-generation ultraviolet photodetectors., Competing Interests: There are no potential conflicts of interest to be disclosed., (This journal is © The Royal Society of Chemistry.)

Chelonia mydas are primarily herbivorous long-distance migratory sea turtles that contribute to marine ecosystems. Extensive research has been conducted to restore the populations of green turtles. Little is known about their gut microbiota which plays a vital role in their health. We investigated the mucosa-associated bacterial communities across the gastrointestinal (GI) tract of a total four (3, juvenile and 1, adult) stranded green turtles. Samples taken from four GI regions including oesophagus, stomach, small intestine and large intestine were analysed by high-throughput sequencing targeting hypervariable V1-V3 regions of the bacterial 16S rRNA gene. Bacterial diversity and richness decreased longitudinally along the GI tract from oesophagus to the small intestine of stranded turtles. The large intestine showed a higher bacterial diversity and richness compared to small intestine. The bacterial community of green turtles' GI tract was largely dominated by Firmicutes, Proteobacteria, Actinobacteria, Bacteroidetes and Fusobacteria. Aerobic and facultative anaerobic bacteria prevailed primarily in the oesophagus while anaerobes ( Lachnospiraceae , Peptostreptococcaceae and Ruminococcaceae ) constituted the bulk of large intestinal microbiota. Firmicutes dominated the GI tract except within the small intestine where Proteobacteria prevailed. At the OTU level, six percent of the total OTUs (>1% relative abundance) were common in all GI regions. This is a comprehensive characterisation of bacterial microbiota across the GI tract in green turtles which will provide a reference for future studies on turtle gut microbiome and their metabolism to improve their health and nutrition during rehabilitation., Competing Interests: Conflict of interest: The authors declare no conflict of interest., (© 2020 the Author(s), licensee AIMS Press.)

Marine animals represent a dynamic and complex habitat for diverse microbial communities. The microbiota associated with bottlenose dolphins ( Tursiops truncatus ) are believed to influence their health status, but it remains poorly understood. We therefore characterized and compared the bacterial microbiome of bottlenose dolphins from six different anatomical sites that represent four different body systems (respiratory, digestive, reproductive, and integumentary). In this study, a total of 14 free-ranging bottlenose dolphins were sampled during the 2015 Sarasota Bay Dolphin Health Assessment. Bacterial diversity and abundance were assessed by PCR amplification of the hypervariable V3-V4 regions of the bacterial 16S rRNA gene for each sample, followed by sequencing on an Illumina MiSeq platform. Analysis showed that bottlenose dolphins harbor diverse bacterial communities with a unique microbial community at each body system. Additionally, the bottlenose dolphin bacterial microbiome was clearly distinct to the aquatic microbiome from their surrounding habitat. These results are in close agreement with other cetacean microbiome studies, while our study is the first to explore what was found to be a diverse bottlenose dolphin genital microbiome. The core bacterial communities identified in this study in apparently healthy animals might be informative for future health monitoring of bottlenose dolphins., (© 2020 The Author(s).)

Here, we present the complete coding sequences of two tilapia lake virus (TiLV) isolates recovered during an investigation of a mortality event in farmed Nile tilapia in the United States. Phylogenetic analysis supported the isolates as each other's closest relatives and members of a clade of Thai TiLV strains., (Copyright © 2020 Ahasan et al.)

We report the detection and gene coding sequences of three novel Orbivirus species found in six dead farmed white-tailed deer in the United States. Phylogenetic analyses indicate that the new orbiviruses are genetically closely related to the Guangxi, Mobuck, Peruvian horse sickness, and Yunnan orbiviruses, which are thought to be solely borne by mosquitos. However, four of the six viruses analyzed in this work were found as co-infecting agents along with a known cervid pathogen, epizootic hemorrhagic disease virus-2 (EHDV-2), raising questions as to whether the new viruses are primary pathogens or secondary pathogens that exacerbate EHDV-2 infections. Moreover, EHDV-2 is known to be a Culicoides -borne virus, raising additional questions as to whether Culicoides species can also serve as vectors for the novel orbiviruses, if mosquitoes can vector EHDV-2, or whether the deer were infected through separate bites by the insects. Our findings expand knowledge of the possible viral pathogens of deer in the United States. Moreover, due to the close genetic relatedness of the three new orbiviruses to viruses that are primary pathogens of cattle and horses, our findings also underscore a crucial need for additional research on the potential role of the three new orbiviruses as pathogens of other animals.

Mammalian orthoreovirus (MRV) is the type species of the genus Orthoreovirus and causes a range of significant respiratory, nervous or enteric diseases in humans and animals. In 2016 a farmed white-tailed deer (Odocoileus virginianus) fawn became ill, displaying clinical signs of lethargy, dehydration, and profuse foul-smelling diarrhea. A necropsy was performed after the three-week-old fawn died and various tissue samples were submitted to the University of Florida's Cervidae Health Research Initiative for diagnostic evaluation. Aliquots of homogenized heart, liver, and spleen tissues were inoculated onto Vero E6 cells. After virus-specific cytopathic effects (CPE) were detected in Vero cells inoculated with spleen homogenate, infected cells were fixed in glutaraldehyde and analyzed by transmission electron microscopy (TEM), which revealed icosahedral virus particles approximately 75 nm in diameter with morphologies consistent with those of reoviruses within the cytoplasm of the infected cells. RNA extracted from virions in the spent media of infected cells with advanced CPE was used to prepare a cDNA library, which was sequenced using an Illumina MiSeq sequencer. Complete coding sequences for ten separate reovirus segments were attained, and these indicated the isolated agent was a MRV. Genetic and phylogenetic analyses based on the outer capsid sigma-1 (σ1) protein gene sequences supported the Florida white-tailed fawn isolate as a type 2 MRV that branched as the sister group to a MRV-2 strain previously characterized from the urine of a moribund lion (Panthera leo) in Japan. However, analyses based on 7/10 genes (L1-L2, M2-M3, S2-S4) supported the white-tailed deer MRV as the closest relative to a type 3 MRV strain isolated from a dead mink in China. These data suggest the white-tailed deer MRV may have resulted from the natural reassortment of MRVs originating from multiple wildlife species. To our knowledge, this is the first detection of MRV-2 infection in a white-tailed deer. Continued surveillance efforts are needed to determine whether this MRV-2 strain poses a health threat to farmed white-tailed deer populations., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Green turtles are endangered marine herbivorous hindgut fermenters that contribute to a variety of marine ecosystems. Debilitated turtles are often rehabilitated in turtle hospitals. Since accurate diagnosis of disease is difficult, broad-spectrum antibiotics are routinely used as a general treatment, potentially causing collateral damage to the gut microbiome of the patient. Here, we evaluated the concept of the application of bacteriophage (phages) to eliminate targeted intestinal bacteria as an alternative to a broad-spectrum antibiotic (enrofloxacin) in clinically healthy, captive green turtles. Additionally, the impact of a broad-spectrum antibiotic (enrofloxacin) and phage therapy on the gut bacterial communities of green turtles was evaluated. Gut bacterial communities in faecal samples were analysed by sequencing the V1-V3 regions of the bacterial 16S rRNA. Bacteria-specific phage cocktails significantly (P < 0.05) reduced targeted Acinetobacter in phage-treated turtles during the therapy. Compared to control, no significant difference was observed in the bacterial diversity and compositions in phage-treated turtles. In contrast, bacterial diversity was significantly (P < 0.05) reduced in antibiotic-treated turtles at day 15 and throughout the trial. The alteration in the bacterial microbiota of antibiotic-treated turtles was largely due to an increase in abundance of Gram-positive Firmicutes and a concurrent decrease in Gram-negative Bacteroidetes, Proteobacteria and Verrucomicrobia. Additionally, we observed the relative abundance of several bacteria at lower taxonomic level was much less affected by phages than by antibiotics. These data offer the proof of concept of phage therapy to manipulate transient as well as indigenous bacterial flora in gut-related dysbiosis of turtles., (© 2019 Society for Applied Microbiology and John Wiley & Sons Ltd.)

Here, we report the coding sequences of Big Cypress orbivirus isolated from a dead white-tailed deer ( Odocoileus virginianus ) from Florida in 2017. To our knowledge, this is the first detection of Big Cypress orbivirus in a vertebrate host., (Copyright © 2019 Ahasan et al.)

Here, we report the complete genome sequence of mobuck virus isolated from a Florida white-tailed deer (Odocoileus virginianus) in 2017. This is the second report of mobuck virus in the United States and expands the known geographic range of this novel orbivirus into Florida.

Since its discovery in 2014, tilapia lake virus (TiLV) has emerged as a significant cause of mortality in tilapia cultured in Asia, Africa, and South America. Here, we report the complete genome sequence of a TiLV isolate obtained during a diagnostic investigation of an ongoing mortality event involving Nile tilapia cultured in Thailand., (Copyright © 2018 Al-Hussinee et al.)

Here, we report the complete genome sequence of Epizootic hemorrhagic disease virus (EHDV) serotype 6 (EHDV-6), isolated from a Florida white-tailed deer ( Odocoileus virginianus ) in 2016. To our knowledge, this is the first full genome sequence determined for an EHDV-6 isolate from Florida., (Copyright © 2018 Ahasan et al.)

Stranded green turtles (Chelonia mydas) are often cared for in rehabilitation centers until they recover. Although the specific causal agents of diseases in stranded turtles are difficult to diagnose, we know that gut microbiota of green turtles play a vital role in health as well as a wide range of diseases. The objective of this study was to characterize and compare the gut bacterial communities between pre-hospitalization (PH) and post-rehabilitation (PR) stranded green turtles using high-throughput sequencing analysis targeting V1-V3 regions of the bacterial 16S rRNA gene. A total of eight cloacal swab samples were collected from four green turtles undergoing rehabilitation. Proteobacteria dominating in both PH and PR samples without any significant difference. Firmicutes was the second and Bacteroidetes was the third most abundant phylum in PH samples, while Bacteroidetes prevailed in PR samples, followed by Firmicutes. The predominance of the genus Bacteroides in both PH and PR samples indicates the importance of this genus in turtle gut health. At a class level, Epsilonproteobacteria was significantly (P<0.05) associated with PH samples and Deltaproteobacteria predominated (P<0.05) in PR samples. The significant abundance of Campylobacter fetus, Escherichia coli, Clostridium botulinum and Vibrio parahaemolyticus in PH samples indicate pathogenic associations with stranded green turtles with zoonotic potential. The presence of Salmonella enterica in only PR samples suggest possible acquisition of this bacteria during rehabilitation. In this study, all post-rehabilitation green turtles exhibited similar bacterial communities, irrespective of their microbial compositions at pre-hospitalization. The marked differences in the gut bacterial communities of PH and PR turtles indicate the outcome of dietary, management and environmental shift during rehabilitation. Therefore, it is important to address the process of restoring normal gut microbiota of recovered turtles prior to release back to their natural habitat., (Copyright © 2017 Elsevier GmbH. All rights reserved.)

Green turtles (Chelonia mydas) are endangered marine herbivores that break down food particles, primarily sea grasses, through microbial fermentation. However, the microbial community and its role in health and disease is still largely unexplored. In this study, we investigated and compared the fecal bacterial communities of eight wild-captured green turtles to four stranded turtles in the central Great Barrier Reef regions that include Bowen and Townsville. We used high-throughput sequencing analysis targeting the hypervariable V1-V3 regions of the bacterial 16S rRNA gene. At the phylum level, Firmicutes predominated among wild-captured green turtles, followed by Bacteroidetes and Proteobacteria. In contrast, Proteobacteria (Gammaproteobacteria) was the most significantly dominant phylum among all stranded turtles, followed by Bacteroidetes and Firmicutes. In addition, Fusobacteria was also significantly abundant in stranded turtles. No significant differences were found between the wild-captured turtles in Bowen and Townsville. At the family level, the core bacterial community consisted of 25 families that were identified in both the wild-captured and stranded green turtles, while two unique sets of 14 families each were only found in stranded or wild-captured turtles. The predominance of Bacteroides in all groups indicates the importance of these bacteria in turtle gut health. In terms of bacterial diversity and richness, wild-captured green turtles showed a higher bacterial diversity and richness compared with stranded turtles. The marked differences in the bacterial communities between wild-captured and stranded turtles suggest the possible dysbiosis in stranded turtles in addition to potential causal agents., (© FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Ranaviruses were isolated from wild edible frogs ( Pelophylax esculentus ) during epizootics in Denmark and Italy. Phylogenomic analyses revealed that these isolates are closely related and belong to a clade of ranaviruses that includes the Andrias davidianus ranavirus (ADRV), common midwife toad ranavirus (CMTV), Testudo hermanni ranavirus (THRV), and pike-perch iridovirus (PPIV)., (Copyright © 2017 Ariel et al.)

This study investigated Enterobacteriales and their antimicrobial resistance in green sea turtles captured adjacent to the central Great Barrier Reef (GBR) and proximate to urban development. Cloacal swabs were taken from 73 green turtles between 2015 and 2016. A total of 154 out of 341 Gram-negative bacterial isolates were identified as Enterobacteriales that represent 16 different species from 9 different genera. The dominant isolates were Citrobacter (30.52%), Edwardsiella (21.43%) and Escherichia (12.34%). The resistance against 12 antibiotics belonging to 6 different classes was determined. The isolates showed highest resistance to β-lactam antibiotics (78.57%) followed by quinolone (50%) and tetracycline classes (46.1%). Approximately one-third (37.7%) of the isolates identified exhibited multidrug-resistance. Isolates recovered from rehabilitated turtles were significantly multidrug resistant (p<0.009) compared to isolates from other study sites. These results provide baseline information on antimicrobial resistance while revealing gaps for further research to evaluate the level of pollution in the GBR., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

A cross-sectional study was carried out to estimate the true prevalence of Brucella spp. and identify allied risk factors/indicators associated with brucellosis in the Dinajpur and Mymensingh districts of Bangladesh. A total 320 stratified random blood samples were collected and tested in parallel for Brucella antibodies using Rose Bengal (RBT), slow agglutination (SAT), and indirect and competitive ELISA. In addition, a structured questionnaire was administered to each household herd owner to gather information regarding potential risk factors. Both univariate and multivariate logistic regression analyses were used to identify potential risk factors or indicators at animal level. A Bayesian approach was used to estimate the true prevalence of brucellosis along with the test performances (Se and Sp). The estimated animal level true prevalence in cattle was 9.70 % (95 % CPI 5.0-16 %) and in goat 6.3 % (95 % CPI 2.8-11.0 %). The highest sensitivity was achieved by SAT ranges from 69.6 to 78.9 %, and iELISA was found to be more specific (97.4 to 98.8 %) in comparison with other tests. On the other hand, a significant level of (P < 0.05) Brucella seropositivity was found in cattle that breed naturally compared with those that undergo artificial insemination. In goats, exotic breeds were significantly associated (P < 0.05) with Brucella seroprevalence compared with indigenous breeds. Goats with a previous records of abortion and/or retained placenta were also found to have significant levels (P < 0.05). Cows with previous abortion records showed higher odds (18 times) of being seropositive. None of the evaluated tests can be recommended to apply alone for the diagnosis of bovine and caprine brucellosis.