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Background: Leopard sharks ( Triakis semifasciata ) are abundant, coastal, eastern Pacific, mesopredatory sharks and are frequently managed in aquariums and zoos. Medical examinations are a routine part of good husbandry practices, but the handling protocols vary greatly between facilities. In this study, we compared the physiological stress responses of T. semifasciata associated with manual restraint and sedated handling under parallel holding and handling procedures in a 10 min interval., Methods: Blood was collected and analyzed for the hematocrit (Hct), lactate, glucose, beta-hydroxybutyrate (β-HB), pH, blood gasses, 1α-hydroxycorticosterone (1α-OHB), and corticosterone (B)., Results: Overall, a minimal physiological stress response was observed in both groups. However, statistically significant increases in the PCO 2 , β-HB and lactate occurred, while the pH TC , SO 2 , and BE decreased over time in the manual-restraint group. In the sedated group, the B, PCO 2 , and lactate increased while the pH TC , SO 2 , and base excess (BE) decreased over time. When comparing treatments, the sedated group had a higher B and PCO 2 TC and a lower pH TC , BE, and SO 2 than the manual-restraint group at the second time point., Conclusions: This study indicates that manual restraint is comparable to the described sedation in T. semifasciata for minimally invasive procedures. The overall results show that this species had low physiological stress responses to both methods.

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.

Objective: The anti-GnRH immunotherapeutic product Improvest was administered to intact male large flying foxes (Pteropus vampyrus) under managed care for androgen mitigation, leading to a decrease in agonistic behaviors, falls, and injuries from conspecific attention., Animals: 12 males were included in this study., Procedures: Eleven bats received subcutaneous (SC) Improvest interscapular, and 1 animal received Improvest SC in its leg. Assessments included clinical presentation, treatment, behavior, and urine and fecal glucocorticoid metabolites and testosterone (T5) concentrations., Results: Eleven of the 12 bats developed reactions, which included facial edema, localized irritation, swelling of the head and neck, and pruritus with varying degrees of skin ulceration and subsequent necrosis. Three of the animals required extensive treatments, and the 1 animal who received the injection in its leg was unaffected. Posttreatment, fecal glucocorticoid metabolite and/or T5 values were at or below the nonbreeding season baseline for 3 successive breeding seasons, and there was a reduction in agonistic interactions, falls, and injuries., Clinical Relevance: A behavioral characteristic of this species is to focus on areas of irritation that exacerbated the extent of the skin wounds. Some cases required medical, surgical, and behavioral intervention. Large flying foxes may be particularly sensitive to this immunotherapeutic when given subcutaneously in the interscapular region. Despite this reaction, the positive long-term effects on behavior and multiyear reduction of hormones suggest that the use of this immunotherapeutic warrants further investigation, although the results should be taken into consideration with other factors such as handling, treatments, chronicity of lesions.

This study investigated the reproductive biology and sperm cryopreservation of ex situ southern stingrays ( Hypanus americanus ) by semen collection and characterization and the development and validation of an enzyme-linked immunoassay for plasma total testosterone. Semen was collected in March and June using a manual massage technique, and the ejaculates were assessed for volume, pH, osmolarity, motility, status (0-5 scale: 0 = no forward progression, 5 = rapid linear progression) and total sperm count. Semen was extended in Hank's elasmobranch ringer solution containing 10% DMSO, 10% glycerol or 5% glycerol with 5% N-methylformamide and cryopreserved using a conventional freezing method (~-50 °C/min) or a modified slow freezing method (~-3 °C/min). Body condition was scored from 1-5 and was noted to be low in March (1.93 ± 0.07) due to feeding practices and increased by June (2.93 ± 0.05) after dietary corrections were made. A concomitant increase ( p < 0.05) in plasma total testosterone concentration and sperm motility was noted between March (8.0 ± 7.2 ng/mL, 5.71 ± 2.77%) and June (97.3 ± 11.3 ng/mL, 51.4 ± 14.3%). Samples cryopreserved using a modified slow freeze method (~-3 °C/min) had higher post-thaw motility and plasma membrane integrity than conventionally cryopreserved samples. Data indicate that southern stingray sperm morphometrics adheres to those of other elasmobranch species and that a slow cooling rate may be an avenue of research to improve southern stingray sperm survival during cryopreservation.

The increasing frequency and duration of marine heatwaves attributed to climate change threatens coastal elasmobranchs and may exacerbate existing anthropogenic stressors. While the elasmobranch stress response has been well studied, the role of the unique corticosteroid-1α-hydroxycorticosterone (1α-OHB)-in energy balance is not understood. Therefore, 1α-OHB's utility as a stress biomarker in elasmobranch conservation physiology is equivocal. Here, we analyse the roles of corticosteroids, 1α-OHB and corticosterone, and metabolites, glucose and 3-hydroxybutyrate (3-HB), in response to stress in a protected tropical shark species, the blacktip reef shark ( Carcharhinus melanopterus ). Wild-caught neonates were exposed to ambient (27°C) or heatwave conditions (29°C) and subsequently a simulated fishing stressor (1 min air exposure). Blood samples were taken prior to temperature exposure, prior to air exposure, and 30 min, 1 h, 24 h, and 48 h post-air exposure at treatment temperatures. Plasma 1α-OHB was elevated for 48 h in 27°C-exposed sharks but declined over time in 29°C-exposed sharks. Plasma 1α-OHB was not correlated with either metabolite. Plasma glucose was higher and plasma 3-HB was lower in 29°C-exposed sharks. In a separate experiment, blood samples were collected from both neonate and adult sharks immediately following capture and again 5 min later, and analysed for corticosteroids and metabolites. Plasma 1α-OHB increased in neonates within 5 min, but neonates displayed lower plasma 1α-OHB and higher glucose concentrations than adults. We conclude that 1α-OHB does not serve as a classic glucocorticoid role in C. melanopterus under these stressors. Furthermore, we show for the first time, ontogenetic differences in plasma 1α-OHB. Ultimately, our findings provide insights into hormonal control of energy mobilization during stress in C. melanopterus , particularly during simulated heatwave conditions, which seem to alter both endocrine and energy mobilization. Further work is needed to determine the utility of 1α-OHB as a biomarker for the mobilization of energy during a stress event in elasmobranchs., (© The Author(s) 2021. Published by Oxford University Press and the Society for Experimental Biology.)

Critically endangered black rhinoceros (BR) under human care are predisposed to non-hemochromatosis Iron Overload Disorder (IOD). Over the last 30 years, BR have been documented with diseases that have either been induced by or exacerbated by IOD, prompting significant efforts to investigate and address this disorder. IOD is a multi-factorial chronic disease process requiring an evidence-based and integrative long-term approach. While research continues to elucidate the complexities of iron absorption, metabolism, and dysregulation in this species, preventive treatments are recommended and explained herein. The aim of this report is to highlight the accumulated evidence in nutrition, clinical medicine, and behavioral husbandry supporting the successful management of this disorder to ensure optimal animal health, welfare, and longevity for a sustainable black rhinoceros population.

The objective of this study was to document the pharmacokinetics of ketoprofen following 3 mg/kg intramuscular (IM) and intravenous (IV) injections in rainbow trout ( Oncorhynchus mykiss ) and 8 mg/kg intramuscular (IM) injection in Nile tilapia ( Oreochromis niloticus) . Plasma was collected laterally from the tail vein for drug analysis at various time intervals up to 72 h following the injection of ketoprofen. In trout, area under the curve (AUC) levels were 115.24 μg hr/mL for IM and 135.69 μg hr/mL for IV groups with a half-life of 4.40 and 3.91 h, respectively. In both trout and tilapia, there were detectable ketoprofen concentrations in most fish for 24 h post-injection. In tilapia, there was a large difference between the R- and S-enantiomers, suggesting either chiral inversion from R- to S-enantiomer or more rapid clearance of the R-enantiomer. AUC values of the S- and R-enantiomers were 510 and 194 μg hr/Ml, respectively, corresponding to a faster clearance for the R-enantiomer. This study shows that there were very high plasma concentrations of ketoprofen in trout and tilapia with no adverse effects observed. Future studies on the efficacy, frequency of dosing, analgesia, adverse effects, and route of administration are warranted., (Copyright © 2020 Greene, Mylniczenko, Storms, Burns, Lewbart, Byrd and Papich.)

Objective: To characterize physical examination, plasma biochemical, and ultrasonographic findings in aquarium-housed, managed semiwild, and wild southern stingrays ( Hypanus americanus ) with and without reproductive disease., Animals: Southern stingrays from aquarium (n = 48), lagoon (managed semiwild; 34), and wild (12) habitats., Procedures: Limited, opportunistic prosections were performed of presumed anatomically normal wild southern stingrays and compared with findings for aquarium-housed stingrays with reproductive disease. Ultrasonographic video data from both groups were used to assign a score (1 to 5) indicating increasing severity of ovarian and uterine reproductive disease. Plasma total 17β-estradiol, estrone, progesterone, and testosterone concentrations were measured with enzyme immunoassays validated for use in southern stingrays., Results: Ultrasonographic ovarian scores were significantly correlated with uterine scores. No reproductive disease was detected in semiwild or wild stingrays, but 65% (31/48) of aquarium-housed stingrays had developing or advanced reproductive disease (ie, ultrasonographic ovarian or uterine score of 4 or 5). Significant correlations were identified between ovarian and uterine disease status and plasma concentrations of all steroid hormones except testosterone., Conclusions and Clinical Relevance: Findings suggested that ultrasonography and plasma hormone concentrations may be useful in the identification of reproductive disease and determination of disease severity in southern stingrays.

Differences in reported testosterone concentrations in male sea turtle blood samples are common in the veterinary literature, but may be accounted for by differences in sample handling and processing prior to assay. Therefore, our study was performed to determine best practices for testosterone analysis in male sea turtles (Caretta caretta and Chelonia mydas). Blood samples were collected into 5 collection tube types, and assay validation and measured testosterone concentrations were compared across different sample storage (fresh, refrigerated 1 week, or frozen), extraction (unextracted or ether-extracted), and processing treatment (untreated, homogenized, or dissociation reagent) conditions. Ether-extracted and dissociation reagent-treated samples validated in all conditions tested and are recommended for use, as unextracted samples validated only if assayed fresh. Dissociation reagent treatment was simpler to perform than ether extraction and resulted in total testosterone concentrations ~2.7-3.5 times greater than free testosterone measured in ether-extracted samples. Sample homogenization did not affect measured testosterone concentrations, and could be used to increase volume in gelled samples. An annual seasonal testosterone increase was observed in both species when ether extraction or dissociation reagent treatment was used. Annual deslorelin implant treatments in a Chelonia mydas male resulted in suppression of seasonal testosterone following the fourth treatment. Seasonal testosterone patterns resumed following discontinuation of deslorelin. Comparison of in-house and commercially available enzyme immunoassay kits revealed similar patterns of seasonal testosterone increases and deslorelin-induced suppression. Our study highlights the importance of methodological validation and provides laboratorians with best practices for testosterone enzyme immunoassay in sea turtles., (© 2015 The Author(s).)

Objective: To establish reference ranges for critical care blood values measured in wild and aquarium-housed elasmobranchs by use of a point-of-care (POC) blood analyzer and to compare values on the basis of species category (pelagic, benthic, or intermediate) and phlebotomy site., Design: Cross-sectional study., Animals: 66 wild and 89 aquarium-housed elasmobranchs (sharks and rays)., Procedures: Aquarium-housed elasmobranchs were anesthetized for sample collection; wild elasmobranchs were caught via hook and line fishing, manually restrained for sample collection, and released. Blood was collected from 2 sites/fish (dorsal sinus region and tail vasculature) and analyzed with the POC analyzer. Reference values of critical care blood analytes were calculated for species most represented in each population. Values were compared on the basis of species categorization (pelagic, intermediate, or benthic) and collection site., Results: Oxygen saturation and circulating concentrations of lactate and glucose were significantly different among aquarium-housed pelagic, intermediate, and benthic species. Lactate concentration was significantly different among these categories in wild elasmobranchs. Significant differences were detected between samples from the 2 collection sites for all blood analytes. In both study populations, pH and lactate values were infrequently < 7.2 or > 5 mmol/L, respectively., Conclusions and Clinical Relevance: Brevity of handling or chemical restraint may have reduced secondary stress responses in fish because extreme variations in blood analyte values were infrequent. Sample collection site, species categorization, acclimation to handling, and restraint technique should be considered when assessing values obtained with the POC analyzer used in this study for blood analytes and immediate metabolic status in elasmobranchs.

Marked renal vascular changes, suggestive of hypertension, were present in adult western gray kangaroos (Macropus fuliginosus) from a single facility over a 14-year period. A subset of these kangaroos also had vague clinical nervous system deficits, including blindness. To characterize the vascular lesions, determine prevalence, and document other changes, case histories and archival tissue sections from 21 adult kangaroos (8 male, 13 female) that died or were euthanatized between 1994 and 2008 were reviewed. Relevant lesions included increased thickness of the renal arteriolar tunica media with smooth muscle hypertrophy and/or hyperplasia, accumulation of extracellular matrix within arterioles, increased vascular tortuosity, and varying degrees of juxtaglomerular hyperplasia. Renal tissue from two more severely affected animals was further examined by transmission electron microscopy, highlighting arteriolar endothelial cell hypertrophy and disruption of the medial architecture. Hypertrophy of arteries and arterioles in other organ systems was also present (3/21), including vessels in the brain and spinal cord of one animal with clinical neurologic signs. Four kangaroos had antemortem retinal detachment, a potential sequel of hypertension in humans and domestic mammals. The cause of these vascular lesions in this mob is uncertain. Lesions were not associated with an infectious disease process, age, underlying renal disease, or thyroid abnormalities. In the absence of other causes, hypertension was a differential. Further investigation into clinical significance and predisposing factors, such as genetics and diet, is warranted.

Fatal colonic obstructions were diagnosed in three captive, adult, reticulated giraffe (Giraffa camelopardalis reticulata). Clinical presentations varied, but all cases displayed decreased activity, anorexia, and considerably decreased fecal production, consistent with intestinal obstruction. Case 1 was diagnosed at necropsy with a phytobezoar obstructing the spiral colon. Case 2 was diagnosed at necropsy with a fecal impaction of the colon. Case 3 was diagnosed during surgery with colonic ileus. Cases 2 and 3 underwent surgical intervention but were markedly compromised by the time of surgery and died during surgery or 24 hr postoperatively. Gastrointestinal obstruction, requiring aggressive supportive care and early surgical intervention, should be considered in giraffe in which anorexia and substantially decreased fecal production are observed. Abdominal exploratory surgery will likely be necessary for diagnosis and treatment. Based on a small number of cases, gastrointestinal obstruction has a poor prognosis in giraffe.

A captive harbor seal (Phoca vitulina) presented with partial anorexia, ataxia, and head bobbing, which progressed to complete anorexia, lethargy, and persistent whole-body intention tremors within several days. Response to treatment with ponazuril, serology, and cerebrospinal fluid analysis supported a diagnosis of Sarcocystis neurona. Analysis of serum levels for ponazuril indicated that therapeutic levels could be achieved at a dosage of 5 mg/kg p.o. s.i.d., whereas clinical response was improved at a dosage of 10 mg/kg. Several months after initiation of antiprotozoal therapy, the neurologic signs resolved, although rare intermittent tremors were seen with significant exertion.

Objective: To evaluate differences in Hct between 2 venipuncture sites in captive and free-ranging sharks., Animals: 32 healthy adult captive sharks (Carcharhinus melanopterus, Carcharhinus plumbeus, Stegastoma fasciatum, Orectolobus japonicus, and Triaenodon obesus) and 15 captured free-ranging adult sharks (Carcharhinus limbatus and Carcharhinus acronotus)., Procedures: Blood samples were collected from the caudal tail artery followed by collection from the sinus located immediately caudal to the cranial dorsal fin. The Hct was determined for each sample and results were compared. Additionally, results for sharks that were highly active and used aerobic metabolism were compared with results for sharks that were less active and tolerant of anaerobic conditions., Results: Mean Hct for all sharks was significantly less (8% less) in blood samples obtained from the cranial dorsal fin sinus, compared with the Hct for samples obtained from the caudal tail artery. When compared on the basis of metabolic class, sharks that were more tolerant of anaerobic conditions had lower Hct values and smaller differences between the 2 venipuncture sites., Conclusions and Clinical Relevance: Hct values were significantly lower in blood samples collected from the cranial dorsal fin sinus compared with values for samples collected from the caudal tail artery. It is important to recognize this difference when evaluating hematologic variables in sharks and when establishing reference ranges for Hcts for shark populations. Sharks that were more active and relied on aerobic metabolism had higher Hct values than did anaerobic-tolerant sharks, and the difference in Hct values between venipuncture sites was more pronounced.

An adult, female Malayan sun bear (Helarctos malayanus) was diagnosed with squamous cell carcinoma of the rostral mandible. Initial treatment included bilateral mandibulectomy rostral to the lingual frenulum followed by intra- and perilesional cisplatin injections. Recovery after the procedure was uneventful and the Malayan sun bear adapted well to a shortened mandible. Histopathology indicated incomplete surgical excision of the tumor; therefore, radiation therapy was instituted weekly for four treatments at 2 Gy in parallel opposed fields (total 4 Gy each treatment) with one additional cisplatin treatment. Two years after initial presentation, the animal showed no recurrence of neoplasia.