Pyrethroid-associated nephrotoxicity in channel catfish, Ictalurus punctatus, and blue catfish, I. furcatus, at a public aquarium.

Over the course of an approximately 11-month period, an outdoor, freshwater, mixed species, recirculating, display system at a public aquarium experienced intermittent mortalities of channel catfish (Ictalurus punctatus) and blue catfish (I. furcatus). Catfish acutely presented for abnormal buoyancy, coelomic distention, and protein-rich coelomic effusion. Gross lesions typically involved massive coelomic distension with protein-rich effusion, generalized edema, and gastric hemorrhage and edema. Microscopically, primary lesions included renal tubular necrosis, gastric edema with mucosal hemorrhages, and generalized edema. Aerobic culture and virus isolation could not recover a consistent infectious agent. Intracoelomic injection of coelomic effusion and aspirated retrobulbar fluid from a catfish into naïve zebrafish (bioassay) produced peracute mortality in 3 of 4 fish and nervous signs in the fourth compared with 2 saline-injected control zebrafish that had - no mortality or clinical signs. Kidney tissue and coelomic effusion were submitted for gas chromatography tandem mass spectrometry by multiple reaction monitoring against laboratory standards, which detected the presence of multiple pyrethroid toxins, including bioallethrin, bifenthrin, trans-permethrin, phenothrin, and deltamethrin. Detection of multiple pyrethroids presumably reflects multiple exposures with several products. As such, the contributions of each pyrethroid toward clinical presentation, lesion development, and disease pathogenesis cannot be determined, but they are suspected to have collectively resulted in disrupted osmoregulation and fluid overload due to renal injury. Pesticide-induced toxicoses involving aquarium fish are rarely reported with this being the first description of pyrethroid-induced lesions and mortality in public aquarium-held fish.

Establishment of a 2-dimensional echocardiographic protocol and reference parameters for clinically healthy southern stingrays (Hypanus americanus).

OBJECTIVE: To establish an echocardiographic technique and 2-dimensional reference parameters for southern stingrays (Hypanus americanus). A second objective was to compare echocardiographic measurements obtained from animals of different sex, size, environment, handling technique, and position. ANIMALS: 84 presumed healthy, wild, semiwild, and aquarium-housed southern stingrays. PROCEDURES: Animals, anesthetized and manually restrained, were positioned in dorsal recumbency, and echocardiography was performed. A subset of this population was also imaged in ventral recumbency for comparison. RESULTS: Echocardiography was feasible, and reference parameters were established for this species. While some standard measurements could not be assessed due to body habitus, all valves, chambers, and the conus were clearly visualized in the majority of animals. Statistical significance was reached for some variables when comparing animals from different environments and handling methods, but these differences were not considered clinically relevant. The data were therefore separated into 2 subsets of echocardiographic reference parameters based on disc width since some of the measurements were dependent on body size. This approach mostly separated the sexes due to strong sexual dimorphism. CLINICAL RELEVANCE: Limited information is available regarding cardiac disease in elasmobranchs; most of the available information on cardiac physiology focuses on a few shark species. Two-dimensional echocardiography is a noninvasive tool utilized to evaluate cardiac structure and functionality. Southern stingrays are one of the most commonly displayed elasmobranchs in public aquaria. This article expands on the growing body of information regarding veterinary care in elasmobranchs and provides clinicians and researchers with another diagnostic modality to utilize in screening for health/disease.

Tissue and plasma enzyme activities and chemical analytes in Golden Trevally from a public aquarium.

OBJECTIVE: Veterinary care of aquatic species, particularly fish, is limited by a lack of knowledge regarding their unique physiology. Tissue enzyme activities measured in plasma are used for assessing function and potential damage to specific organs and tracking disease progression in live animals. The objective of this study was to identify tissue(s) of origin and plasma concentrations for specific enzymes in healthy Golden Trevally Gnathanodon speciosus. We hypothesized that enzymes would exhibit tissue-specific tropisms, with higher activities in one or more tissues compared to others. METHODS: Six fish were randomly selected from a public aquarium population to obtain antemortem blood samples. The fish were then euthanized, and tissue samples were collected via gross necropsy. Six enzyme activities and two chemical analytes were examined across samples of plasma and 10 tissues from each fish. RESULT: Enzyme activities exhibited significant organ specificities. Aspartate aminotransferase, lactate dehydrogenase, and creatine kinase levels were highest in skeletal muscle, with variably high levels in gonads. Alkaline phosphatase levels were highest in the kidney, spleen, and liver. Alanine aminotransferase levels had high specificity for the liver. Gamma-glutamyl transferase was only detectable in the kidney and plasma. CONCLUSION: This work establishes baseline tissue enzyme origins for Golden Trevally, which will aid clinicians in diagnostic interpretation of blood chemistries and improve veterinary care for this understudied fish species.

Mapping and analysis of laws influencing built environments for walking and cycling in Australia.

BACKGROUND: Physical inactivity is a significant public health concern, with limited signs of improvement despite a global commitment to achieving the World Health Organization's target of 15% reduction by 2030. A systems approach is required to tackle this issue, involving the creation of environments that are conducive to physical activity. Laws represent an important tool for regulating the built environment for physical activity, are a mechanism for systems change, and have the capacity to reorient the goals and rules of a system. However, they are understudied and potentially underutilised for physical activity. Scientific legal mapping is a first step towards understanding how laws could impact the built environment to facilitate greater population physical activity. METHOD: We conducted a legal assessment of state and territory laws in Australia, to systematically characterise how they address built environment considerations with specific relevance to walking and cycling. An interdisciplinary team of researchers with public health, law and urban planning expertise was formed to complete the multistage process. Key steps included a systematic search of laws using a combination of original legal research, consultation of secondary sources, and review and verification by an urban planning expert; development of a coding scheme; and completion of coding and quality control procedures. RESULTS: Most jurisdictions in Australia do not currently embed objectives in primary legislation that would promote physical activity and support an integrated approach to land use and transport planning that encourages active and sustainable lifestyles. Only two jurisdictions addressed the large majority of evidence-based standards that promote active living. Of the standards addressed in law, few fully met evidence-based recommendations. While most jurisdictions legislated responsibility for enforcement of planning law, few legislated obligations for monitoring implementation. CONCLUSION: Increasing physical activity is a systems issue, requiring actions across multiple sectors. An in-depth examination of the legal environment is an important step towards understanding and influencing the existing physical activity system, why it may not be generating desired outcomes, and potential opportunities for improvement. Our findings reveal opportunities where laws could be strengthened to promote more active environments. Updating this dataset periodically will generate longitudinal data that could be used to evaluate the impact of these laws on the built environment and physical activity behaviours.

Bayesian Decision Analysis: An Underutilized Tool in Veterinary Medicine.

Bayesian inference and decision analysis can be used to identify the most probable differential diagnosis and use those probabilities to identify the best choice of diagnostic or treatment among several alternatives. In this retrospective case analysis, we surveyed three experts on the prior probability of several differential diagnoses, given the signalment and history of a ferret presenting for lethargy and anorexia, and the conditional probability of different clinical findings (physical, bloodwork, imaging, etc.), given a diagnosis. Using these data and utility estimates provided by other clinicians, we constructed a decision tree to retrospectively identify the optimal treatment choice between exploratory laparotomy and medical management. We identified medical management as the optimal choice, in contrast to the original clinical team which performed an exploratory laparotomy. We discuss the potential cognitive biases of the original clinical team. We also discuss the strengths, e.g., shared decision making, and limitations of a Bayesian decision analysis in the veterinary clinic. Bayesian decision analysis can be a useful tool for retrospective case analysis and prospective decision making, especially for deciding on invasive interventions or end-of-life care. The dissimilarity of expert-derived probability estimates makes Bayesian decision analysis somewhat challenging to apply, particularly in wide-ranging specialties like zoological medicine.

Sex, drugs and rock iguanas: testicular dynamics and plasma testosterone concentrations could predict optimal semen collection times in Cyclura.

Iguanas are the most endangered family of reptiles, with 77% categorised as threatened or near threatened. Further, Cyclura is the most endangered reptile genus, with all 12 species considered threatened. Therefore, it is vital that we develop assisted reproductive technologies for Cyclura spp. to enhance their conservation efforts. The goals of this study were to collect semen, and to measure testicle size and testosterone concentrations in Grand Cayman rock iguana hybrids (Cyclura lewisi ×nubila (CLN)) and rhinoceros rock iguanas (Cyclura cornuta (CC)). A prospective longitudinal study was performed in 9.0 CLN and 9.0 CC during their reproductive season in southern Florida (February-July). Serial testicle ultrasound measurements and plasma testosterone concentrations were collected monthly. Testicle measurements (length (L), width (W), height (H)) were collected and testicle volume (V ) was estimated using the equation V =0.52(LW 2 ). There were significant differences in testicle L, W, H and V for both species. Testicle size peaked for CLN and CC in April and May respectively. Plasma testosterone concentrations increased from baseline during February, March and April in CLN and in March, April and May in CC. Ultrasound testicle measurements could be used to predict when to collect semen in these seasonally monocyclic iguanas.

Reptile assisted reproductive technologies: can ART help conserve 300 million years of evolution by preserving extant reptile biodiversity?

Biodiversity loss is the greatest environmental problem threatening ecosystem, animal, and human health. Anthropogenic induced changes to climate, habitat, disease, species distributions, poaching, and unsustainable trade have accelerated extinction rates in all vertebrates, including reptiles. Preventing reptile extinctions will require humans to acknowledge these losses and develop ex situ and in situ plans to preserve them. Assisted reproductive technologies (ART) are management tools used to protect numerous vertebrate taxa; however, progress in developing ART for reptiles has lagged. Creating functional and sustainable reptile ART will strengthen our conservation capacity by capturing genetic material from select individuals to overcome natural or manmade boundaries. Utilising short-term gamete storage and genome resource banking, in conjunction with timed artificial insemination (AI) or ex ovo incubation, could lead to profound advances in reptile conservation, mitigating the loss of reptile biodiversity. In this article, we review ART reptile research completed since the 1970s. Topics include AI, hormonal control of reproduction, gamete collection, gamete storage, and genome resource banking. Additionally, we review the potential application of advanced reproductive methodologies, including in vitro /ex ovo fertilisation, intracytoplasmic sperm injection, cloning (somatic cell nuclear transfer), and genetic editing.

Plasma and tissue enzyme activities of banded water snakes (Nerodia fasciata) and diamondback water snakes (Nerodia rhombifer).

OBJECTIVE: To measure plasma and tissue activities of alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase (AST), creatine kinase, and γ-glutamyltransferase in 2 snake species. ANIMALS: 6 banded water snakes (Nerodia fasciata) and 6 diamondback water snakes (Nerodia rhombifer). PROCEDURES: Blood was collected via the ventral tail vein to measure plasma enzyme activities. Animals were then euthanized, and samples of 9 tissues were collected from each snake: skeletal muscle, cardiac muscle, liver, spleen, lung, kidney, testicle, pancreas, and gallbladder. Tissues were frozen for 30 days, then homogenized and processed. Supernatants were collected and analyzed within 24 hours of processing. A linear mixed model was used to determine differences in enzyme activity between tissues and species and assess interactions between tissues and species. RESULTS: Activities of all enzymes were found to differ significantly among tissues. There were also significant differences between species for all enzyme activities, except AST activity. The kidney had the highest alanine aminotransferase and γ-glutamyltransferase activities. Alkaline phosphatase activity was significantly highest in liver and kidney tissues than in other tissue. Creatine kinase activity was highest in skeletal muscle, followed by cardiac muscle and kidney. AST activity was present in all tissues evaluated, but was highest in liver, kidney, and cardiac muscle in both species. CLINICAL RELEVANCE: Results reinforced the importance of characterizing the origin of tissue enzymes in reptiles to improve our understanding of biochemistry results and highlighted the differences that can exist in tissue enzyme activities between closely related species.

Determining the Effects of Serial Injections of Pregnant Mare Serum Gonadotropin on Plasma Testosterone Concentrations, Testicular Dynamics, and Semen Production in Leopard Geckos (Eublepharis macularius).

Reptiles are highly susceptible to anthropogenic activities as a result of their narrow geographical ranges and habitat specialization, making them a conservation concern. Geckos represent one of the mega-diverse reptile lineages under pressure; however, limited assisted reproductive technologies currently exist for these animals. Exogenous pregnant mare serum gonadotropin (PMSG) has been found to exhibit follicle stimulating hormone-like action and has been routinely used to alter reproductive hormones of vertebrates in assisted reproductive protocols. The purpose of this study was to determine the effects of serial injections of 20 IU and 50 IU PMSG on circulating testosterone concentrations, testicular dynamics, and semen production in a model species of gecko. Twenty-four captive-bred, adult, male leopard geckos (Eublepharis macularius) were divided into three treatment groups and administered a once-weekly injection of either PMSG or saline for a total of nine weeks. Ultrasonographic testicular measurements, electrostimulation for semen collection, and venipuncture were performed on days 0, 21, 42, and 63. Right unilateral orchidectomies and epididymectomies were performed in all animals on day 63; tissues were submitted for histopathology. PMSG treated geckos had significantly higher testicular volumes and weights, spermatozoa motility, and spermatozoa concentrations compared with controls. However, there were no significant differences in testosterone concentrations by treatment or time. Under the conditions outlined, PMSG is effective at stimulating spermatogenesis and increasing testicular size, but not effective at increasing testosterone concentrations in the leopard gecko between October-December in the Northern hemisphere.

Serum concentrations of canine pancreatic lipase immunoreactivity and C-reactive protein for monitoring disease progression in dogs with acute pancreatitis.

BACKGROUND: Reliable biomarkers for monitoring disease progression and management in dogs with acute pancreatitis have not been described. OBJECTIVE: To determine if serum concentrations of canine pancreatic lipase immunoreactivity (cPLI) and C-reactive protein (CRP) can be used as biomarkers for disease progression in hospitalized dogs with acute pancreatitis. ANIMALS: Thirteen hospitalized dogs with acute pancreatitis diagnosed based on clinical signs, serum cPLI concentrations, and imaging findings were enrolled. METHODS: Serum cPLI and CRP concentrations were determined before and then daily during hospital management and 1 week after hospital discharge. Modified canine activity index (MCAI) and canine acute pancreatitis clinical severity index (CAPCSI) scores were calculated daily for each patient while hospitalized. RESULTS: The MCAI scores (P = .03) but not CAPCSI scores (P = .31) were significantly different between dogs that survived to discharge (n = 11) and those that did not (n = 2). Serum cPLI concentration was positively correlated with MCAI (rho = 0.42; P = .01). Serum CRP concentration also was positively correlated with the MCAI (rho = 0.42, P = .01). CONCLUSIONS: Serum cPLI and possibly CRP could be used as objective biomarkers for clinical changes in hospitalized dogs with acute pancreatitis. Additional studies involving larger numbers of dogs would be warranted to evaluate the broader impact of these findings.

Enhancement of Synchronization between Physiological Signals during Exercise: A Preliminary Investigation.

During running, interactions were considered between three physiological oscillators - the heart, breaths, and steps. During intense exercise, the oscillations of all three systems are close to regular, producing good conditions to observe and characterise synchronization. The origin, as well as any physiological significance, of synchronization between these systems during running is not fully accepted or understood. Furthermore, the impact on synchronization of controlling both breathing and step rate has not been previously reported in detail. This study aims to measure cardiolocomotor, cardiorespiratory and respiratory- locomotor synchronization during different running protocols. Breathing was controlled by taking a fixed number of steps per breath (ratios of 5:1 and 3:1). Step rate was then guided at rates close to active heart rate, to instigate 1:1 phase-locking. Instantaneous phase difference quantified synchronization episodes. We have successfully observed all three forms of synchronization during all running protocols. Furthermore, coupling between heartbeats and steps was more pronounced when step rate was guided, and both cardiorespiratory and respiratory-locomotor coupling were extended when breathing rate was fixed to steps. These are exciting initial results from a novel experimental design, highlighting the complex interconnection that exists between these three systems during running, and the conditions to best observe the phenomena.

Longitudinal and Cross-Sectional Sampling of Serpentovirus (Nidovirus) Infection in Captive Snakes Reveals High Prevalence, Persistent Infection, and Increased Mortality in Pythons and Divergent Serpentovirus Infection in Boas and Colubrids.

The aim of this study of serpentovirus infection in captive snakes was to assess the susceptibility of different types of snakes to infection and disease, to survey viral genetic diversity, and to evaluate management practices that may limit infection and disease. Antemortem oral swabs were collected from 639 snakes from 12 US collections, including 62 species, 28 genera, and 6 families: Pythonidae (N = 414 snakes; pythons were overrepresented in the sample population), Boidae (79), Colubridae (116), Lamprophiidae (4), Elapidae (12), and Viperidae (14). Infection was more common in pythons (38%; 95% CI: 33.1-42.4%), and in boas (10%; 95% CI: 5.2-18.7%) than in colubrids (0.9%, 95% CI: <0.01-4.7%); infection was not detected in other snake families (lamprophiids 0/4, 95% CI: 0-49%; elapids 0/12, 95% CI: 0-24.2%; and vipers 0/14, 95% CI: 0-21.5%), but more of these snakes need to be tested to confirm these findings. Clinical signs of respiratory disease were common in infected pythons (85 of 144). Respiratory signs were only observed in 1 of 8 infected boas and were absent in the single infected colubrid. Divergent serpentoviruses were detected in pythons, boas, and colubrids, suggesting that different serpentoviruses might vary in their ability to infect snakes of different families. Older snakes were more likely to be infected than younger snakes (p-value < 0.001) but males and females were equally likely to be infected (female prevalence: 23.4%, 95% CI 18.7-28.9%; male prevalence: 23.5%, 95% CI 18-30.1%; p-value = 0.144). Neither age (p-value = 0.32) nor sex (p-value = 0.06) was statistically associated with disease severity. Longitudinal sampling of pythons in a single collection over 28 months revealed serpentovirus infection is persistent, and viral clearance was not observed. In this collection, infection was associated with significantly increased rates of mortality (p-value = 0.001) with death of 75% of infected pythons and no uninfected pythons over this period. Offspring of infected parents were followed: vertical transmission either does not occur or occurs with a much lower efficiency than horizontal transmission. Overall, these findings confirm that serpentoviruses pose a significant threat to the health of captive python populations and can cause infection in boa and colubrid species.

COMPARISON OF SURFACE, ESOPHAGEAL, AND CLOACAL TEMPERATURES IN DIFFERENT REPTILE SPECIES.

The objective of this study was to compare surface, esophageal, and cloacal temperatures in awake iguanas, chameleons, and snakes at two different ambient temperatures and in alligators at one ambient temperature. Surface, esophageal, and cloacal temperatures were measured in all animals twice, with exception of the alligators, where temperatures were taken once. The first set of temperature readings was done at lower environmental temperature. An analysis of variance (ANOVA) with a mixed-effect model was used to analyze the temperature difference between esophageal and cloacal temperature against each other, and against surface temperature. Significance was set at P < 0.05. In all animals, surface, esophageal, and cloacal temperatures increased significantly (P < 0.0001) with increased ambient temperature. Esophageal and cloacal temperature were not significantly different from each other in iguanas and chameleons at lower environmental temperature or in snakes and chameleons at high ambient temperature. In snakes, esophageal temperature 26.1 ± 1.6°C was significantly higher than cloacal temperature 25.2 ± 0.9°C (P = 0.0016) at lower ambient temperature. In alligators no difference between esophageal and cloacal temperature was observed at the given ambient temperature. Surface temperature was significantly lower than esophageal and cloacal temperature in all species investigated, except iguanas at lower ambient temperature. The results of this study suggest that in healthy awake iguanas and chameleons at any ambient temperature and in snakes at high ambient temperature, cloacal temperatures are reflective of esophageal temperature in the species evaluated. In alligators, rectal temperature reflected esophageal temperature at the given ambient temperature. Surface temperature in contrast was underestimating esophageal temperature in all species investigated.

Control of heart rate through guided high-rate breathing.

Understanding the complex dynamics of cardio-respiratory coupling sheds light on the underlying mechanisms governing the communication between these two physiological systems. Previous research has predominantly considered the coupling at respiratory rates slower than the heart rate and shown that respiratory oscillations lead to modulation and/or synchronization of the heart rate. Whereas the mechanisms of cardio-respiratory communication are still under discussion, peripheral nervous regulation is considered to be the predominant factor. This work offers a novel experimental design and applies the concept of instantaneous phase to detect cardio-respiratory entrainment at elevated respiration rates, close to the resting heart rate. If such 1:1 entrainment exists, it would suggest direct neuronal communication between the respiration and heart centres in the brain. We have observed 1:1 entrainment in all volunteers, with consistently longer synchronization episodes seen in physically fitter people, and demonstrated that cardio-respiratory synchronization at both low and high respiration rates is associated with a common underlying communication mechanism.

DETERMINING THE SAFETY OF REPEATED ELECTROEJACULATIONS IN VEILED CHAMELEONS CHAMAELEO CALYPTRATUS.

Investigation into antemortem semen collection methods in reptiles is required to counteract anthropogenic induced reptile biodiversity loss and to further develop assisted reproductive technologies in reptiles. The purpose of this study was to evaluate whether repeated electroejaculation under anesthesia could be done safely in the veiled chameleon (Chamaeleo calyptratus). Electroejaculation under anesthesia (alfaxalone 15 mg/kg intravenously) was performed once weekly over a 4-wk period in 12 Chamaeleo calyptratus. External vent appearance and cloacoscopy was performed prior to and after electroejaculation to assess the effect of the electroejaculation on the external and internal anatomy. Hematological and chemistry values were evaluated prior to the study and afterwards. Semen collection was successful in 50% of the electroejaculation events. Cloacoscopy images scores were significantly higher between the pre- and postelectroejaculation events for each week. No significant difference was observed between study week 1 prior to electroejaculation and study week 4 after electroejaculation in vent external morphology (P = 0.157), and internal cloacal scoring (P = 0.058). A significant increase in the white blood cell counts (P = 0.015), absolute heterophil counts (P = 0.02), absolute monocyte counts (P = 0.003), and albumin (P = 0.038) was observed between the pre- and postejaculation sampling periods. Aspartate aminotransferase (P = 0.001) and potassium (P = 0.036) decreased significantly between the pre- and postsampling periods. Vent image scores were significantly higher (P = 0.046) between the pre- and postsampling images collected during week 1; however, there were no significant differences noted between pre- and postsample images for weeks 2 (P= 0.063), 3(P= 0.083), or 4 (P= 0.083). Serial electroejaculation procedures under alfaxalone anesthesia can be performed safely in veiled chameleons. Although changes were observed in the complete blood count and biochemistry results, these changes were determined to not be clinically significant. The results of this study demonstrate that antemortem assisted reproductive techniques such as electroejaculation can be safely used repeatedly.

Physical fitness contributes to cardio-respiratory synchronization.

Cardio-respiratory synchronization is a phenomenon of particular interest- especially at a 1:1 ratio- and may give greater insight into the underlying mechanisms of cardio-respiratory communication. Synchronization of this ratio is hypothesised to occur when breathing rate exceeds heart rate, which is the premise of this research. A novel experimental design focused on guiding elevated respiration to induce the entrainment of heart rate, and produce an equivalent rise in value. Application of instantaneous phase for identification and analysis of synchronization allowed for a reliable method of measuring the interaction between these stochastic processes. We have identified 1:1 phase synchronization in all volunteers measured. Longer synchronization episodes were observed reliably in athletic individuals, corroborating previous research for spontaneous breathing. This observation suggests that cardio-respiratory synchronization at all respiration rates is associated with a common underlying communication mechanism. Furthermore, it presents cardio-respiratory synchronization as a potential future measurement of fitness and autonomic health.

Pain and Its Control in Reptiles.

Reptiles have the anatomic and physiologic structures needed to detect and perceive pain. Reptiles are capable of demonstrating painful behaviors. Most of the available literature indicates pure µ-opioid receptor agonists are best to provide analgesia in reptiles. Multimodal analgesia should be practiced with every reptile patient when pain is anticipated. Further research is needed using different pain models to evaluate analgesic efficacy across reptile orders.

Evidence-Based Advances in Reptile Medicine.

Evidence-based medicine allows veterinarians to practice high-quality medicine, because the basis for all decision making is quantitative, objective, and reproducible. Case reports and case series are limited in their scope and application. Cross-sectional studies, likewise, cannot provide answers to specific variable testing with a temporal application. It is essential for the reptile specialty to expand into case-control studies, cohort studies, and experimental/intervention studies. Unfortunately, much of the reptile literature remains limited to descriptive studies. This article reviews current evidence-based topics in reptile medicine and shares how everyone practicing in the field can contribute to improving this specialty.

Reproductive Medicine in Freshwater Turtles and Land Tortoises.

Chelonian reproductive medicine is an extremely important facet to ensuring captive populations for the pet trade and conservation efforts around the globe. This article covers basic chelonian reproductive anatomy and physiology, natural history, behavior, and sexing chelonians, in addition to discussing reproductive disorders that are commonly seen by veterinarians. Reproductive disorders covered include infertility, dystocia, follicular stasis, egg yolk coelomitis, phallus prolapse, and reproductive neoplasia. It is hoped that this information will allow clinicians to recognize, understand, and successfully treat reproductive disorders in chelonians, thus providing the best available care for our chelonian patients.

Dental onlay bridge-like prosthesis in three koalas (Phascolarctos cinereus): the use of Premise trimodal composite to prevent interproximal Eucalyptus spp. retention and infection.

Three koalas (Phascolarctos cinereus) presented with moderate to severe interproximal space accumulation with Eucalyptus spp. at the San Diego Zoo. Premise trimodal composite was used to create dental onlay bridge-like prostheses to eliminate open, enlarged interproximal spaces. The prostheses prevented further leaf material accumulation within the interproximal spaces and consequently reduced periodontal disease. Aesthetically, the prosthesis replicates normal tooth coloration and appearance and wears at a similar rate to surrounding teeth. Prosthetic repair or replacement may be required, so periodic examination every 3-6 mo is recommended.