Diagnosis and management of Enterococcus spp infections during rehabilitation of cold-stunned Kemp's ridley turtles (Lepidochelys kempii): 50 cases (2006-2012)

The gut microbiota of wild birds undergoing rehabilitation as a reservoir of multidrug-resistant enterococci in a metropolitan area in Brazil

Enterococci are ubiquitous usually commensal bacteria that can act as opportunistic pathogens frequently associated with resistance to multiple antimicrobial classes. A variety of animals may carry potentially harmful enterococci. In the present work, the occurrence and characteristics of enterococci recovered from the fecal microbiota of wild birds belonging to four families (Accipitridae, Cathartidae, Falconidae and Strigidae) were investigated. Enterococci were recovered from 104 (92.0%) fecal samples obtained from 113 birds, and 260 strains were selected for additional characterization. Enterococcus faecalis was the predominant species (63.8%), followed by Enterococcus hirae (16.2%), Enterococcus faecium (11.5%), Enterococcus gallinarum (5.4%), Enterococcus avium (1.5%), Enterococcus casseliflavus (0.8%), and Enterococcus raffinosus and Enterococcus cecorum (0.4% each). Major percentages (11.9% 75.0%) of nonsusceptibility were observed to quinolones (particularly to enrofloxacin), erythromycin, rifampin, nitrofurantoin, tetracycline and streptomycin. Gentamicin and ampicillin resistances (13.3% each) were only detected among E. faecium. A total of 133 (51.2%) strains were MDR, showing a large variety of MDR profiles, composed by simultaneous resistance encompassing 3 to 12 antimicrobials. MDR strains were found in 68.2% of the birds. Antimicrobial resistance was associated with the presence of the aac(6')-aph(2″)-Ia, aph(2″)-Id, ant(6)-Ia, ant(9)-Ia, ant(9)-Ib, tet(M), tet(L), tet(S), erm(B), mef(A/E), msrC, and vat(D) genes. The most common virulence genes were efaA, gelE, ace, eeP, and asa1. PFGE analysis revealed a large genetic diversity among most of the strains. MLST performed for 35 E. faecalis strains revealed 23 different STs, whereas 14 STs were found among 18 E. faecium strains. Hospital-associated lineages ST22, ST25, ST56, ST1274 were identified. The results show that the wild birds investigated can carry a diversity of potentially hazardous enterococcal strains displaying multiple antimicrobial resistance and virulence genes, reinforcing the assumption that these animals provide an important target to monitor the circulation of microorganisms that deserve consideration under the One Health perspective.

Antimicrobial Pharmacokinetic Studies in Sea Turtles: A Review

Sea turtles face various threats to survival, primarily due to human activities, such as bycatch, vessel strikes, pollution, and climate change. Many of these activities can lead to illness or injuries, increasing the risk of infection. Treating infections appropriately and effectively requires knowledge of antimicrobial properties and their ability to eradicate microbes without harm to the sea turtle. Robust pharmacokinetic studies, therefore, are important for appropriate dosing. Herein, we review the studies detailing the pharmacokinetic properties of antimicrobials in sea turtles conducted to date.

Further Evidence of Anthropogenic Impact: High Levels of Multiple-Antimicrobial-Resistant Bacteria Found in Neritic-Stage Sea Turtles

BACKGROUND/OBJECTIVES

Marine turtles are globally threatened and face daily anthropogenic threats, including pollution. Water pollution from emerging contaminants such as antimicrobials is a major and current environmental concern.

METHODS

This study investigated the phenotypic antimicrobial resistance and heavy metal resistance genes of 47 Vibrio isolates from different stages of sea turtles (oceanic stage vs neritic stage) from the Taiwanese coast.

RESULTS

The results show that a high proportion (48.9%; 23/47) of the Vibrio species isolated from sea turtles in our study had a multiple antimicrobial resistance (MAR) pattern. It was found that Vibrio spp. isolates with a MAR pattern and those with a MAR index value greater than 0.2 were both more likely to be observed in neritic-stage sea turtles. Furthermore, isolates from neritic-stage sea turtles exhibited greater resistance to the majority of antimicrobials tested (with the exception of beta-lactams and macrolides) than isolates from the oceanic-stage groups. Isolates from neritic sea turtles were found to be more resistant to nitrofurans and aminoglycosides than isolates from oceanic sea turtles. Furthermore, isolates with a MAR pattern (p = 0.010) and those with a MAR index value greater than 0.2 (p = 0.027) were both found to be significantly positively associated with the mercury reductase (merA) gene.

CONCLUSIONS

The findings of our study indicate that co-selection of heavy metals and antimicrobial resistance may occur in aquatic bacteria in the coastal foraging habitats of sea turtles in Taiwan.

Synovial fluid analysis in healthy green turtles Chelonia mydas in Taiwan

Septic arthritis is a frustrating disease in sea turtle rehabilitation because of its unclear pathogenesis, delayed onset during rehabilitation, long-term treatment requirements, and potentially poor prognosis. Radiography, blood cultures, and arthrocentesis have been used as diagnostic tools for suspected cases. However, there is currently a lack of data on the characteristics of synovial fluid in healthy sea turtles. To establish reference data for synovial fluid in sea turtles, we enrolled 14 green turtles Chelonia mydas rescued between 2019 and 2022 from 3 facilities using the following inclusion criteria: normal attitude and appetite, normal motor functions of the 4 limbs, no joint swelling, and no ongoing use of antibiotics for at least 1 mo. Bacterial cultures of blood and synovial fluid from the shoulder joints of these turtles were obtained and a qualitative analysis of the synovial fluid was performed. The results revealed bacterial culture-negative blood and synovial fluids at 37°C. Most characteristics of normal synovial fluid in green turtles, such as being transparent, colorless, and able to create a strand of over 2.5 cm by being pulled with a needle in viscosity trials, as well as the cytology of the normal synovial fluids being dominated by histiocytes and synovial lining cells, lymphocytes, and occasionally a few heterophils or erythrocytes were similar to those in mammals. This study provides information on the normal synovial fluid characteristics of green turtles in Taiwan, which may be beneficial for the diagnosis of joint diseases in sea turtles.

AEROBIC BLOOD CULTURES AND COMPARISON TO CLINICAL FINDINGS OF FREE-RANGING GREEN TURTLES (CHELONIA MYDAS) IN EAST CENTRAL FLORIDA

Positive blood cultures have been identified in debilitated, stranded, and deceased green turtles (Chelonia mydas), suggestive of septicemia. Interpretation of these results is often difficult because multiple studies have previously identified bacteremia in clinically healthy reptiles. In this study, paired blood cultures and skin cultures obtained after aseptic preparation of the venipuncture site were collected from 50 immature free-ranging green turtles from Port Canaveral, Florida. Blood culture results were compared with health status (apparently healthy versus unhealthy, based on physical examination findings and appropriate body condition), date of collection, presence of external fibropapillomatosis, healed or unhealed injuries, and presence of barnacles. Weight, body condition score, body condition index, morphometric measures, volume of blood collected, and body temperature were compared between blood culture-positive and blood culture-negative turtles. Positive blood cultures were identified in 14% (7 of 50) of all turtles, including 15.6% (5 of 32) of apparently healthy turtles. Vibrio spp., Bacillus megaterium, Cellulomonas sp., and Staphylococcus pasteuri were isolated in blood culture from apparently healthy individuals. There was a significant association (P = 0.048) between positive skin cultures and positive blood cultures, but isolates obtained were consistently different between paired results. There was no significant association (P > 0.05) between blood culture results and health status, evidence of healed or unhealed injuries, external fibropapillomatosis, or presence of barnacles. Based on the results of this study, positive blood cultures suggestive of nonclinical bacteremia may be present in apparently healthy green turtles. The results of this study will aid the attending clinician in interpretation of blood culture results of apparently healthy or presumed septicemic captive and rehabilitating green turtles as part of the conservation and population recovery of this threatened species.

Antibiotic Resistance of Bacteria Isolated from Clinical Samples and Organs of Rescued Loggerhead Sea Turtles (Caretta caretta) in Southern Italy

Antimicrobial resistance affects all environments, endangering the health of numerous species, including wildlife. Increasing anthropic pressure promotes the acquisition and dissemination of antibiotic resistance by wild animals. Sea turtles, being particularly exposed, are considered sentinels and carriers of potential zoonotic pathogens and resistant strains. Therefore, this study examined the antibiotic resistance profiles of bacteria isolated from loggerhead sea turtles hospitalised in a rescue centre of Southern Italy over a 9-year period. Resistance to ceftazidime, doxycycline, enrofloxacin, flumequine, gentamicin, oxytetracycline and sulfamethoxazole-trimethoprim was evaluated for 138 strains isolated from the clinical samples or organs of 60 animals. Gram-negative families were the most isolated: Vibrionaceae were predominant, followed by Shewanellaceae, Pseudomonadaceae, Enterobacteriaceae and Morganellaceae. These last three families exhibited the highest proportion of resistance and multidrug-resistant strains. Among the three Gram-positive families isolated, Enterococcaceae were the most represented and resistant. The opportunistic behaviour of all the isolated species is particularly concerning for diseased sea turtles, especially considering their resistance to commonly utilised antibiotics. Actually, the multiple antibiotic resistance was higher when the sea turtles were previously treated. Taken together, these findings highlight the need to improve antimicrobial stewardship and monitor antibiotic resistance in wildlife, to preserve the health of endangered species, along with public and environmental health.

RETROSPECTIVE ANALYSIS OF BLOOD CULTURES AND THEIR ASSOCIATION WITH CLINICAL FINDINGS AND OUTCOME IN GREEN SEA TURTLES (CHELONIA MYDAS) AT A FLORIDA SEA TURTLE REHABILITATION FACILITY, 2017-2020

Septicemia is commonly suspected of sea turtles entering rehabilitation. However, blood culture results of green sea turtles (Chelonia mydas) are infrequently reported in the literature. Aerobic blood cultures were performed for intake examinations of 167 green sea turtles undergoing rehabilitation at Brevard Zoo's Sea Turtle Healing Center, Melbourne, Florida, USA from 2017 to 2020. The incidence of positive cultures during intake examinations was 24% (40/167). The most common bacterial isolates identified were Vibrio alginolyticus, Shewanella algae, Achromobacter xylosoxidans, Photobacterium damselae, Sphingomonas paucimobilis, and Vibrio parahaemolyticus. There was a statistically significant association (P < 0.05) between culture status and evidence of external injury. There was no significant association between culture status and Caryospora-like coccidia infection, or fibropapillomatosis. Culture-positive turtles had significantly lower (P < 0.05) total white blood cell, lymphocyte, monocyte, total protein, albumin, and calculated globulin values compared to turtles with negative blood cultures. Significantly more culture-positive turtles died in rehabilitation compared to culture-negative (P = 0.042). Positive blood cultures suggestive of septicemia are commonly found during intake examinations at a Florida sea turtle rehabilitation facility.

Bacterial Infections in Sea Turtles

Sea turtles are important for the maintenance of marine and beach ecosystems, but they are seriously endangered due to factors mainly related to human activities and climate change such as pollution, temperature increase, and predation. Infectious and parasitic diseases may contribute to reducing the number of sea turtles. Bacteria are widespread in marine environments and, depending on the species, may act as primary or opportunistic pathogens. Most of them are able to infect other animal species, including humans, in which they can cause mild or severe diseases. Therefore, direct or indirect contact of humans with sea turtles, their products, and environment where they live represent a One Health threat. Chlamydiae, Mycobacteria, and Salmonellae are known zoonotic agents able to cause mild or severe diseases in sea turtles, other animals, and humans. However, other bacteria that are potentially zoonotic, including those that are antimicrobially resistant, are involved in different pathologies of marine turtles.

Disseminated Candidiasis and Candidemia Caused by Candida palmioleophila in a Green Sea Turtle (Chelonia mydas)

Simple Summary

A sub-adult green sea turtle was rescued and treated for shell fractures on the carapace and plastron. During the first 2 months, the turtle was kept dry-docked with a placement of an intravenous catheter. Pain management, antibiotic and anthelmintic therapy, fluid therapy, human albumin, force feeding, and wound debridement were provided to manage the shell fractures and to control the infection. After 2 months of care, small budding yeasts were noted on the turtle’s blood smears. Blood cultures yielded yeast-like colonies that were later identified as Candida palmioleophila. The patient was then treated with an antifungal agent and the catheter was removed. Approximately 3.5 months later, the carapace and plastron wounds had healed. However, the turtle died at 7.5 months after rescue. The postmortem examination revealed disseminated yeast in joints, bones, brain, and lungs. This study aims to improve the veterinary medical care and, therefore, enhance the conservation of endangered sea turtles by describing a rare report of systemic C. palmioleophila infection.

Abstract

A sub-adult green sea turtle (Chelonia mydas) was rescued and treated for carapace and plastron shell fractures. The turtle was kept dry-docked for the first 2 months with a placement of a long-term jugular central venous catheter (CVC). Pain management, aggressive antibiotic and anthelmintic therapy, fluid therapy, force feeding, and wound debridement were provided to manage the shell fractures and control bacteremia. Human albumin was administered to treat severe hypoalbuminemia. On day 59, small budding yeasts were noted on the blood smears. Candidemia was confirmed by blood culture, as the yeasts were identified as Candida palmioleophila by the molecular multi-locus identification method. The CVC was removed, and the patient was treated with itraconazole. Although the carapace and plastron wounds had epithelized by 5.5 months after the rescue, the turtle died unexpectedly by 7.5 months. The postmortem examination revealed numerous necrogranulomas with intralesional yeasts, morphologically compatible with Candida spp., in joints, bones, brain, and lungs, suggestive of disseminated candidiasis. We describe a rare case of candidemia in the veterinary field. To our knowledge, this is the first report of candidiasis caused by C. palmioleophila in a reptile. The present results should improve veterinary medical care and, therefore, enhance the conservation of endangered sea turtle species.

Osteomyelitis in cold-stunned Kemp's ridley sea turtles (Lepidochelys kempii) hospitalized for rehabilitation: 25 cases (2008-2018)

OBJECTIVE

To characterize osteolytic lesions in cold-stunned Kemp's ridley sea turtles (Lepidochelys kempii) hospitalized for rehabilitation and describe methods used for the management of such lesions.

ANIMALS

25 stranded, cold-stunned Kemp's ridley sea turtles hospitalized between 2008 and 2018.

PROCEDURES

Medical records of sea turtles with a diagnosis of osteolytic lesions were reviewed retrospectively to obtain the date of diagnosis, clinical signs, radiographic findings, microbial culture results, hematologic and plasma biochemical data, cytologic and histologic findings, antimicrobial history, time to first negative culture result, treatment duration, and outcome.

RESULTS

Lesions were identified radiographically a median of 50 days after admission and were located within epiphyses or metaphyses of various appendicular joints. Lesions were associated with periarticular swelling (n = 24), lameness (16), lethargy (2), and hyporexia (2). Bacterial culture yielded growth of single organisms (n = 16), multiple organisms (2), or no growth (6). Significant differences in hematologic and biochemical data were detected between the times of diagnosis and convalescence. Cytologic and histologic findings characterized the lesions as osteomyelitis leading to septic arthritis. Sixteen sea turtles were managed medically, and 8 were managed medically and surgically. Surgery resulted in rapid improvement in joint mobility and overall clinical status. Most (22/25 [88%]) sea turtles survived and were released after long-term management.

CONCLUSIONS AND CLINICAL RELEVANCE

During rehabilitation, cold-stunned Kemp's ridley sea turtles may be affected by osteomyelitis. Medical management based on antimicrobial susceptibility testing was effective for most turtles. Long term management efforts in turtles are justified by high survival rate.

Evaluation of the Respiratory Microbiome and the Use of Tracheal Lavage as a Diagnostic Tool in Kemp's Ridley Sea Turtles (Lepidochelys kempii)

Simple Summary

A tracheal lavage is commonly used to characterize the microbes that may be causing pneumonia in sea turtles, typically by culture-dependent methods. In this study, we characterized the tracheal lavage microbiome through culture-independent methods and compared the resulting sequence data to conventional cultures, the degree of radiographic lung abnormalities, and pathogens of sea turtles as previously reported in the literature. This study also evaluates the microbial communities at different sections of the respiratory tract from deceased sea turtles. We found that radiographic lung abnormalities do not correlate with the tracheal lavage microbiome, tracheal lavage cultures under-represent the microbial community as determined by culture-independent methods, many previously reported sea turtle pathogens are present in low abundance of the tracheal lavage microbiome, and tracheal lavages are not representative of other sections of the respiratory tract.

Abstract

Respiratory disease is a common cause of morbidity and mortality in sea turtles, including the Kemp’s ridley sea turtle (Lepidochelys kempii). Although culture-dependent methods are typically used to characterize microbes associated with pneumonia and to determine treatment, culture-independent methods can provide a deeper understanding of the respiratory microbial communities and lead to a more accurate diagnosis. In this study, we characterized the tracheal lavage microbiome from cold-stunned Kemp’s ridley sea turtles at three time points during rehabilitation (intake, rehabilitation, and convalescence) by analyzing the 16S rRNA gene collected from tracheal lavage samples. We retrospectively developed a radiographic scoring system to grade the severity of lung abnormalities in these turtles and found no differences in diversity or composition of microbial communities based on radiographic score. We also found that the culture isolates from tracheal lavage samples, as well as other previously reported sea turtle pathogens, were present in variable abundance across sequenced samples. In addition to the tracheal microbial community of live turtles, we characterized microbial communities from other segments of the respiratory tract (glottis, trachea, anterior lung, posterior lung) from deceased turtles. We found a high degree of variability within turtles and a high degree of dissimilarity between different segments of the respiratory tract and the tracheal lavage collected from the same turtle. In summary, we found that the pulmonary microbial community associated with pneumonia in sea turtles is complex and does not correlate well with the microbial community as identified by tracheal lavage. These results underscore the limitations of using tracheal lavage for identification of the causative agents of pneumonia in sea turtles.

Uncovering the genomic and metagenomic research potential in old ethanol-preserved snakes

Natural history museum collections worldwide represent a tremendous resource of information on past and present biodiversity. Fish, reptiles, amphibians and many invertebrate collections have often been preserved in ethanol for decades or centuries and our knowledge on the genomic and metagenomic research potential of such material is limited. Here, we use ancient DNA protocols, combined with shotgun sequencing to test the molecular preservation in liver, skin and bone tissue from five old (1842 to 1964) museum specimens of the common garter snake (Thamnophis sirtalis). When mapping reads to a T. sirtalis reference genome, we find that the DNA molecules are highly damaged with short average sequence lengths (38-64 bp) and high C-T deamination, ranging from 9% to 21% at the first position. Despite this, the samples displayed relatively high endogenous DNA content, ranging from 26% to 56%, revealing that genome-scale analyses are indeed possible from all specimens and tissues included here. Of the three tested types of tissue, bone shows marginally but significantly higher DNA quality in these metrics. Though at least one of the snakes had been exposed to formalin, neither the concentration nor the quality of the obtained DNA was affected. Lastly, we demonstrate that these specimens display a diverse and tissue-specific microbial genetic profile, thus offering authentic metagenomic data despite being submerged in ethanol for many years. Our results emphasize that historical museum collections continue to offer an invaluable source of information in the era of genomics.

Antimicrobial Resistance in Loggerhead Sea Turtles (Caretta caretta): A Comparison between Clinical and Commensal Bacterial Isolates

Simple Summary

Gram negative organisms are frequently isolated from Caretta caretta and may contribute to the dissemination of antimicrobial resistance. In this study, commensal bacteria isolated from oral and cloacal samples of 98 healthy C. caretta were compared to clinical isolates isolated from the wounds of 102 injured animals, in order to investigate the presence of antimicrobial resistance bacteria in free-living loggerheads from the Adriatic Sea. A total of 410 bacteria were cultured and differences were noted in the isolated genera, as some of them were isolated only in healthy animals, while others were isolated only from injured animals. When tested for susceptibility to antimicrobials, clinical isolates showed highly significant differences in the antimicrobial resistance rates vs. commensal isolates for all the drugs tested, except for doxycycline. The detection of high antimicrobial resistance rates in loggerhead sea turtles is of clinical and microbiological significance since it impacts both the choice of a proper antibiotic therapy and the implementation of conservation programs.

Abstract

Gram negative organisms are frequently isolated from Caretta caretta turtles, which can act as reservoir species for resistant microorganisms in the aquatic environment. C. caretta, which have no history of treatment with antimicrobials, are useful sentinel species for resistant microbes. In this culture-based study, commensal bacteria isolated from oral and cloacal samples of 98 healthy C. caretta were compared to clinical isolates from the wounds of 102 injured animals, in order to investigate the presence of AMR bacteria in free-living loggerheads from the Adriatic Sea. A total of 410 isolates were cultured. Escherichia coli and genera such as Serratia, Moraxella, Kluyvera, Salmonella were isolated only in healthy animals, while Acinetobacter, Enterobacter, Klebsiella and Morganella were isolated only from the wounds of the injured animals. When tested for susceptibility to ampicillin, amoxicillin + clavulanic acid, ceftazidime, cefuroxime, gentamicin, doxycycline, ciprofloxacin and enrofloxacin, the clinical isolates showed highly significant differences in AMR rates vs. commensal isolates for all the drugs tested, except for doxycycline. The detection of high AMR rates in loggerheads is of clinical and microbiological significance since it impacts both the choice of a proper antibiotic therapy and the implementation of conservation programs.

Antibiotic-Resistant Bacteria in Green Turtle (Chelonia mydas) Rearing Seawater

Simple Summary

The Sea Turtle Conservation Center of Thailand (STCCT) has conducted an early intervention program for conservation and faced high mortality rates due to bacterial diseases. Our previous investigation of juvenile turtle carcasses and sea water in the turtle hold tanks implied an association between bacterial isolates in rearing water and infection in captive turtles. In this study, for a management plan of juvenile sea turtles with bacterial infection, we monitored antibiotic resistance of bacteria in seawater from juvenile green turtle holding tanks at STCCT in three periods: January 2015 to April 2016, January to April 2018, and January to April 2019. The results clearly indicated that numbers of resistant bacteria and antibiotics were increased. Assessment of resistance against ten antibiotics revealed high prevalence of antibiotic-resistant bacteria to the beta-lactam class (ampicillin, penicillin, and cefazolin), whereas low resistant isolate numbers were found to aminoglycosides. From the results of this study, we suggest that antibiotic-resistant bacterial assessment in sea turtle rearing seawater will provide important information for the treatment of bacteria-infected sea turtles in husbandry.

Abstract

Antibiotic resistance of microorganisms is a serious health problem for both humans and animals. Infection of these bacteria may result in therapy failure, leading to high mortality rates. During an early intervention program process, the Sea Turtle Conservation Center of Thailand (STCCT) has faced high mortality rates due to bacterial infection. Previously, investigation of juvenile turtle carcasses found etiological agents in tissue lesions. Further determination of sea water in the turtle holding tanks revealed a prevalence of these causative agents in water samples, implying association of bacterial isolates in rearing water and infection in captive turtles. In this study, we examined the antibiotic resistance of bacteria in seawater from the turtle holding tank for a management plan of juvenile turtles with bacterial infection. The examination was carried out in three periods: 2015 to 2016, 2018, and 2019. The highest isolate numbers were resistant to beta-lactam, whilst low aminoglycoside resistance rates were observed. No gentamicin-resistant isolate was detected. Seventy-nine isolates (71.17%) were resistant to at least one antibiotic. Consideration of resistant bacterial and antibiotic numbers over three sampling periods indicated increased risk of antibiotic-resistant bacteria to sea turtle health. Essentially, this study emphasizes the importance of antibiotic-resistant bacterial assessment in rearing seawater for sea turtle husbandry.

Characterization of oral and cloacal microbial communities in cold-stunned Kemp's ridley sea turtles (Lepidochelys kempii) during the time course of rehabilitation

Microbial communities of animals play a role in health and disease, including immunocompromised conditions. In the northeastern United States, cold-stunning events often cause endangered Kemp's ridley turtles (Lepidochelys kempii) to become stranded on beaches in autumn. These sea turtles are admitted to rehabilitation facilities when rescued alive and are presumed immunocompromised secondary to hypothermia. To better understand the role that microbes play in the health of cold-stunned sea turtles, we characterized the oral and cloacal microbiome from Kemp's ridley turtles at multiple timepoints during rehabilitation, from admission to pre-release, by using Illumina sequencing to analyze the 16S rRNA gene. Microbial communities were distinct between body sites and among turtles that survived and those that died. We found that clinical parameters such as presence of pneumonia or values for various blood analytes did not correlate with oral or cloacal microbial community composition. We also investigated the effect of antibiotics on the microbiome during rehabilitation and prior to release and found that the type of antibiotic altered the microbial community composition, yet overall taxonomic diversity remained the same. The microbiome of cold-stunned Kemp's ridley turtles gradually changed through the course of rehabilitation with environment, antibiotics, and disease status all playing a role in those changes and ultimately the release status of the turtles.

Antimicrobial-resistance profiles of gram-negative bacteria isolated from green turtles (Chelonia mydas) in Taiwan

The green turtle (Chelonia mydas) is listed as a globally endangered species and is vulnerable to anthropogenic threats, including environmental pollution. This study investigated the antimicrobial resistance of Gram-negative bacteria isolated from wild green turtles admitted to a sea turtle rehabilitation center in Taiwan. For this investigation, cloacal and nasal swab samples were collected from 28 green turtles between 2018 and 2020, from which a total of 47 Gram-negative bacterial isolates were identified. Among these, Vibrio spp. were the most dominant isolate (31.91%), and 89.36% of the 47 isolates showed resistance to at least one of 18 antimicrobial agents tested. Isolates resistant to one (6.38%), two (8.51%), and multiple (74.47%) antimicrobials were observed. The antimicrobial agents to which isolates showed the greatest resistance were penicillin (74.47%), followed by spiramycin, amoxicillin, and cephalexin. The antimicrobial-resistance profiles identified in this study provide useful information for the clinical treatment of sea turtles in rehabilitation facilities. The results of our study also imply that wild green turtles may be exposed to polluting effluents containing antimicrobials when the turtles traverse migratory corridors or forage in feeding habitats. To benefit sea turtle conservation, future research should focus on (1) how to prevent pollution from antimicrobials in major green turtle activity areas and (2) identifying sources of antimicrobial-resistant bacterial strains in coastal waters of Taiwan.

Steatitis in Cold-Stunned Kemp's Ridley Sea Turtles (Lepidochelys kempii)

The pathogenesis of steatitis that infrequently occurs in cold-stunned Kemp's ridley sea turtles (KRT; Lepidochelys kempii) has been undetermined. The objectives of this study were to investigate the clinical (n = 23) and histologic findings (n = 11) in cold-stunned KRT, and to compare plasma concentrations of α-tocopherol (vitamin E), thiobarbituric acid reactive substances (TBARS), and the TBARS to vitamin E (T/E) ratio (an assessment of oxidative stress) between cold-stunned KRT with clinically and/or histologically confirmed steatitis (n = 10) and free-ranging KRT (n = 9). None of the cold-stunned turtles had clinically detectable steatitis at admission, and the median number of days to diagnosis of steatitis was 71 (range 33-469). Histologic findings of affected adipose tissue included heterophilic (n = 9) and/or histiocytic (n = 5) steatitis, fat necrosis (n = 7), myonecrosis (n = 2), and intralesional bacteria (n = 6). Cold-stunned KRT had significantly lower plasma vitamin E concentrations (median = 3.5 nmol/g), lower plasma TBARS concentrations (median = 1.6 nmol/g), and higher T/E ratios (median = 0.37), than controls (208.8 nmol/g; 2.1 nmol/g; 0.01, respectively). These results suggest a multifactorial etiology for the development of steatitis in KRT during rehabilitation, including tissue injury, septicemia, and various factors resulting in imbalances of anti-/oxidative status. By highlighting the need to provide more effective vitamin E supplementation, and the need to re-assess specific components of the diet, this study may lead to reduced incidence and improved medical management of steatitis in cold-stunned sea turtles.

Diagnosis and Treatment of Pulmonary Disease in Sea Turtles (Caretta caretta)

The aim of this study was to describe the clinical signs, radiographic, endoscopic and CT findings, cytological and microbiological findings and treatments of pulmonary diseases in sea turtles, in order to obtain an accurate diagnosis that avoids unnecessary therapy and antibiotic-resistance phenomena. In total, 14 loggerheads (Caretta caretta), with clinical and/or radiographic findings of pulmonary pathology, were assessed through various combinations of clinical, radiological, CT, endoscopic examination and bronchoalveolar lavage, which recovered fluid for cytologic and microbiologic analysis. In all cases, radiographic examination led to a diagnosis of pulmonary disorders-4 unilateral and 10 bilateral. All bacteria cultured were identified as Gram-negative. Antibiotic resistance was greater than 70% for all beta-lactams tested. In addition, all bacterial strains were 100% resistant to colistin sulfate and tetracycline. Specific antibiotic therapies were formulated for seven sea turtles using Enrofloxacin, and for four sea turtles using ceftazidime. In two turtles, antibiotic therapy was not included due to the presence of antibiotic resistance against all the antibiotics evaluated. In both cases, the coupage technique and environmental management allowed the resolution of the lung disease without antibiotics. All 14 sea turtles were released back into the sea. Radiographic examination must be considered the gold standard for screening sea turtles that show respiratory signs or abnormal buoyancy. Susceptibility testing with antimicrobials allowed appropriate therapy, including the reduction of antibiotic-resistance.

Ameliorating transport-related stress in endangered Kemp's ridley sea turtles (Lepidochelys kempii) with a recovery period in saltwater pools

Sea turtle rehabilitation clinics and aquaria frequently transport stranded sea turtles long distances out of water, e.g. for release at sites with appropriate water temperatures. Endangered Kemp's ridley turtles (Lepidochelys kempii) are known to exhibit an adrenal stress response during such transports. In an opportunistic study of turtles transported by road from Massachusetts to Georgia for release, we tested whether placing turtles in saltwater pools for short periods after transport would help turtles recover from transport-related stress. Eighteen juvenile Kemp's ridley turtles were examined and blood samples collected (1) immediately pre-transport, (2) immediately post-transport and (3) after a 6 h (n = 9) or 24 h (n = 9) post-transport period in unfamiliar pools, after which all turtles were released to the sea. Blood samples were analyzed for corticosterone, glucose, total white blood cell (WBC) count, heterophil/lymphocyte (H/L) ratio, pH, pO₂, pCO₂, HCO₃ (bicarbonate), sodium, potassium, ionized calcium, lactate and hematocrit. Though the majority of turtles remained in good clinical condition, corticosterone, glucose, WBC and H/L elevated significantly during transport, while potassium declined slightly but significantly. After at least 6 h in a saltwater pool, potassium and glucose returned to pre-transport baselines and corticosterone partially recovered toward baseline. Extending the pool time to 24 h did not markedly enhance the physiological recovery of turtles, and two immune measures (WBC, H/L) remained elevated from the effect of transport. Six hours in a saltwater pool appears to facilitate the recovery of Kemp's ridley sea turtles from transport-related stress and may therefore improve their readiness for release.

Aeromonas induced polyostotic osteomyelitis in a juvenile loggerhead sea turtle Caretta caretta

Bacterial bone infections have been occasionally reported in wild sea turtles. This study reports on a sub-adult Caretta caretta affected by Aeromonas hydrophila osteomyelitis, with extensive involvement of cranial and caudal flippers. The turtle was severely debilitated, had limited flipper mobility and showed signs of pain in reaction to manipulation. Radiographs and computed tomography revealed multiple lytic bone lesions. Since an infectious polyostotic osteomyelitis was suspected, the turtle was subjected to echo-assisted fine needle aspiration to characterize the etiology of the disease. Bacterial cultures and antibiotic susceptibility testing led to the isolation of Aeromonas hydrophila responsive to amikacin and doxycycline. Therefore, the turtle was treated with these antibiotics and monitored through repeat bacterial cultures and diagnostic imaging. The turtle was released 17 mo after admission, upon resolution of clinical signs. The documentation of this case provides a treatment approach that may improve the outcome of Aeromonas-associated osteomyelitis, especially in endangered wildlife species.

Management of Polyarthritis Affecting Sea Turtles at Kélonia, the Reunion Island Sea Turtle Observatory (2013-17)

All sea turtle species are listed on the Red List of the International Union for the Conservation of Nature due to multiple threats. Among these, disease is a frequent cause of stranded sea turtles encountered in rehabilitation centers. Since 2013, we found joint swelling in 13 sea turtles belonging to all four sea turtle species submitted to the Kélonia Sea Turtle Observatory of Reunion Island, France. Affected sea turtles presented with lameness, anorexia, and lethargy. Polyarthritis was radiographically confirmed and lesions were characterized by progressive osteolysis of bones surrounding joints. Anterior flippers were affected in all cases and posterior flippers were also involved in some cases. We isolated several bacterial agents from blood and synovial fluid. We attempted a collective treatment with injectable florfenicol, based on sensitivity results, which was continued for 4 wk and then as needed based on radiographic evolution of the lesions. Radiographic stabilization of the lesions occurred in nine of 13 cases. We reviewed environmental conditions and optimized them to minimize stress that could predispose these rehabilitated sea turtles to opportunistic infections. Handling techniques used to move sea turtles were also improved. While we can make no conclusion regarding the cause of polyarthritis in this population of sea turtles, we successfully managed this poorly described problem in a rehabilitation setting.

Emergent multisystemic Enterococcus infection threatens endangered Christmas Island reptile populations

Multisystemic infections with a morphologically unusual bacterium were first observed in captive critically endangered Lister’s geckos (Lepidodactylus listeri) on Christmas Island in October 2014. Since then the infection was identified in another captive critically endangered lizard species, the blue-tailed skink (Cryptoblepharus egeriae) and two species of invasive geckos; the four clawed gecko (Gehyra mutilata) and Asian house gecko (Hemidactylus frenatus), in a wide geographic range across the east side of the island. The Gram and periodic acid-Schiff positive cocci to diplococci have a propensity to form chains surrounded by a matrix, which ultrastructurally appears to be formed by fibrillar capsular projections. The bacterium was associated with severe and extensive replacement of tissues, but minimal host inflammatory response. Attempts to grow the organism in culture and in embryonated eggs were unsuccessful. Molecular characterisation of the organism placed it as a novel member of the genus Enterococcus. Disease Risk Analyses including this organism should now be factored into conservation management actions and island biosecurity.

TISSUE ENZYME ACTIVITIES IN KEMP'S RIDLEY TURTLES (LEPIDOCHELYS KEMPII)

This study determined the tissue distribution and activities of eight enzymes in 13 juvenile Kemp's ridley turtles (Lepidochelys kempii) that died after stranding. Samples from the liver, kidney, skeletal muscle, cardiac muscle, pancreas, lung, small intestine, and spleen were evaluated for activities of alanine aminotransferase (ALT), alkaline phosphatase (ALP), amylase, aspartate aminotransferase (AST), creatine kinase (CK), γ-glutamyl transferase (GGT), lactate dehydrogenase (LDH), and lipase. AST, CK, and LDH activities were highest in cardiac and skeletal muscle but were also found in all other tissues. Amylase and lipase activities were highest in the pancreas and low in all other tissues. ALP activity was highest in the lung. ALT activity was highest in liver, kidney, and cardiac muscle, and GGT activity was highest in the kidney, but activities of these enzymes were low in all tissues. These data may assist clinicians in interpretation of plasma enzyme activities of Kemp's ridley turtles.