RELATIONSHIP BETWEEN REPRODUCTIVE AND BONE BIOMARKERS AND OSTEOARTHRITIS IN ZOO ASIAN (ELEPHAS MAXIMUS) AND AFRICAN (LOXODONTA AFRICANA) ELEPHANTS.

Osteoarthritis (OA) is common in zoo Asian (Elephas maximus) and African (Loxodonta africana) elephants. This study investigated the relationship between confirmed or suspected OA with ovarian cyclicity, gonadotropins, progestagens, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and collagen type I (CTX-I) in zoo elephants. In Asian elephants, odds of having confirmed or suspected OA decreased with cycling (OR = 0.22, P = 0.016; OR = 0.29, P = 0.020, respectively), however, not when adjusted for age (odds ratio [OR] = 0.31, P = 0.112; OR = 0.58, P = 0.369, respectively). In African elephants, none of the models between confirmed OA and cycling status were significant (P > 0.060), while the odds of having suspected OA decreased with cycling (OR = 0.12, P = 0.001), even after adjusting for age (OR = 0.15, P = 0.005). Progestagens (Asian elephants P > 0.096; African elephants P > 0.415), LH (Asian P > 0.129; African P > 0.359), and FSH (Asian P > 0.738; African P > 0.231) did not differ with confirmed or suspected OA status, unadjusted. CTX-I concentrations were not related to OA status (P > 0.655). This study concluded hormonal changes may not have a strong impact on OA, so additional investigation into other serologic biomarkers is warranted.

Patterns of serum immune biomarkers during elephant endotheliotropic herpesvirus viremia in Asian and African elephants.

Hemorrhagic disease (HD) caused by a group of elephant endotheliotropic herpesviruses (EEHV) is one of the leading causes of death for young elephants in human care. These viruses are widespread and typically persist latently in adult elephants with no negative effects; however, in juvenile Asian and more recently young African elephants, the onset of disease can be rapid and the mortality rate high. Measuring biomarkers associated with the immune response could be beneficial to understanding underlying disease processes, as well as the management of infection and HD. The goal of this study was to measure acute phase proteins and cytokines in serum collected from elephants infected with EEHV (13 Asian and 1 African) and compare concentrations according to presence, severity and outcome of disease. Serum amyloid A (SAA) and haptoglobin (HP) were higher in elephants with EEHV viremia than those without; concentrations increased with increasing viral load, and were higher in fatal cases compared to those that survived. In Asian elephants, SAA was also higher during EEHV1 viremia compared to EEHV5. Cytokine concentrations were typically low, and no statistical differences existed between groups. However, in individuals with detectable levels, longitudinal profiles indicated changes in tumor necrosis factor alpha (TNF-α) and interleukin-2 (IL-2) that may reflect an immune response to EEHV infection. However, the overall low concentrations detected using previously validated assays do not support the presence of a 'cytokine storm' and suggest more work is needed to understand if sub-optimal immune responses could be involved in disease progression. These results highlight the potential benefit of measuring circulating biomarker concentrations, such as APPs and cytokines, to improve our understanding of EEHV viremia and HD, assist with monitoring the progression of disease and determining the impact of interventions.

SPINAL NEMATODIASIS IN A LINED FLAT-TAIL GECKO (UROPLATUS LINEATUS).

A 5-y-old female lined flat-tail gecko (Uroplatus lineatus) presented for acute onset of lethargy and paraplegia and was subsequently euthanized. Histologic examination of the spinal cord revealed a verminous myelitis comprising moderate, multifocal, necrotizing myelitis with intramedullary adult and larval nematodes. Molecular data and morphology indicate a cosmocercid nematode, most likely of the genus Raillietnema, a diverse taxon reported to parasitize reptiles, amphibians, and teleost fish. To the authors' knowledge this is the first report of spinal nematodiasis in a reptile species, and the first report of spinal parasitism causing hind-limb paraplegia in a reptile.

USE OF INTRACARPAL INTERLEUKIN RECEPTOR ANTAGONIST PROTEIN (IRAP) AND HYALURONIC ACID IN A MULTIMODAL THERAPEUTIC REGIME FOR OSTEOARTHRITIS IN AN ASIAN ELEPHANT (ELEPHAS MAXIMUS).

An approximately 41-yr-old female Asian elephant (Elephas maximus) experiencing forelimb stiffness and decreased range of motion was diagnosed with bilateral carpal osteoarthritis (OA). Standing sedation combined with local anesthesia was used to deliver ultrasound-guided carpal articular injections of an autologous conditioned serum product, interleukin receptor antagonist protein, combined with hyaluronic acid. Within 2 mo of completing therapy, improved range and speed of motion were evident. Reduced inflammation was suggested by decreased carpal articular prostaglandin E2 levels. Subjectively improved clinical signs lasted approximately 5-6 mo, at which point carpal articular injections were repeated. Joint inflammatory markers were useful in gauging response to treatment and may provide guidance in the diagnostic and therapeutic approach to elephant OA. On the basis of the positive response noted, interarticular autologous therapy combined with hyaluronic acid should be considered for carpal OA in elephants.

Serum Health Biomarkers in African and Asian Elephants: Value Ranges and Clinical Values Indicative of the Immune Response.

Serum biomarkers indicative of inflammation and disease can provide useful information regarding host immune processes, responses to treatment and prognosis. The aims of this study were to assess the use of commercially available anti-equine reagents for the quantification of cytokines (tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), interleukins (IL) 2, 6, and 10) in African (Loxodonta africana, n = 125) and Asian (Elephas maximus, n = 104) elephants, and alongside previously validated anti-human reagents for acute-phase proteins (serum amyloid A and haptoglobin), calculate species-specific biomarker value ranges. In addition, we used opportunistically collected samples to investigate the concentrations of each biomarker during identified clinical cases of illness or injury, as a first step to understanding what biomarkers may be useful to managing elephant health. Immune biomarkers were each elevated above the calculated species-specific value ranges in at least one clinical case, but due to variability in both clinical and non-clinical samples, only serum amyloid A was significantly higher in clinical compared to non-clinical paired samples, with tendencies for higher TNF-α and IL-10. We also detected increased secretion of serum amyloid A and all five cytokines following routine vaccination of a single Asian elephant, indicating that these biomarkers can be beneficial for studying normal immune processes as well as pathology. This study indicates that assays developed with commercial reagents can be used to quantify health biomarkers in wildlife species and identifies several that warrant further investigation to elucidate immune responses to various pathologies.

REVIEW OF ANESTHETIC PROTOCOLS IN ANDEAN BEARS (TREMARCTOS ORNATUS), SLOTH BEARS (MELURSUS URSINUS), AND GIANT PANDAS (AILUROPODA MELANOLEUCA) AT THE SMITHSONIAN INSTITUTION'S NATIONAL ZOOLOGICAL PARK, 1995-2016.

A review of anesthetic procedures used in Andean bears (Tremarctos ornatus), sloth bears (Melursus ursinus), and giant pandas (Ailuropoda melanoleuca) housed at the Smithsonian Institution's National Zoological Park (NZP) from 1995 to 2016 was performed. A total of 146 anesthetic procedures (55 procedures on 12 Andean bears, 38 procedures on nine sloth bears, and 53 procedures on five giant pandas) occurred at NZP during this time frame. Induction protocols involved some combination of ketamine (K; n = 121), tiletamine-zolazepam (TZ; n = 91), medetomidine (M; n = 67), xylazine (X; n = 42), midazolam (Mid; n = 9), and butorphanol (B; n = 1). The most commonly used protocols were TZKM for both Andean bears (n = 29) and sloth bears (n = 12), and KX in giant pandas (n = 17). Supplemental injections of K, TZ, Mid, or M were required to complete inductions in 66 cases (45%). Anesthetic maintenance was most often completed with isoflurane, ketamine, or propofol. The most commonly reported complications included perianesthetic emesis (n = 47), ptyalism (n = 16), and seizure-like activity (n = 11). The most frequent physiologic findings included low pulse oximetry values (n = 95), bradycardia (n = 95), hypothermia (n = 74), and hypertension (n = 55). Dose ranges, induction, and recovery times, supplementation and complication rates, and physiologic values are reported for each protocol by species.

Longitudinal fecal hormone monitoring of adrenocortical function in zoo housed fishing cats (Prionailurus viverrinus) during institutional transfers and breeding introductions.

The ex situ population of fishing cats (Prionailurus viverrinus) has become increasingly important for the conservation of this species. Unfortunately, captivity-induced stress is a concern and potential factor for lack of breeding success in this small felid, resulting in an unsustainable population. The objectives of this study were to: 1) validate an enzyme immunoassay for monitoring of fecal glucocorticoid metabolite (FGM) concentrations in the fishing cat; 2) identify potential exogenous stressors in the captive environment; 3) pinpoint management techniques that may lower FGM concentrations; and 4) determine if FGM concentrations are related to breeding success. Through a successful adrenocorticotrophic hormone challenge and additional laboratory methods, a cortisol enzyme immunoassay was validated as an effective tool for detecting FGM in this species. Between 2010 and 2013, longitudinal FGM monitoring was conducted in 26 fishing cats in the North American Species Survival Plan®. Exogenous stressors that elevated FGM concentrations included: chemical immobilizations; permanent transfers between facilities; construction; facility events; and fights/aggression among breeding pairs. Management factors that lowered FGM concentrations included: increased animal-keeper interaction through formal training; and providing indoor, off-exhibit, holding areas. In addition, social housing of individuals (either established breeding pairs or same sex pairs) decreased FGM concentrations. Individuals with breeding success (defined as observed copulations during the study period) also had lower FGM concentrations than unsuccessful individuals. Findings indicate that management factors play a role in lowering glucocorticoid (stress) levels in fishing cats, which may ultimately affect breeding success in the ex situ population.

COMPARISON OF ISOFLURANE GAS VERSUS A GUAIFENESIN, KETAMINE, AND MEDETOMIDINE CONSTANT-RATE INFUSION FOR MAINTENANCE ANESTHESIA IN AMERICAN BLACK BEARS (URSUS AMERICANUS).

Published anesthetic protocols for captive and free-ranging bears are limited to injectable inductions with maintenance via inhalants or additional injectable boluses. Though common in other species, intravenous (IV) continuous-rate infusions (CRI) using guaifenesin combinations have not been evaluated in ursids. This study evaluated the use of a CRI compared to an inhalant for maintenance anesthesia. Seven healthy American black bears (Ursus americanus) were anesthetized in a crossover design with two different anesthetic maintenance protocols. Bears were immobilized with ketamine (2.02 ± 0.14 mg/kg) and medetomidine (0.04 ± 0.003 mg/kg) for both protocols. The anesthetic maintenance control protocol consisted of isoflurane gas (ISO) started at 2% delivered by endotracheal tube; the experimental protocol consisted of guaifenesin, medetomidine, ketamine (GMK) IV CRI started at 50 mg/kg/hr guaifenesin, 0.01 mg/kg/hr medetomidine, and 1 mg/kg/hr ketamine. Induction and recovery parameters including time to first effect, recumbency, and hands on; duration of maintenance protocol; and time from reversals administered to head up, standing on all four feet, no ataxia, and to fully recovered were recorded and compared between protocols. Heart rate, respiratory rate, rectal temperature, blood pressure, end tidal carbon dioxide, and hemoglobin oxygen saturation were recorded at 5-min intervals and compared between protocols. Venous blood gases were obtained at the start, middle, and end of the maintenance anesthesia and compared between protocols. All bears exhibited hypertension with mild respiratory acidosis throughout procedures. Measured physiologic parameters did not differ significantly between the isoflurane and the GMK CRI maintenance protocols, with the exception of higher endpoint (ISO) pCO2 measurements. No adverse events were recorded with either protocol, and adequate depth of anesthesia was maintained with both protocols. GMK CRI provides a safe, effective, and more portable alternative to inhalant anesthetics for maintenance anesthesia in bears in captivity or in the field.

BATRACHOCHYTRIUM DENDROBATIDIS IN A CAPTIVE COLLECTION OF GREEN SALAMANDERS ( ANEIDES AENEUS), LONG-TAILED SALAMANDERS ( EURYCEA LONGICAUDA), AND TWO-LINED SALAMANDERS ( EURYCEA BISLINEATA).

A chytridiomycosis outbreak from Batrachochytrium dendrobatidis ( Bd) in a mixed-species plethodontid salamander exhibit resulted in four green salamander ( Aneides aeneus) deaths. One green salamander died before treatment, and three died during treatment with daily 0.005% itraconazole baths. All salamanders had evidence of severe Bd infections via cytology, histopathology, and/or polymerase chain reaction (PCR) at the time of death. Ten long-tailed salamanders ( Eurycea longicauda) and one two-lined salamander ( Eurycea bislineata) that shared the enclosure were initially negative for Bd on quantitative PCR but were prophylactically treated with daily 0.01% itraconazole baths for 11 days. Posttreatment testing yielded eight long-tailed salamanders and one two-lined salamander positive for Bd with low gene equivalents. All salamanders were negative after two to three treatment courses, and there were no additional mortalities. The difference in mortality and fungal load suggested that genus Aneides salamanders may be more susceptible to Bd than genus Eurycea salamanders.

PHARMACOKINETICS OF A SINGLE DOSE OF METRONIDAZOLE AFTER RECTAL ADMINISTRATION IN CAPTIVE ASIAN ELEPHANTS (ELEPHAS MAXIMUS).

Metronidazole is a nitroimidazole antibacterial and antiprotozoal drug with bacteriocidal activity against a broad range of anaerobic bacteria. It is a recognized treatment for elephants diagnosed with anaerobic bacterial infection or protozoal disease or exhibiting signs of colonic impaction, diarrhea, and colic. This study evaluated the pharmacokinetics of rectally administered metronidazole (15 mg/kg) in five adult female Asian elephants (Elephas maximus). Serum samples were collected from each animal for 96 hr after rectal administration of metronidazole. Serum concentrations of metronidazole and its primary metabolite, hydroxymetronidazole, were measured via ultraperformance liquid chromatography. Data were analyzed via a noncompartmental pharmacokinetic approach. Results indicated that serum levels of metronidazole were quantifiable at the 0.25 hr time point and absent in all elephants by the 96 hr time point. The serum peak concentration (mean ± SD, 13.15 ± 2.59 µg/ml) and area under the curve from time 0 to infinity (mean ± SD, 108.79 ± 24.77 hr × µg/ml) were higher than that reported in domestic horses after similar usage. Concurrently, the time of maximum serum concentration (mean ± SD, 1.2 ± 0.45 hr) and terminal elimination half-life (harmonic mean ± pseudo-SD, 7.85 ± 0.93 hr) were longer when compared to equine reports. Rectal administration of metronidazole was well tolerated and rapidly absorbed in all study elephants. Based on the findings in this study, metronidazole administered at a single dose of 15 mg/kg per rectum in the Asian elephant is likely to result in serum concentrations above 4 µg/ml for 8 hr and above 2 µg/ml for 24 hr after treatment is administered. Dosing recommendations should reflect the mean inhibitory concentration of metronidazole for each pathogen.

Evaluation of captive gibbons (Hylobates spp., Nomascus spp., Symphalangus spp.) in North American Zoological Institutions for Gibbon Ape Leukemia Virus (GALV).

This study evaluated 79 captive gibbons (Hylobates, Nomascus, and Symphalangus spp.) within 30 North American zoological institutions for evidence of exposure to and possible infection with gibbon ape leukemia virus (GALV). Enzyme-linked immunosorbent assays (ELISAs) on gibbon serum samples revealed the presence of antibodies against GALV antigens in 28% of animals, indicating previous exposure or possibly protective immunity to GALV. Virus detection in gibbon blood or serum using polymerase chain reaction (PCR) or co-culture of gibbon peripheral blood mononuclear cells with human cells was negative for all samples submitted. The majority (19/27, 70%) of animals with reported health conditions were clinically healthy at the time of sample collection. Historically accrued clinical data were used to assess association of diseases in gibbons antibody positive for GALV. The results suggest captive gibbons could mount an immune response to GALV and show no evidence of infection. There was no association with neoplastic conditions in seropositive animals. The potential role of gibbons as a reservoir for GALV and the role of GALV as an epizoonotic-zoonotic agent or as a contributor to gibbon ape morbidity and mortality are not substantiated by the study findings.

Hepatocellular carcinoma in captive slender tailed meerkats (Suricata suricatta): 5 cases.

Hepatocellular carcinoma was diagnosed in five slender tailed meerkats (Suricata suricatta) housed at the Smithsonian Institution's National Zoological Park between 1980 and 2013. Animals included four females and one male, ranging from 7 to 15 yr of age. Common clinical signs included weight loss and lethargy. Three of the neoplasms originated from the right medial liver lobe and were located adjacent to or partially incorporated in the gall bladder. Three animals had solitary masses, and two animals had multiple hepatic masses; all were characterized by polygonal to round neoplastic hepatocytes arranged in a trabecular pattern with smaller regions of varied solid, adenoid, and rarely peliod cell patterns. Hemorrhage and necrosis often with cystic degeneration was noted in all five cases. There was no evidence of metastatic disease in any of the cases examined.

Blood mineral concentrations in manatees (Trichechus manatus latirostris and Trichechus manatus manatus).

Limited information is available regarding the role of minerals and heavy metals in the morbidity and mortality of manatees. Whole-blood and serum mineral concentrations were evaluated in apparently healthy, free-ranging Florida (Trichechus manatus latirostris, n = 31) and Belize (Trichechus manatus manatus, n = 14) manatees. Toxicologic statuses of the animals and of their environment had not been previously determined. Mean mineral whole-blood (WB) and serum values in Florida (FL) and Belize (BZ) manatees were determined, and evaluated for differences with respect to geographic location, relative age, and sex. Mean WB and serum silver, boron, cobalt, magnesium, molybdenum, and WB cadmium concentrations were significantly higher in BZ versus FL manatees (P < 0.05). Mean WB aluminum, calcium, manganese, sodium, phosphorus, vanadium, and serum zinc concentrations were significantly lower in BZ versus FL manatees. Adult manatees had significant and higher mean WB aluminum, manganese, sodium, antimony, vanadium, and serum manganese and zinc concentrations compared to juvenile animals. Significant and lower mean WB and serum silver, boron, cobalt, and serum copper and strontium concentrations were present in adults compared to juveniles (P < or = 0.05). Females had significant and higher mean WB nickel and serum barium compared to males (P < or = 0.05). Mean WB arsenic and zinc, and mean serum iron, magnesium, and zinc concentrations fell within toxic ranges reported for domestic species. Results reveal manatee blood mineral concentrations differ with location, age, and sex. Influence from diet, sediment, water, and anthropogenic sources on manatee mineral concentration warrant further investigation.

Proximate nutrient analyses of four species of submerged aquatic vegetation consumed by Florida manatee (Trichechus manatus latirostris) compared to romaine lettuce (Lactuca sativa var. longifolia).

Free-ranging Florida manatees (Trichechus manatus latirostris) consume a variety of sea grasses and algae. This study compared the dry matter (DM) content, proximate nutrients (crude protein [CP], ether-extracted crude fat [EE], nonfiber carbohydrate [NFC], and ash), and the calculated digestible energy (DE) of sea grasses (Thalassia testudinum, Halodule wrightii, and Syringodium filiforme) collected in spring, summer, and winter, and an alga (Chara sp.) with those of romaine lettuce (Lactuca sativa var. longifolia). Neutral-detergent fiber (NDF), acid-detergent fiber (ADF), and lignin (L) measured after ash-extraction were also compared. Results of statistical tests (C = 0.01) revealed DM content was higher in aquatic vegetation than in lettuce (P = 0.0001), but NDF and ADF were up to threefold greater, EE (P = 0.00001) and CP (P = 0.00001) were 2-9 times less, and NFC (P = 0.0001) was 2-6 times lower in sea grass than in lettuce, on a DM basis. Chara was lower in NDF, ADF, L, EE, CP, and NFC relative to lettuce on a DM basis. Ash content (DM basis) was higher (P = 0.0001), and DE was 2-6 times lower in aquatic vegetation than in lettuce. Sea grass rhizomes had lower L and higher ash contents (DM basis) than sea grass leaves. Based on the nutrient analyses, romaine lettuce and sea grasses are not equivalent forages, which suggests that the current diet of captive Florida manatees should be reassessed.

Cardiac evaluation of clinically healthy captive maned wolves (Chrysocyon brachyurus).

The objective of this project was to determine radiographic vertebral heart sizes and electrocardiographic (ECG) and echocardiographic measurements in healthy anesthetized maned wolves (Chrysocyon brachyurus). The wolves, housed at the White Oak Conservation and Smithsonian National Zoo Conservation and Research Centers, were being anesthetized for annual examinations. Cardiac auscultation, thoracic radiographs, a standard 6-lead ECG, and echocardiography were performed on the wolves while they were under general anesthesia. Thirteen maned wolves were evaluated: five males and eight females. Mean age was 6.4 +/- 4.4 years (range, 2-13 years). Mean weight was 26 +/- 2.95 kg (range, 22-32 kg). Low-grade systolic murmurs were auscultated in three of 13 maned wolves. Evaluation of ECGs revealed a sinus rhythm, with a QRS morphology, and mean electrical axis similar to domestic canines. Radiographic evaluation revealed a mean vertebral heart size of 8.27 +/- 0.48 (range, 7.9-8.6). In addition, the cardiac silhouette was seen to elongate, with an increase in sternal contact in older wolves. Echocardiography showed that mitral valve degenerative changes and insufficiency is likely common in older wolves. Visualization of physiologic regurgitation across the mitral and pulmonary valves was common in wolves of all ages. Left ventricular measurements were similar to those reported for healthy dogs, and several variables correlated well with body weight. Two wolves were found to have one to three heartworms in the right pulmonary artery, and degenerative mitral valve disease was determined in maned wolves older than 6 years of age. All of the wolves in this study were on heartworm preventative and tested negative for heartworm antigen at their annual examinations. The results of this study provide reference information for use in the cardiac evaluation of anesthetized maned wolves.

Butorphanol, azaperone, and medetomidine anesthesia in free-ranging white-tailed deer (Odocoileus virginianus) using radiotransmitter darts.

Fourteen free-ranging white-tailed deer (Odocoileus virginianus) were successfully anesthetized for a total of 15 anesthetic events using a combination of butorphanol (mean+/-SD, 0.58+/-0.1 mg/kg), azaperone (0.37+/-0.06 mg/kg), and medetomidine (0.19+/-0.03 mg/kg) (BAM) administered by radiotelemetry darts from hunting blinds between November 2006 and May 2007. Mean time to locate deer (mean+/-SD, 17. 3+/-7 min), to recumbency (21.4+/-5 min), to initiation of data acquisition (27.5+/-8 min), total down time (37+/-6 min), and average distance run (161+/-82 m) were recorded. Physiologic monitoring was done every 5 min for a total of 20 min. Arterial blood gases were collected every 10 min. Mild to moderate hypoxemia and mildly depressed ventilation occurred in some animals. Muscle relaxation and plane of anesthesia were adequate for completion of all procedures; two deer were administered intravenous butorphanol supplementation to achieve light anesthesia (mean+/-SD, 0.19 mg/kg; 0.12 mg/kg). Recovery following intramuscular administration of naltrexone (1.34+/-0.42 mg/kg; 2x butorphanol dose) and atipamezole (0.93+/-0.14 mg/kg; 5x medetomidine dose) was rapid, smooth, and complete. Mean+/-SD recovery time was 4.5+/-1.5 min. Overall efficacy of the Pneu-Dart radiotelemetry system was 65%. Negative attributes of this protocol included long induction time and dart failure. No known mortalities occurred as a result of the study. This drug combination provided safe, reliable, short-term anesthesia of free-ranging white-tailed deer. Further evaluation for use in field procedures in other cervids is warranted.

Distal limb radiography, ossification, and growth plate closure in the juvenile Asian elephant (Elephas maximus).

Eleven juvenile Asian elephants (Elephas maximus) were evaluated radiographically to determine the relative times of growth plate closure and phalangeal ossification in the bones of the distal forelimb. Specifically, the first, second, and third phalanges of the third digit (D3) were evaluated, as well as the third phalanx of digits 1, 2, 4, and 5. All elephants were healthy at the time of examination. A retrospective evaluation of radiographs from six of the 11 juvenile elephants was also completed to augment the data set. This study reports the methods used to obtain high-quality radiographs of the distal juvenile elephant limb, ossification characteristics of the phalanges, relative times of growth plate closure within the proximal phalanges of D3, and a method for age estimation based on radiographic findings. This study will help clinicians in conducting elephant foot radiography, in evaluating foot radiographs in juvenile elephants, in recognizing normal versus pathologic change, and in estimating juvenile elephant age based on radiographic ossification characteristics and growth plate closure times. Consistent use of the proposed foot radiograph technique is recommended to facilitate foot disease recognition and as part of the annual examination of captive Asian elephants.

Idiopathic infertility in two captive male gerenuk (Litocranius walleri walleri).

Two adult male gerenuk (Litocranius walleri walleri) were confirmed infertile with distinctly varying clinical presentations. One animal had unilateral testicular degeneration/hypoplasia, and within 8 mo experienced atrophy/degeneration of the remaining testicle. The second animal had been previously treated with melengesterol acetate (MGA) milled in feed for 1 yr during puberty as part of an aggression-control study. The testes in this individual appeared normal both visually and on palpation; however, repeated semen collection consistently produced ejaculates containing high numbers of immotile spermatozoa, all of a single abnormal morphology: shortened tails, with normal total sperm counts for this species. Both gerenuk had cortisol concentrations within normal ranges for adult male gerenuk. Analysis of serum mineral concentration revealed zinc levels that would be considered low in domestic cattle. Testosterone levels were low for the animal discussed in case 1, but were within normal range for the animal in case 2 compared with other gerenuk. Investigations into endocrine causes, such as abnormal thyroid hormone concentrations and adrenal function, were unrewarding. Both animals discussed in this report are maternally related; therefore, a genetic cause of infertility cannot be ruled out. Further investigation into MGA, as well as the dietary zinc requirements for gerenuk, and resulting effects on spermatogenesis and testicular development are warranted.

Microchip-associated leiomyosarcoma in an Egyptian fruit bat (Rousettus aegyptiacus).

Microchips are commonly used in companion, research, and zoo animal medicine for easy, reliable, and cost-effective identification with relatively low risk of side effects. This report describes development of a metastatic leiomyosarcoma associated with a microchip in an Egyptian fruit bat (Rousettus aegyptiacus).

Mycobacterium asiaticum infection in a red-handed tamarin (Saguinus midas).

A 4-yr-old, intact male red-handed tamarin (Saguinus midas) was evaluated because of a 6-mo history of an enlarging axillary mass. Diagnostic findings included a positive intradermal tuberculin test, persistent severe leukocytosis, and hyperglobulinemia. A nontuberculous mycobacterium species isolated from the mass was identified as Mycobacterium asiaticum using 16s ribosomal DNA sequencing and high-performance liquid chromatography.