Intraoral disease, including macropod progressive periodontal disease, is one of the leading causes of morbidity and mortality for wallabies under human care. Clinical signs associated with intraoral disease vary, and diagnostic findings can be difficult to interpret without intraoral radiographs or advanced imaging; therefore, this disease process can be challenging to detect in its early stages. Previous studies have investigated the effects of intraoral disease on the normal oral microbiome of various domestic species. Results from these studies demonstrate specific changes to the oral microbiome that have the potential to be used as an early indicator of intraoral disease. The purpose of this study was to evaluate the oral microbiome of 12 Bennett's wallabies (Notamacropus rufogriseus) and 3 yellow-footed rock wallabies (Petrogale xanthopus), using next-generation sequencing, to determine if intraoral disease influences the oral microbiome, as demonstrated in other species. The study identified a total of 295 bacterial species and 388 fungal species from the oral cavity of 15 wallabies. Although not statistically significant, the results of the study suggest an increase in the number of anaerobic bacterial species in sites of disease, including Actinomyces bowdenii, a species from the family Propionibacteriaceae, Peptostreptococcus canis, Fretibacterium sp., and Synergistes jonesii. It also revealed a decrease in microbial diversity in animals with active intraoral disease compared with animals without active disease, as well as at the site of disease compared with the control site. Results from this study support the findings of similar studies assessing the oral microbiome of macropods. Additional studies are warranted to better understand the normal oral microbiome of Bennett's and yellow-footed rock wallabies and the dynamic changes in the microbiome that occur in animals with intraoral disease.

Cortisol, and other glucocorticoids, are routinely used as markers of physiological stress in wildlife. Typically, stress activates the hypothalamic–pituitary–adrenal (HPA) axis, with adrenocorticotropic hormone (ACTH) signaling the adrenal glands to release cortisol. Nevertheless, recent anecdotes in captive Coquerel's sifakas (Propithecus coquereli), strepsirrhine primates that are difficult to maintain under human care, may challenge the assumption that physiological stress universally increases circulating cortisol. Here, the authors ask if low circulating cortisol and minimal response to adrenal stimulation might be hallmarks of outwardly healthy sifakas in captivity. Comparative ACTH stimulation or control tests were performed in 10 Coquerel's sifakas and six ring-tailed lemurs (Lemur catta) at the Duke Lemur Center (DLC). At baseline, sifakas had average cortisol concentrations of just 0.67 µg/dl, whereas those of ring-tailed lemurs averaged 12.53 µg/dl. Stressful pre-experiment procedures, including kenneling and handling, activated the HPA axis in ring-tailed lemurs, masking further cortisol release from ACTH administration; however, neither these procedures nor exogenous ACTH raised cortisol concentrations in sifakas. Additionally, cortisol in dozens of serum samples from DLC sifakas banked over 17 yr was assayed. Across samples, cortisol concentrations averaged just 0.49 µg/dl and did not vary by animal sex, age, or housing condition. Comparable samples from two individual sifakas in sepsis at the end of life (4.28 and 21.88 µg/dl) indicate that the assay does capture meaningful variation in cortisol in captive sifakas, although robust biological validation is needed. Currently there is a lack of comparative data from wild Coquerel's sifakas that might determine if these unusual endocrine patterns are characteristic of the species or a function of captivity. If the latter, chronic stress in captivity could lead to a downregulated HPA axis, with persistent hypocortisolism perhaps contributing to the Coquerel's sifaka's susceptibility to infection under human management.

American alligators (Alligator mississippiensis) are an important apex predator of semiaquatic habitats of the southern United States. Commercial alligator farming has grown in the last several decades, leading to a need to understand the health conditions that affect this species to ensure appropriate management and welfare. The aims of this study were 1) to establish and describe normative data including results of common ophthalmic diagnostic tests and conjunctival flora, 2) document ocular pathology in this population, and 3) assess the effect of topical rocuronium bromide and 10% phenylephrine for facilitating pharmacologic mydriasis. A total of 165 juvenile American alligators were evaluated in this study. Assessment included palpebral fissure length (PFL), intraocular pressure (IOP), strip meniscometry (SM), central corneal thickness (CCT), anterior segment examination, and bacterial and fungal culture sampling of the conjunctiva. Topical rocuronium bromide (RB) and 10% phenylephrine (PE) were applied to the right eye (OD) of eight individuals, and pupil diameter (PD) of both eyes measured at regular time intervals. Mean (±standard deviation [SD]) PFL was 10.55 ± 1.47 mm, IOP was 8.16 ± 1.48 mmHg, CCT was 150.06 ± 8.25 µm, and SM was 3.42 ± 2.07 mm/5 s. Culture results stress the importance of proper handling protocols in crocodilians given the high number of opportunistic pathogens isolated from the conjunctiva, as well as the first report of isolation of Lactococcus garvieae in this species. Acquired ophthalmic lesions, likely traumatic, were recorded and no congenital anomalies were observed. Topical administration of RB and PE resulted in a significant increase in nonilluminated pupil diameter (PD) starting at 20 min, and maximum dilation was achieved at 90 min. Fundic examination was achievable, and no adverse systemic effects were noted. This study contributes to a growing body of knowledge regarding ocular health of American alligators.

Etorphine based immobilization protocols are reported to be effective in pronghorn; however, information on cardiorespiratory effects is limited. The objective of this study was to evaluate the efficacy and cardiopulmonary effects of etorphine, medetomidine, midazolam, and azaperone for immobilization in captive pronghorn. Additionally, the effects of endotracheal intubation and manual ventilation on cardiopulmonary variables were assessed. A combination of 5 mg etorphine, 10 mg medetomidine, 2.5 mg midazolam, and 5 mg azaperone was administered by hand or via dart to 10 pronghorn. Five pronghorn were endotracheally intubated once recumbent and manually ventilated. Oxygen at a flow of 6 L/min was supplemented to all animals. Induction and recovery times were recorded, and during recumbency vital parameters and arterial blood samples were collected. Time to lateral recumbency was 3.8 ± 1.25 min. Marked hypoxemia and hypercapnia was observed in both spontaneously breathing and manually ventilated pronghorn. Hypercapnia improved significantly in manually ventilated pronghorn compared to spontaneously breathing animals. All pronghorn recovered rapidly after reversal with 150 mg naltrexone and 30 mg atipamezole. Administration of etorphine, medetomidine, midazolam, and azaperone resulted in excellent chemical immobilization in pronghorn. Significant hypoxemia and hypercapnia occurred and oxygen supplementation, endotracheal intubation, and manual ventilation is recommended.

Bone lengths of paired digits of front and hind limbs from 12 captive European bison (Bison bonasus) of different ages (from nine to 175 months) and sexes were measured on digital radiographs in palmarodorsal (PaD) and dorsoplantar (DPl) projections of each limb. All bone lengths were measured, and lateral/medial ratios calculated. The bone measurements included length of the canon bone condyle (LCBC), length of the first, second, and third phalanges (LP1, LP2, LP3), and overall digit length (OL). Furthermore, radiographic abnormalities such as new bone formation (NBF), soft tissue mineralization (SFT), osteolysis (OS), widened vascular channels (WVC), and soft tissue swelling (STS) were recorded using PaD, DPl, and oblique projections. NBF and SFT received a single combined grade as without radiographic changes (0), mild (one to 10 changes = 1), moderate (11 to 20 changes = 2), and severe (>20 changes = 3). OS, WVC, and STS were graded as 0 = absent and 1 = present. There were no significant differences (P > 0.1) of lateral to medial ratios for LCBC, LP1, LP2, and OL in front limbs as compared with hind limbs. Only LP3 was significantly longer (P = 0.004) in the lateral digit of the hind limbs as compared with the front limbs. For both the front and the hind limbs, the lateral LCBC, LP1, LP2, LP3 and OL were significantly longer than the respective measurements of the medial bones (P < 0.05), except for LP2 and LP3 of the hind limbs. Length measurement ratios did not vary significantly with age (P > 0.1). The most common radiographic changes were both NBF and SFT, observed in all animals from 39 months of age and older. This study provides baseline data on in vivo radiographic anatomy and evaluation of feet of European bison under field conditions.

Aspergillosis is the most important disease in hunting/racing falcons in the Middle East. Based on clinical observations, the gyrfalcon (Falco rusticolus) is considered to be more susceptible than other species of falcons, whereas it has been hypothesized that their hybrids might be more resistant. This retrospective study examined the endoscopic results of 3,754 captive-bred juvenile falcons of three different species and their hybrids, admitted to Dubai Falcon Hospital in their first year in the UAE over a 14-year period. A control cohort of confirmed genetic origin from Dubai Falcon Center was also examined. Aspergillosis was diagnosed in 887 falcons. The overall prevalence, regardless of species, was 24%. Gyrfalcons (F. rusticolus) had a prevalence of 27%, peregrine falcons (Falco peregrinus) of 18%, and saker falcons (Falco cherrug) of 26%. There was no significant difference in the prevalence of aspergillosis between the total hybrid population and the total purebred population. Among purebreds, there was a statistically significant difference only between gyrfalcon and peregrine falcon, with the gyrfalcon being more sensitive. Additionally, the gyrfalcon had a statistically higher prevalence of aspergillosis than the total population of gyrfalcon hybrids. The most resistant hybrid proved to be the gyrfalcon × peregrine (prevalence 20%). This was also verified in the Dubai Falcon Center cohort. In assessment of two main gyrfalcon hybrids in accordance with their parental ancestors, the gyrfalcon–peregrine hybrid proved to be more resistant than the gyrfalcon ancestry, but not the peregrine ancestry. The gyrfalcon–saker presented numerically higher prevalence (30%) than both parents (gyrfalcon, saker falcon), showing outbreeding depression. There was no statistically significant difference between captive-bred sakers (prevalence 24%) and legally harvested wild-caught sakers from Mongolia (prevalence 26%). This work partially confirmed the clinical hypothesis of gyrfalcon sensitivity and hybrid superiority regarding aspergillosis prevalence, only in relation to the peregrine falcon and the gyrfalcon–peregrine hybrid.

The aye-aye (Daubentonia madagascariensis) is an unusual lemur with a small population in human care. Cardiac pathologies, but not normal size parameters, have been reported in this species. This study aimed to determine whether radiographic cardiac scaling systems commonly used to evaluate heart size in domestic mammals have potential clinical application in aye-ayes. Selected cardiac silhouette, vertebral, and intrathoracic skeletal dimensions were measured retrospectively on paired sets of orthogonal thoracic radiographs collected during health examinations of aye-ayes maintained at three British zoos. Measurements from 21 healthy aye-ayes (10 males, 11 females) of varying ages were used to calculate reference intervals (RI) with 90% confidence intervals for vertebral heart scale in both right lateral (VHS-RLat) and ventrodorsal (VHS-VD) projections, a modified VHS (VHS-Mod), thoracic inlet heart size (TIHS), and cardiothoracic ratio (CTR). VHS-VD (9.49 ± 0.29) was slightly higher than VHS-RLat (9.32 ± 0.33; P = 0.08) and had the lowest coefficient of variation of the scaling indices; TIHS was 4.89 ± 0.36, VHS-Mod was 11.07 ± 0.49, and CTR was 0.53 ± 0.05. Thoracic depth-to-width ratio of aye-ayes ranged between 0.75 and 0.91, equivalent to an intermediate thoracic morphology in dogs. No scaling indices differed significantly by sex, age group, or thoracic morphology; however, VHS-Mod and CTR were significantly correlated with bodyweight (P = 0.0022 and P = 0.041, respectively) and CTR with age (P = 0.02). Summed cardiac dimensions demonstrated a near-linear relationship with bodyweight and T4 vertebral length (both P < 0.05), but not thoracic inlet length (P = 0.12). Analysis of measurements by using serial radiographs from hand-reared animals indicated potential utility of RI in aye-ayes >0.4 yr. Overall, results suggest VHS-VD and VHS-RLat are preferred cardiac scaling indices in aye-ayes. These data will aid zoo clinicians in the evaluation of cardiac size and identification of cardiomegaly in this endangered primate.

Florida manatees (Trichechus manatus latirostris) continue to experience pressure from various stressors that frequently result in the need for rescue and veterinary assistance. Interestingly, a subset of rescued manatees in critical condition exhibits profound hypoglycemia. The goals of this study were to enhance our understanding of this important aspect of manatee care by 1) characterizing the clinical presentation and factors associated with manatees that present with profound hypoglycemia, and 2) assessing agreement across blood glucose testing modalities [glucometer (whole blood), in-house bench-top analyzer (whole blood), a point of care analyzer (whole blood), and a local human hospital laboratory analyzer (serum)]. Twenty-five manatees were admitted to the Jacksonville Zoo and Gardens from 2017 to 2021. Seven manatees were profoundly hypoglycemic on presentation with blood glucose concentrations of < 30 mg/dL. Hypoglycemic manatees were admitted due to cold stress syndrome (n = 3; 1 calf, 2 adults) or emaciation consistent with an unusual mortality event (n = 4; 2 calves, 2 adults). Physical examination findings in hypoglycemic animals included emaciation (n = 7, 100%), lethargy (n = 7, 100%), and intermittent mild muscle fasciculations of the muzzle (n = 3, 42.8%). Hypoglycemia resolved with intense supportive care and monitoring in all affected animals within 32 h of admission. No associations were identified between hypoglycemia on presentation and life-stage, sex, transport distance to JZG's critical care facility, or rehabilitation outcome (death/euthanasia vs. release). Statistical agreement was observed between all blood glucose testing modalities except for the glucometer vs. the human hospital analyzer. Despite the limited sample size, these findings inform on the clinical presentation of severe hypoglycemia, the importance of close blood glucose monitoring after admission, blood glucose testing modalities, and clinical decision-making in Florida manatees admitted to critical care centers.

We describe a mortality event involving at least 44 adult American robins (Turdus migratorius) that were found dead on the morning of February 25, 2023 in a residential backyard in Natchitoches Parish, Louisiana. Five carcasses were submitted for diagnostic evaluation. All five robins were in good nutritional and feather condition with no external indicators of injury or illness. Grossly, kidneys were diffusely pale in all robins and 4/5 also had splenomegaly. Consistent histologic lesions included severe, multifocal to coalescing, renal tubular degeneration and necrosis with intraluminal, birefringent calcium oxalate crystals and calcified concretions. Toxicologic testing revealed a markedly elevated calcium concentration (10,000 parts per million) in a pooled kidney sample. Collectively, these findings support a diagnosis of ethylene glycol toxicosis. Ethylene glycol, an ingredient in antifreeze, is a hazardous toxicant in domestic and wild animals living in residential areas, although confirmed reports in songbirds are scarce. In the present case, the circumstances of ethylene glycol exposure are unknown but most likely anthropogenic in origin. Additionally, splenomegaly prompted molecular testing, which detected Plasmodium unalis in three robins and P. vaughani in one robin. Both Plasmodium spp. can infect a wide range of hosts, and although infections likely were subclinical, their detection raises awareness of their potential pathogenicity in wild birds. This mortality event underscores the need to recognize health risks posed by environmental contaminants and vector-borne pathogens to wildlife, and reinforces that wildlife, especially peridomestic species, can serve as sentinels for risks to domestic animal and human health.

Malaysian fire snails (Platymma tweediei), face threats to their environment, including habitat destruction and the illegal wildlife trade. Captive breeding projects are likely to play a role in the survival of this species; however, mortality in captive populations potentially presents a significant challenge. This paper presents the results of histopathologic examination of tissues from 10 P. tweediei casualties in a captive population at Chester Zoo. In October 2022, a captive breeding program was established with 20 wild-born P. tweediei. All adult founder animals died by July 2023, of which 10 were submitted for necropsy and histopathology of organs. Significant histologic abnormalities were present in all cases, primarily affecting the lung, integument, and heart. Histological analyses indicated a pneumonia-like condition was prevalent in all cases, suggesting potential environmental factors contributed to respiratory infections. A variety of possible etiologic or secondary infectious agents were present in sections including bacteria, fungi, and trematodes. There were some challenges in interpreting the histologic changes, emphasizing the need for more reference material and studies on the normal histologic anatomy of terrestrial gastropods. The findings underline the importance of understanding mortality events in captive populations to improve husbandry and environmental management. Additionally, the study recommends the submission of fresh specimens for necropsy to enhance diagnostic capabilities, such as bacterial culture, and suggests targeted sampling strategies for future research on captive snail species.

Crustaceans are housed in zoos and aquariums and have also gained importance in the private sector and food industry. Shell lesions are common and often attributed to bacterial infections. However, few controlled studies have been performed evaluating antibiotics in crustaceans. This study assessed the pharmacokinetics of a single dose of ceftazidime (22 mg/kg) given by IM or IV injection in wild-caught signal crayfish (Pacifastacus leniusculus). Pharmacokinetic parameters were calculated by noncompartmental analysis of sparse data. Maximum ceftazidime hemolymph concentration following IM administration was 124.6 ± 14.7 µg/mL and Tmax was 5 min, with 80% bioavailability. Following IV administration, the extrapolated maximum concentration of ceftazidime, (C [0]), was 581.4 µg/mL. Ceftazidime was last detected at 72 hr and 120 hr post IM and IV administration, respectively. Terminal half-life was 8.03 hr and 10.3 hr after IM and IV administration, respectively. Results suggest that both routes have the capacity to reach a maximum hemolymph concentration quickly in signal crayfish. Moreover, ceftazidime was maintained above a concentration of 4 µg/mL, a published minimal inhibitory concentration for Vibrio spp., for 24 hr for both IM and IV routes. Therefore, ceftazidime may be useful for infections with susceptible Vibrio spp. in signal crayfish.

Serial health assessment of a managed population of American horseshoe crabs (HSC; Limulus polyphemus) was performed. Twenty HSC were examined once a month for 7 mon; this included a physical exam with a standardized scoring sheet, HR, morphometrics, and hemolymph evaluation with hemocyte count, copper concentration, and biochemistry panel. The HSC in this population had varying levels of external lesions at enrollment. All HSC were clinically and behaviorally stable over the study period, with no apparent differences in evaluated parameters in relation to degree of external lesions. Although the standardized scoring sheet was found to be helpful to complete the evaluation, the qualitative criteria potentially masks clinically important gradations in some parameters. HR ranged from 4 to 60 bpm, with high intra- and interindividual variability. Increased prosomal widths (PW) were found to be correlated with lower HR. Plots of weight (W) in grams divided by PW in centimeters are roughly linear, and W:PW shows promise as a method of body condition evaluation in a hard-shelled animal. Serial collection of ∼2 ml of hemolymph led to no appreciable clinical decline in any animal. Total protein levels were stable and higher than previously reported for HSC in managed care. Glucose values were stable throughout the study period, which is interpreted as reflecting adequate nutritional intake in the study animals. Further studies are needed to determine the clinical utility of standardized vertebrate biochemistry panels in invertebrate species.

The establishment of prognostic indicators in wildlife patients aids clinical decision-making and resource allocation. Hematological and plasma biochemical parameters were evaluated as potential prognostic indicators in wild Temminck's pangolins (Smutsia temminckii) rescued from the illegal wildlife trade. In this prospective cohort study, EDTA and lithium heparin blood samples were collected from the ventral coccygeal vein in 41 pangolins within 48 h of confiscation and before veterinary intervention. Receiving operator characteristic curve analysis was performed to assess each parameter as a prognostic indicator for release outcome and, where known, for 28 d survival postadmission. RBC counts, hemoglobin concentration, and Hct were significantly lower in female than in male pangolins. On intake, pangolins that later failed to be released had significantly lower mean corpuscular hemoglobin concentration (MCHC), higher blood urea nitrogen (BUN), and higher creatinine (Crea) values than individuals that were released. Individuals with lower MCHC or higher Crea values were also less likely to achieve 28-d survival. No pangolin with MCHC < 30.2 g/dl, BUN > 84 mg/dl, or Crea > 0.8 mg/dl was successfully rehabilitated. No other hematological or biochemical parameter, including plasma cortisol, total protein, lactate, lactate dehydrogenase, and glucose, showed significant prognostic value. This study suggests that MCHC, BUN, and Crea measured on intake are useful prognostic indicators for rehabilitation success and MCHC and Crea for short-term survival in Temminck's pangolins.

Bearded dragons (Pogona vitticeps) are a common reptile species kept under human care and suffer from a wide range of diseases for which plasma biochemistry is used as a first-line diagnostic test. There is limited information available regarding tissue enzyme activities and origin that could assist in interpreting the bearded dragon plasma biochemistry enzymology profile. The aim of this study was to characterize the tissue activities of seven enzymes routinely used in the reptile biochemistry panel: alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), glutamate dehydrogenase (GLDH), lactate dehydrogenase (LDH), and creatine kinase (CK) in 12 adult inland bearded dragons in 13 tissues, plasma, and red blood cells. CK activity was highest in skeletal muscle followed by cardiac muscle; ALT and AST were distributed in several tissues and were relatively non-specific for all organs, additionally hepatic fat accumulation reduced AST hepatic activity on a weight per weight basis. ALP and GGT activities were mostly high in the kidneys; LDH activity was elevated in cardiac muscle and skeletal muscle followed by liver; and GLDH had primarily high enzyme activities in liver. Low red blood cell enzyme activities suggest that hemolysis is unlikely to artifactually increase AST or LDH plasma concentrations. These results provide a stepping stone to improve the interpretation of biochemistry results in bearded dragons, especially as it compares to other reptile species.

Recent unusual mortality events involving skin pathology in bearded (Erignathus barbatus), ringed (Pusa hispida), and spotted seals (Phoca largha) in Alaska highlight the potential sensitivity of ice-associated species to the complex effects of climate change. The regulation of thyroid hormones, cortisol, and vitamin A have been shown to play essential roles in skin health and seasonal molt in some pinnipeds. Unfortunately, the lack of available reference data for healthy Alaskan ice seals has prevented the adequate evaluation of these factors in cases associated with mortality events. To improve understanding of blood analytes that may serve as useful markers of skin health, we compiled diagnostic information for individuals in long-term managed care following short-term rehabilitation. Thyroid hormones (TT4, TT3, and FT4d), cortisol, and vitamin A levels are reported for four ringed seals, four spotted seals, and three bearded seals at the Alaska SeaLife Center in Seward, Alaska, with serial samples obtained when possible and referenced to time of year. For ringed and spotted seals, the thyroid hormones and vitamin A showed a strong seasonal pattern with peak values obtained during the annual molt in spring, whereas cortisol values did not vary predictably between molting and non-molting periods. Trends were similar for individuals across both sex and species. Bearded seals had fewer available data for younger individuals only, but observed analyte values are provided for this understudied species. Collectively, these measurements can be used to support veterinary management of ice seals under human care and to provide initial baselines for skin health monitoring in wild populations and in stranded individuals with known skin lesions or pathology.

Evaluating renal function is essential for managing captive wild animals, particularly threatened species like the Amazonian manatee (Trichechus inunguis) in rehabilitation and prerelease programs. A series of urine diagnostic tests, such as gross appearance, semiquantitative chemical analyses, microscopic review of sediments, and quantitative analyses of urea and creatinine, were performed in 57 free-catch urine samples. On the same occasion, 52 serum samples from the same individuals were analyzed for creatine kinase activity, creatinine, blood urea nitrogen, albumin, sodium, potassium, and chloride concentrations; serum symmetric dimethylarginine (SDMA) was measured for the first time in the species. Females had higher urine creatinine concentration (21.7 ± 11.8 mg/dl) and specific gravity (1.003 ± 0.003 mg/dl) than males (11.9 ± 8.5 mg/dl and 1.001 ± 0.002 mg/dl) (P < 0.01 for both). Males presented higher urine creatinine:urea ratio than females (24.8 ± 29.2 and 20.5 ± 29.2, respectively) (P < 0.05). Urine pH was lower in manatees from the semicaptive area (7.8 ± 0.6) than in manatees under human care (8.5 ± 0.6) (P = 0.02) using the benchtop pH meter but showed no difference between areas in the dipstick reaction (P = 0.71), given its lower sensitivity and narrower range detection. Furthermore, 18 and 75% of urine samples were positive for the presence of blood and/or nitrite, respectively, in the dipstick reaction, possibly because of sample contamination. Significant correlation was observed between serum blood urea nitrogen and urine urea concentrations (P = 0.02), and between serum and urine creatinine concentrations (P = 0.01). Serum SDMA did not differ between sex or between captive and semicaptive individuals. However, it positively correlated with urine (P = 0.02) and serum creatinine (P = 0.01) demonstrating its potential as a bioindicator of kidney function. The renal function of Amazonian manatees can be effectively assessed by urinalysis, especially when combined with serum biochemistry.

Wildlife species are routinely captured for translocation, general health monitoring, and research-based pursuits to guide wildlife management. Mule deer (Odocoileus hemionus) were captured for various research projects and management actions in the Trans-Pecos and Panhandle regions of Texas from 2015 to 2019. The objective of this study was to develop hematologic and biochemical parameters for free-ranging mule deer in Texas and to develop a health monitoring system for current and future mule deer population management. Blood samples were collected from 364 mule deer (male = 81; female = 283) and complete blood counts and serum biochemical profiles were performed by Texas Veterinary Medical Diagnostic Laboratory. A subset of 263 individuals, deemed healthy based on several inclusion criteria, were used to establish normal reference intervals for the species. The deer were also tested for serologic evidence of previous exposure to bluetongue virus (BTV) and/or epizootic hemorrhagic disease virus (EHDV) to further characterize the health status of the population. Several variables associated with deer capture and/or health status, including the use of anesthetic drugs, elevated body temperature, capture location, and sex, affected mean blood values; however, the development of separate reference intervals by class was not warranted because of the lack of any clinically relevant change. Antibodies to BTV and EHDV were identified in 76% (277/364) and 78% (285/364) of the population, respectively, and 71% (258/364) had antibodies to both diseases. This study provides hematologic and biochemical reference intervals based on a subpopulation of apparently healthy free-ranging mule deer that should guide wildlife managers in decision-making for future conservation and restoration objectives.

Flamingos in managed care are vulnerable to inflammatory states, including pododermatitis, trauma, and capture myopathy. Fatty acids are an important component of well-balanced nutrition and crucial to endogenous immune responses associated with these conditions, yet fatty acids have not been assessed in flamingos. This study reported complete whole blood circulating fatty acid profiles in two flamingo species in managed care receiving different diets. Whole blood from Chilean flamingos (Phoenicopterus chilensis) (n=16) and Caribbean flamingos (Phoenicopterus ruber) (n=17) was collected during routine exams and prepared on blood spot cards for complete fatty acid profile analysis in which 24 individual fatty acids, nine fatty acids groups, and four calculated parameters were quantifiable. Non-parametric statistical analysis compared profiles between species, and between sex of Chilean flamingos. The median ratio of omega-6/omega-3 fatty acids was 5.64. Chilean flamingos had significantly (P<0.05) higher percentages of 11 individual fatty acids, total polyunsaturated and highly unsaturated fatty acids, total omega-3 and omega-6 fatty acids, arachidonic acid (AA; 20:4w6)/eicosapentaenoic acid (EPA; 20:5w3) ratio, and total EPA + DHA, whereas Caribbean flamingos had significantly (P<0.05) higher percentages of eight individual fatty acids, and total saturated fatty acids. Male Chilean flamingos had significantly (P<0.05) higher percentages of AA, EPA, and total polyunsaturated fatty acids, whereas females had significantly (P<0.05) higher oleic acid (18:1w9), total monounsaturated fatty acids, and total omega-9 fatty acids. Differences reported are highly attributable to variability in diet, although differences in fatty acid synthesizing pathways and hormonal influences may also play a role. This novel fatty acid data set in healthy flamingos is a valuable reference for complete health evaluations in managed care settings. Further comparisons with controlled diets and inclusion of free-ranging animals may enhance clinical utility.

Anticoagulant choice can have significant effect on complete blood counts of reptiles and has not been reported in bearded dragons (Pogona vitticeps). Whole blood was collected from 14 captive individuals and aliquoted into separate blood tubes containing dipotassium ethylenediaminetetraacetic acid (EDTA) and lithium heparin. Samples were shipped and processed within 24 h. A CBC, including a WBC count using a commercial phloxine method, was performed on blood from both tubes. A WBC estimate, WBC differential, and morphologic review were performed on blood smears made from the anticoagulated blood, as well as on a direct blood smear made from anticoagulant-free blood. Some CBC values were significantly different between the EDTA and lithium heparin samples. Hematologic data generated from direct blood smears were more similar to data from EDTA samples than to data from lithium heparin samples. Additionally, multiple lithium heparin samples had poor phloxine stain uptake and leukocyte clumping, so that many WBC parameters were altered or unreportable. These results support EDTA as an appropriate anticoagulant for bearded dragon hematologic evaluation and suggest it may be superior to heparin for some individuals in generating a WBC count using a commercial phloxine method.

Currently there are few antibacterial dosage regimens established to be safe and effective for sea turtles. Pharmacokinetic evaluation of antibiotics is an essential step in establishing accurate dosage guidelines for a particular species. Metronidazole is an antibiotic that is effective against anaerobic bacteria and some protozoa. For most anaerobic bacteria, the minimum inhibitory concentration (MIC) for metronidazole ranges from 0.25 to 4.0 µg/ml. The MIC values for some Clostridium species are up to 8 µg/ml, and for protozoal agents of trichomoniasis (MIC of 0.05 µg/ml), amebiasis, and giardiasis the MIC ranges from 1 to 50 µg/ml. The objective of this study was to determine the pharmacokinetic parameters after administration of metronidazole to aid in the establishment of species-specific dose guidelines in green (Chelonia mydas), loggerhead (Caretta caretta), and Kemp's ridley (Lepidochelys kempii) sea turtles. After administering metronidazole at a dose of 20 mg/kg orally and IV, the pharmacokinetics were very similar for these three species of sea turtles (n = 6 for each species). For both oral and IV routes of administration, plasma metronidazole concentrations were maintained above 8 µg/ml for approximately 24 h and above 4 µg/ml for approximately 48 h; however, plasma concentrations of 8 µg/ml were reached within 5 min only for the IV route, versus 8 h for the oral route.

Hand-rearing protocols for nondomestic ungulates used for research, zoological parks, and reintroduction to the wild are evaluated on the basis of implementation practicality, gastrointestinal disturbances, survival to weaning, and growth rates compared with those of dam-raised individuals. Although species-specific protocols utilizing milk replacers formulated for nondomestic ungulates have been reported, no such protocols have been published for pronghorn (Antilocapra americana). Five pronghorn fawns were fed Day One 30/40 Black Tail Deer plus Lactobacillus acidophilus probiotics four times per day with Day One Ultra Boost (all products from Fox Valley Animal Nutrition, Inc, Huntley, IL 60142, USA) added at one feeding per day and weighed twice per week for up to the first 16 wk of life. All fawns survived beyond weaning and four out of five fawns experienced a combined total of seven bouts of diarrhea. Based on a linear mixed-effects model, the growth rate of pronghorn fawns was 178 g/d (SE, 14.8; 95% CI, 149–207). The observed growth rate was greater than or similar to that of individuals fed evaporated milk five times per day, a dam-raised singlet, and a singular set of dam-raised twins. Despite small sample sizes, this protocol shows promise as a method for hand-rearing pronghorn at growth rates comparable to those of dam-raised fawns.

Only limited data on concentrations of trace elements in the blood of avian species have been published. This information can play an important role in the conservation of endangered species and their protection from environmental pollutants and can also be clinically relevant in managed individuals. Some elements are essential for the health of the animals in human care, but little is known about expected concentrations for some of these elements. Therefore, 21 elements (silver, arsenic, gold, barium, cadmium, cobalt, chromium, copper, iron, iodine, mercury, magnesium, manganese, molybdenum, nickel, platinum, antimony, selenium, thallium, vanadium, and zinc) were measured by inductively coupled plasma mass spectrometry in lithium-heparinized plasma samples from Humboldt penguins (Spheniscus humboldti) from a single zoological collection in Germany (n = 39). The plasma concentrations of cadmium, nickel, platinum, antimony, and thallium were under the limit of detection in most of the analyzed samples. The results also showed that the females had significantly (P ≤ 0.05) higher concentrations of silver, barium, cobalt, chromium, iron, mercury, magnesium, vanadium, and zinc in their plasma in comparison with males. A correlation between the element plasma concentration and the age of the individuals could not be found. The differences in plasma concentrations of individual element between males and females could be due to hormonal influences on the metabolism. Further studies in different seasons and other age groups are needed in the future to investigate environmental and host effects in more detail and to understand physiological mechanisms responsible for observed differences.

Salmonella spp. are one of the leading causes of illness, and in the last years there is an increasing interest in the role of different wild animals as reservoir of Salmonella enterica, especially multidrug resistant strains. To establish preventive and action strategies, it is essential to monitor bacterial resistance profiles and systematically collect information. This study aims to report Salmonella enterica and their resistance profile isolated from feces of wild felids that receive veterinary cares by the Hospital de Especies Menores y Silvestres, Costa Rica in 2021 and 2022. Overall, 100% (7/7) of Salmonella spp. isolates exhibited resistance against cefazoline, followed by 71% (5/7) to ciprofloxacin, and 43% (3/7) to nitrofurantoin. A single isolate was found to be multidrug resistant against Ampicillin/Sulbactam-Cefazolin-Ceftriaxone-Gentamicin-Ciprofloxacin-Nitrofurantoin. These resistant profiles highlight that Salmonella enterica isolation can represent a threat to public health and wildlife conservation, especially for those organisms expressing resistant phenotypes to drugs commonly used in clinical settings. Fluoroquinolone resistant Salmonella spp. have been called by the World Health Organization a high priority for research. As these organisms are expanding beyond livestock and hospital associated environments, to understand the epidemiology and impact of fluoroquinolone-resistant Salmonella spp. we require a One Health approach.

Penile abnormalities in cheetahs (Acinonyx jubatus) are rare but can present significant challenges to both captive and wild populations. This is the first report of penile abnormalities in cheetahs, and results from the screening of 549 male individuals from 1994 to 2023. Four cases of penile abnormalities were identified and included three types of penile abnormalities: one case of frenulum persistence, one case of paraphimosis, and two cases of penile–preputial adherence. Their clinical presentation and treatment are described here. The diagnostic workup for each case involved a combination of physical examinations and anesthesia-assisted evaluations. Treatment strategies varied depending on the specific penile abnormality, but all included surgical intervention and supportive care. Through these case reports, it becomes evident that penile abnormalities in cheetahs, while rare, can manifest in different forms. Underlying causes are as yet unknown for the cheetah. Breeding decisions need to be tailored to individual cases and include consideration of the overall genetic value of the individual to the population relative to the risk of the abnormality potentially including an inheritable component. Penile abnormalities have the potential to affect the reproductive health and overall well-being of affected animals; hence early detection, accurate diagnosis, and timely interventions are crucial for successful management and treatment. These multiple case reports emphasize the need for further research on penile abnormalities in cheetahs to enhance our understanding of the underlying causes, risk factors, and potential long-term implications.

Mycobacterium tuberculosis (M. tb) infection was diagnosed in 16 human-managed Asian elephants (Elephas maximus) at four different US facilities. A retrospective review was performed to collate information on serological test results and describe the timelines from exposure to an elephant known to be positive for M. tb, detection of antimycobacterial antibodies in the exposed elephant, and M. tb isolation from the exposed elephant to confirm diagnosis. Seroconversion was defined by a positive test result using ElephantTB STAT-PAK, multiantigen print immunoassay, or DPP VetTB assay for elephants (Chembio Diagnostic Systems, Inc). Fifteen elephants were adults (age ≥24 yr) at first seroconversion and 26 yr or older when confirmed by a positive M. tb culture. Six animals were diagnosed postmortem, and 10 were diagnosed antemortem by positive trunk wash (TW) culture. The interval between last known exposure to an M. tb–positive elephant and serological conversion was 8.5 yr (median; range 0–18 yr) in the eight animals that had not already seroconverted. The median time from seroconversion to isolation of M. tb was 2.8 yr in elephants diagnosed by TW culture (antemortem) compared with those diagnosed postmortem (median 1.2 yr). Of the 10 elephants diagnosed antemortem, four were seropositive for 14 or more yr (range 0–33 yr) prior to the M. tb–positive culture. The median number of negative TW samples submitted between seroconversion and diagnosis by culture was 16 (range 0–151 samples). In contrast, a median of 48 negative TW cultures and 10 yr elapsed (range 0–41 yr) between exposure and culture diagnosis. Although this descriptive report has limitations, these findings are useful for veterinarians faced with an M. tb–seropositive elephant. This report supports the recommendation of increasing TW surveillance if an elephant has a history of exposure to an M. tb–positive elephant and has multiple seropositive results.

Chronic gastric instability (CGI), potentially part of the gastric dilatation and volvulus (GDV) syndrome, was identified in four free-ranging Virginia opossums (Didelphis virginiana) treated at the Wildlife Rehabilitation Center of Minnesota in Roseville, Minnesota. These individuals displayed lack of expected weight gain, inappetence, gastric gas distension, and delayed gastric emptying time. One was diagnosed with GDV via diagnostic radiology, whereas the other three were diagnosed with suspected CGI using radiographs, ultrasound, and confirmed with exploratory surgery. Clinical signs fully resolved after surgical intervention and supportive management in all four cases. This case series illustrates the clinical signs, diagnostics, and treatment of CGI in Virginia opossums.

Yersiniosis due to Yersinia psuedotuberculosis can be associated with high morbidity and mortality in various species and has been a cosmopolitan management challenge in zoological institutions. This gram-negative, environmental bacterium thrives in cold, wet conditions and poses a risk to zoo species. Outbreaks can be costly and impact conservation efforts through loss of threatened and endangered species. Antemortem or clinical diagnosis can be challenging due to intermittent fecal shedding and nonspecific clinical signs. This case series describes common clinical presentations, typical postmortem findings, and response to treatment and prophylaxis at four North American zoological institutions. In total, five outbreaks occurred at four institutions during the winter months from 2013 to 2021. Artiodactyls were by far the most common species involved, and clinical signs included separation from the herd, lethargy, diarrhea, and unexpected death. Other species affected in these outbreaks included cheetahs (Acinonyx jubatus), a great-tailed grackle (Quiscalus mexicanus), a rainbow lorikeet (Trichoglossus moluccanus), and a squirrel monkey (Saimiri sciureus). Necrotizing enteritis with sepsis and pneumonia were common postmortem findings. Mortality rates were originally 76.7%, and herd prophylaxis with a third-generation cephalosporin reduced these rates. These data describe the observational and diagnostic tools to aid in timely diagnosis of a Yersinia outbreak across taxa. Aggressive treatment or prophylaxis were shown to improve survival rates.

Red pandas (Ailurus fulgens) are endangered with extinction due to deforestation and habitat fragmentation. Reported causes of unexpected death in managed red pandas include kidney, liver, gastrointestinal, and cardiac disease. A previously undetailed syndrome, red panda peracute mortality syndrome, may be emerging, as red pandas have died unexpectedly, with no clear cause of death identified at necropsy. This case series describes the clinical and postmortem findings of five red pandas at Brookfield Zoo with abnormal adrenal size and associated histologic lesions as possible contributing factors to acute death. Antemortem clinical signs consisted of thin body condition, vomiting, intermittent diarrhea, neck ventroflexion, ataxia, and electrolyte abnormalities. Mortality may have been due to abnormal adrenal function, resulting in fatal electrolyte disturbances. Antemortem adrenocorticotropic hormone (ACTH) stimulation tests indicated an inappropriate response to ACTH with persistently low cortisol and aldosterone levels after cosyntropin administration. Clinical improvement was seen when red pandas were provided steroids, but all cases were eventually fatal. Further study is needed to understand red panda peracute mortality syndrome and associated adrenal dysfunction.

In captivity, neotropical Seba's short-tailed bats (Carollia perspicillata) (Chiroptera: Phyllostomidae) reproduce readily, and contraception can constitute an opportunity to prevent uncontrolled reproduction, which can lead to overpopulation as well as inbreeding. The authors developed a safe and efficient work flow, anesthetic, and surgical castration protocol for the reproductive control of a captive population of more than 500 bats housed at the rainforest house at the Vienna Zoo, Austria. An anesthetic protocol using 0.003 mg medetomidine per bat (approximately 0.18 mg/kg) and 0.3 mg ketamine per bat (approximately 18 mg/kg) achieved surgical anesthesia in 323/328 bats, with the remaining five requiring supplementation with isoflurane. A single bat, which had a pre-existing underlying infection, died during anesthetic induction. Standard closed orchiectomy was performed on a total of 336 bats. The practicable and safe working protocol developed required three veterinarians and 3–4 assistants for the orchiectomy of this large group of captive bats. With the described work flow, the period for castration averaged 2.38 min/bat, resulting in managing 28.2 bats/h.

A one-year-old female Eastern black-and-white Colobus (Colobus guereza) was evaluated after tangling its right forelimb in exhibit netting. Radiographs of the right forelimb revealed craniolateral luxation of the radial head and a complete transverse fracture of the proximal ulna, otherwise known as a type III Monteggia fracture. Open reduction was performed and a locking cuttable bone plate was placed to address the ulnar fracture. The reduced radial head was maintained by the placement of a Mini Tightrope Fixation System. Rapid return to normal activity was observed. Radiographs taken four weeks post-operatively showed healing of the fracture as well as appropriate articulation of the radial head. At three years post-operatively, the Colobus continued to demonstrate normal ambulation without evidence of growth disruption. This is the first documented report of this specific surgical technique and implant in an exotic species.