DILATED CARDIOMYOPATHY IN SLENDER-TAILED MEERKATS (SURICATA SURICATTA) UNDER HUMAN CARE.

Meerkats (Suricata suricatta) housed at two accredited zoological institutions in the United States were evaluated via echocardiography, thoracic radiography, and blood biomarkers-taurine and feline N-terminal pro-B-type natriuretic peptide-to determine the prevalence and severity of dilated cardiomyopathy (DCM) in both populations. In total, 24 meerkats were evaluated and 7 were diagnosed with DCM based on the following parameters: left ventricular internal diameter at end diastole > 1.30 cm, left ventricular internal diameter at end systole > 1.10 cm, and a fractional shortening of <18%. Echocardiographic parameters were identified and reported for normal and affected meerkats, whereas thoracic radiographs were not useful for screening for DCM. Meerkats with DCM were treated with pimobendan and/or benazepril and furosemide if indicated. Seven meerkats died during the study period, with the majority exhibiting myocardial fibrosis. Of the blood parameters tested, elevated taurine levels were associated with DCM. Further research is necessary to characterize the etiology of DCM in meerkats.

PHARMACOKINETICS OF MELOXICAM AFTER SINGLE ORAL AND INTRAMUSCULAR ADMINISTRATION IN CHINA ROCKFISH (SEBASTES NEBULOSUS).

Fish species are important for various purposes including aquaculture stock and display animals, but there are significant gaps in the medical knowledge regarding pharmacological parameters and effective pain management. Meloxicam is a nonsteroidal anti-inflammatory drug (NSAID) that has been studied in few teleost species and with several administration routes. However, these species were typically freshwater or euryhaline fish, and evaluation in marine species is lacking. The pharmacokinetic properties of meloxicam were determined in nine adult China rockfish (Sebastes nebulosus), presumed healthy based on physical examination and benign medical histories. Based on a pilot study, China rockfish were given 1 mg/kg meloxicam via IM injection in the epaxial musculature, and, after a 48-h washout period, 1 mg/kg meloxicam was given by PO gavage. Blood samples were collected from the caudal vein at baseline and at nine time intervals over a 48-h time period following administration of meloxicam. Plasma meloxicam concentrations were determined by reverse phase high-performance liquid chromatography, and noncompartmental analysis was performed. The mean peak plasma concentration after IM injection was 4.9 µg/ml, and the mean terminal half-life was 5.0 h. The mean peak plasma concentration after PO administration was 0.07 µg/ml. Based on these findings, IM injected meloxicam reaches plasma levels consistent with therapeutic concentrations in select mammals, and peak levels were maintained for ≤12 h. Single-dose PO administration failed to achieve similar concentrations, and clinical practicality is unknown. Further studies evaluating NSAID multidose regimes and their pharmacodynamic effects may provide additional dosing information.

RETROSPECTIVE MORTALITY REVIEW OF TUFTED PUFFINS (FRATERCULA CIRRHATA) AT A SINGLE INSTITUTION (1982-2017).

Tufted puffins (Fratercula cirrhata) are commonly exhibited in zoologic institutions across the world, yet there is a paucity of information on causes of mortality in managed populations. This retrospective review reports the pathologic findings associated with 91 tufted puffins at a single institution over 35 years from 1982 to 2017. Common pathologic findings were evaluated by age at death, sex, year, and season. With the exception of neonates, the leading pathologic finding across all age classes was aspergillosis, particularly in adults. Hemoparasitism, predation, and trauma were also frequent causes of mortality. Neonatal mortality was common and primarily caused by omphalitis, yolk sac disease, and bacterial septicemia, with most cultures revealing Escherichia coli. This study also provides documentation of mortality in tufted puffins secondary to avian pox and suspected toxoplasmosis. Understanding morbidity and mortality trends within a population allows institutions to form management plans and implement practices to improve outcomes and survival.

Mortality trends for five species of macropods from a single institution from 1995 to 2016.

Macropods are commonly kept and exhibited species worldwide. Mortality records were reviewed for five species of macropods housed at Cleveland Metroparks Zoo from 1995 to 2016. One hundred sixty-seven deaths occurred including Western grey kangaroo (Macropus fuliginosus) (n = 22), Bennett's wallaby (M. rufogriseus) (n = 64), red kangaroo (M. rufus) (n = 56), wallaroo (M. robustus) (n = 9), and Tammar wallaby (M. eugenii) (n = 16). The leading cause of death was trauma, followed by bronchopneumonia for all species. Gastric dilatation was identified as a concern for red kangaroo. Females lived longer than males across species and were overrepresented by the data set. Oral necrobacillosis and osteomyelitis were health concerns for macropods in this review. Mortality reviews are important as they identifying collection trends and influencing long-term care.

Fatal Meningoencephalitis From a Rhizomucor pusillus Infection in a Juvenile Magellanic Penguin (Spheniscus magellanicus).

A 7-month-old, male Magellanic penguin (Spheniscus magellanicus), housed in an outdoor exhibit, developed acute neurologic signs that progressed to death over 2 days. On gross examination, the bird had congested, edematous lungs, and cerebellar hemorrhage. Histologic examination identified granulomatous pneumonia and encephalitis, with thrombosis and eosinophilic, branching fungal hyphae that had invaded the meningeal vessel walls. Polymerase chain reaction identified the fungus in the brain as Rhizomucor pusillus, an uncommon cause of mucormycosis. This organism has previously been reported in respiratory, skeletal, and sino-orbital lesions of avian species. This clinical report describes meningoencephalitis associated with Rhizomucor pusillus in a penguin.

MORTALITY TRENDS FOR BUDGERIGARS (MELOPSITTACUS UNDULATUS) HOUSED IN A WALK-THROUGH AVIARY IN A ZOO IN NORTH AMERICA, 2009-2019.

Many zoos in North America feature walk-through exhibits that allow members of the public to interact with psittacine species, as these exhibits are popular with guests and can generate additional revenue. There is limited research available on the life expectancy and common causes of mortality of psittacines when group-housed in aviaries. This study compiled data on 496 budgerigar (Melopsittacus undulatus) mortalities at a walk-through aviary at a North American zoo from March 2009 to March 2019, including histopathology on 62 tissue sets collected post mortem, and gross necropsy data for 163 birds deceased from March 2015 to March 2019. The mean age at death or euthanasia of all fledged birds from 2015 to 2019 was 3.57 ± 1.58 yr. The most common causes of death or euthanasia found on gross necropsy were granulomatous disease (39.2%), trauma (16.0%), and Macrorhabdus ornithogaster (13.5%). The most common histologic finding was M. ornithogaster, described as the primary pathologic finding in 31.7% of submitted tissue sets, and recorded as a secondary pathologic finding in 53.2% of submitted tissue sets. Mycobacterial disease was the primary pathologic finding in 25.3% of submitted tissue sets, and was recorded as an additional pathologic finding in 35.4% of submitted tissue sets.

Gastric dilatation and enterotoxemia in ten captive felids.

CASE DESCRIPTION 10 large felids at 8 facilities were determined or suspected to have developed gastric dilatation with or without enterotoxemia over a 20-year period. Four felids were found dead with no premonitory signs. CLINICAL FINDINGS 4 felids (2 male snow leopards [Uncia uncia], 1 male Amur tiger [Panthera tigris altaica], and 1 male Sumatran tiger [Panthera tigris sumatrae]) were found dead or died before they could be evaluated. Six felids had hematemesis (1 male and 1 female African lion [Panthera leo] and 1 male jaguar [Panthera onca]) or abdominal distention and signs of lethargy with or without vomiting (1 male African lion, 1 male Malayan tiger [Panthera tigris jacksoni], and 1 female Sumatran tiger). Gastric dilatation was radiographically and surgically confirmed in the male Malayan and female Sumatran tigers and the jaguar. TREATMENT AND OUTCOME In 3 felids with an antemortem diagnosis, the gastric dilatation resolved with decompressive laparotomy but then recurred in 1 felid, which subsequently died. Three others died at various points during hospitalization. Although Clostridium perfringens type A was recovered from 3 of the 5 felids for which microbial culture was performed, and 2 felids had a recent increase in the amount fed, no single factor was definitively identified that might have incited or contributed to the gastric dilatation. CLINICAL RELEVANCE Gastric dilatation was a life-threatening condition in the large felids of this report, causing sudden death or clinical signs of hematemesis, abdominal distention, or vomiting. Even with rapid diagnosis and surgical decompression, the prognosis was poor. Research is needed into the factors that contribute to this emergent condition in large felids so that preventive measures might be taken.

RETROSPECTIVE MORTALITY REVIEW OF SIX CALLITRICHID SPECIES HOUSED AT A SINGLE INSTITUTION (1990-2014).

Callitrichids are commonly exhibited species in zoological institutions. Retrospective mortality studies allow institutions to evaluate health trends in captive populations and have the potential to advance zoological medicine and husbandry practices. In this single institution, retrospective study, histopathologic records were reviewed for 166 callitrichids comprising six species. For all species and age-groups combined, trauma was the leading cause of death followed by enteritis and stillbirth. In adults and juveniles, the leading cause of death was enteritis, with neonates dying primarily from trauma. Neonatal mortality was high for most species, ranging from 12.5% to 60%, with most neonatal loss in Geoffroy's and pied tamarins. Twin births were commonly associated with neonatal mortality in most species. Intestinal adenocarcinoma was a common finding for adult Geoffroy's tamarin, and hemosiderosis was also identified in this species. Renal disease was a common finding in adult callitrichids and was the second most common cause of death in this age-group. Mortality in the juvenile period (>30 days-1 yr) was uncommon, comprising only 8.4% of the data set. Although capable of surviving into advanced age (>20 yr for one animal), the average age at death for all age classes was 3.84 yr and 9.31 yr for adults. This study contributes to the current knowledge regarding trends in callitrichid health and husbandry and can be used to investigate health trends in this group.

TREATMENT OF MYCOTIC RHINOSINUSITIS IN A BENNETT'S WALLABY ( MACROPUS RUFOGRISEUS) USING TOPICAL VORICONAZOLE SUSPENDED IN A REVERSE THERMODYNAMIC PLURONIC GEL.

An approximately 4-yr-old female Bennett's wallaby ( Macropus rufogriseus) was evaluated for chronic left-sided facial swelling and nasal discharge. Computed tomography, endoscopy, biopsy, mycologic culture, and panfungal polymerase chain reaction were consistent with destructive mycotic rhinosinusitis. The patient's infection was treated with a long-term injectable antibiotic, oral antifungal therapy, and multiple intranasal infusions of voriconazole suspended in a reverse thermodynamic pluronic gel. This case represents the first documented case of mycotic rhinosinusitis in a macropod and underlines the importance of advanced cross-sectional imaging in the diagnosis, monitoring, and management of nasal cavity disease in zoo animals.

SUSPECTED HYPERVITAMINOSIS D IN RED-RUMPED AGOUTI ( DASYPROCTA LEPORINA) RECEIVING A COMMERCIAL RODENT DIET.

An 8 yr, intact male red-rumped agouti ( Dasyprocta leporina) was evaluated for weight loss. Examination revealed poor body condition, hypercalcemia, elevated serum 25-hydroxyvitamin D, metastatic calcification of soft tissues, and hyperechoic kidneys. The diet, formulated for laboratory rodents, contained elevated levels of vitamin D3. Histopathology from a female conspecific that died 5 mo prior identified dystrophic mineralization and nephrosclerosis, suggestive of a vitamin D3 toxicity. The male agouti responded well to a dietary reduction in vitamin D3 and calcium. Six months into therapy, progressive renal failure was identified and was further managed with enalapril, phosphorus binders, and dietary manipulation. Suspected vitamin D3 toxicity has been reported in pacas ( Cuniculus paca) and agouti and has been linked to exposure to New World primate diets. In this brief communication, an agouti developed suspected hypervitaminosis D after receiving a commercial rodent diet commonly fed to this species in captivity.

Ultrasonographic characteristics of the reproductive tract and serum progesterone and estradiol concentrations in captive female red wolves (Canis rufus) with and without reproductive tract disease.

OBJECTIVE To describe ultrasonographic characteristics of the reproductive tract and serum progesterone and estradiol concentrations in captive female red wolves (Canis rufus) with and without reproductive tract disease. DESIGN Prospective study. ANIMALS 13 adult female red wolves. PROCEDURES Wolves with varying parity and history of contraceptive treatment were anesthetized to facilitate ultrasonographic examination and measurement of the reproductive tract and blood collection for determination of serum progesterone and estradiol concentrations in December 2011 and June 2012. Additionally, during the December evaluation, fine-needle aspirate samples of the uterus were obtained for cytologic evaluation. Measurements were compared between wolves with and without reproductive tract disease and between wolves that had and had not received a contraceptive. RESULTS 7 of 13 wolves had or developed reproductive tract disease during the study. Ranges for measurements of reproductive tract structures overlapped between ultrasonographically normal and abnormal tracts, but measurements for abnormal tracts were generally greater than those for normal tracts. The ultrasonographic diagnosis was consistent with the histologic diagnosis for reproductive tracts obtained from wolves that were sterilized, were euthanized, or died during the study. Cytologic results for fine-needle aspirate samples of the uterus and serum progesterone and estradiol concentrations were unable to distinguish wolves with and without reproductive tract disease. Reproductive tract disease was not associated with parity or contraceptive administration. CONCLUSIONS AND CLINICAL RELEVANCE The ultrasonographic images, reproductive tract measurements, and descriptions of reproductive tract lesions provided in this study can be used as diagnostic guidelines for the treatment and management of red wolves with reproductive tract disease.

RETROSPECTIVE EVALUATION OF HISTOPATHOLOGIC FINDINGS IN CAPTIVE GAZELLE SPECIES.

Capturing disease trends among different species has indisputable value to both veterinary clinicians and zoo managers for improving the welfare and management of zoo species. The causes of mortality for eight species of gazelle (addra gazelle, Nanger dama; dorcas gazelle, Gazella dorcas; Grant's gazelle, Nanger granti; sand gazelle, Gazella leptoceros; Saudi goitered gazelle, Gazella subgutturosa; Soemmerring's gazelle, Nanger soemmerringii; Thomson's gazelle, Eudorcas thomsonii; and Speke's gazelle, Gazella spekei) are presented from an 18-yr period (1996 2014). The leading cause of mortality for all species was trauma, followed by bronchopneumonia, and failure to thrive/maternal neglect. Nephritis and rumenitis/abomasitis/enteritis were common ancillary lesions across all species. On average, female gazelle lived twice as long as male gazelle, with an average overall adult survival time of 9.3 yr. Dorcas, Thomson's and addra gazelle females had the longest average survival time (10-13 yr). Calves up to 6 mo of age died most frequently from failure of passive transfer or maternal neglect. Thyroid carcinoma was frequently identified in Thomson's gazelle. Sand and Speke's gazelle frequently died from systemic amyloidosis, and Saudi goitered gazelle were more likely to have renal amyloidosis. Hematuria syndrome was the second most common cause of death in Grant's gazelle. The majority of lesions identified in this study that cause or contribute to mortality are preventable with appropriate management. Knowledge of disease trends in captive gazelle populations can help guide veterinary care, management decisions, and collection management planning.

Duration of immunity in red wolves (Canis rufus) following vaccination with a modified live parvovirus and canine distemper vaccine.

There is growing information available regarding duration of immunity for core vaccines in both domestic and nondomestic species. Vaccination protocols in nondomestic canids have frequently followed guidelines developed for the domestic dog; however, these protocols can be inappropriate for nondomestic canids such as the African wild dog (Lycaon pictus), leaving some animals susceptible to infectious disease and others at risk for contracting vaccine-induced disease. In this study, red wolves (Canis rufus) were vaccinated against canine distemper virus (CDV) and canine parvovirus (CPV) and vaccination titers were followed annually for 3 yr. One hundred percent of wolves developed and maintained a positive titer to CDV for 3 yr and 96.9% of wolves developed and maintained a positive titer to CPV for 3 yr. Seroconversion for canine adenovirus was sporadic. The results of this study support decreasing the frequency of vaccine administration in the red wolf population to a triennial basis.

Iron deficiency anemia in a ring-tailed lemur (Lemur catta) with concurrent chronic renal failure.

CASE DESCRIPTION: A 16-year-old vasectomized male ring-tailed lemur (Lemur catta) with a history of suspected chronic renal failure was evaluated because of extreme lethargy, hyperpnea, and abscess of the right pectoral scent gland. CLINICAL FINDINGS: Examination of the anesthetized patient revealed an impacted right pectoral scent gland with serosanguineous exudate. A CBC and serum biochemical analysis revealed severe anemia, marked azotemia, hyperphosphatemia, and hypocalcemia. TREATMENT AND OUTCOME: Supportive care (including fluid therapy and phosphorus binder administration) was initiated for renal failure; the affected gland was cleaned, and antimicrobials were administered. The patient received 1 blood transfusion, and darbepoetin alfa was administered weekly to stimulate RBC production. Anemia and azotemia persisted. Three months after treatment started, serum iron analysis revealed that iron deficiency was the probable cause for the lack of a consistent regenerative response to darbepoetin injections. Iron dextran injections resulted in a marked regenerative response; however, serum biochemical analysis results after the second injection were consistent with hepatic injury. Hepatic enzyme activities normalized following discontinuation of iron dextran treatment, but the lemur's Hct declined rapidly despite supplementary iron administration PO. The patient developed severe mandibular osteomyelitis and was euthanized because of poor prognosis. Postmortem evaluation of hepatic iron concentration confirmed iron deficiency. CLINICAL RELEVANCE: The family Lemuridae is considered prone to hemosiderosis and hemochromatosis, which delayed rapid diagnosis and treatment of the lemur's disease. Apparent hepatic injury following iron dextran injections further complicated treatment. Findings for this lemur support the use of species-specific total iron binding capacity and total serum iron and ferritin concentrations in evaluation of an animal with suspected iron deficiency.

Hemorrhagic diathesis in avian species following intramuscular administration of polysulfated glycosaminoglycan.

Polysulfated glycosaminoglycans (PSGAGs) have been used for decades in a variety of species for the management of osteoarthritic pain. However, reports on the use of PSGAGs in avian species are scarce. In domestic cats and dogs, PSGAG injections have caused prolongation of clotting times but are considered to be an efficacious drug with a wide margin of safety. This publication documents four cases of fatal coagulopathies in different avian species (one coraciiforme, two raptors, and one psittacine) following the intramuscular administration of PSGAG. All affected birds received varying dosages and dosing intervals of PSGAG. Three of the four birds experienced fatal hemorrhage into the pectoral muscle, while the fourth bled continuously from the injection site. Only one bird had chronic, severe pre-existing disease; the remainder were being managed for osteoarthritis. This report highlights the importance of species-specific dosing of PSGAG and warrants further investigation into the etiopathogenesis of this process.

Medical management of pyometra in three red wolves (Canis rufus).

Pyometra is a serious, life-threatening disease of both domestic and non-domestic species often requiring ovariohysterectomy to preserve the life of the animal. Medical management of pyometra has been successful in domestic and non-domestic species, and the consideration of such treatment is of marked importance in a critically endangered species. Of the canids, the red wolf (Canis rufus) is second only to African hunting dogs (Lycaon pictus) in terms of the prevalence of both cystic endometrial hyperplasia and pyometra. In this report, three red wolves were medically managed for pyometra. Aside from vaginal discharge, none of the wolves exhibited clinical signs, nor were there reflective inflammatory changes in the laboratory findings. All wolves received standard treatment for pyometra, including prostaglandin F2alpha and antibiotic therapy, while one wolf was more aggressively managed with uterine lavage. Pyometra recurred in two of the treated wolves, while the most aggressively managed wolf continues to show ultrasonographic resolution 2 yr posttreatment. Aggressive medical management of pyometra should be considered a treatment option in certain red wolf females, as it may preserve the animal's reproductive potential.

Tick infestation patterns in free ranging African buffalo (Syncercus caffer): Effects of host innate immunity and niche segregation among tick species.

Ticks are of vast importance to livestock health, and contribute to conflicts between wildlife conservation and agricultural interests; but factors driving tick infestation patterns on wild hosts are not well understood. We studied tick infestation patterns on free-ranging African buffalo (Syncercus caffer), asking (i) is there evidence for niche segregation among tick species?; and (ii) how do host characteristics affect variation in tick abundance among hosts? We identified ticks and estimated tick burdens on 134 adult female buffalo from two herds at Kruger National Park, South Africa. To assess niche segregation, we evaluated attachment site preferences and tested for correlations between abundances of different tick species. To investigate which host factors may drive variability in tick abundance, we measured age, body condition, reproductive and immune status in all hosts, and examined their effects on tick burdens. Two tick species were abundant on buffalo, Amblyomma hebraeum and Rhipicephalus evertsi evertsi. A. hebraeum were found primarily in the inguinal and axillary regions; R. e. evertsi attached exclusively in the perianal area. Abundances of A. hebraeum and R. e. evertsi on the host were unrelated. These results suggest spatial niche segregation between A. hebraeum and R. e. evertsi on the buffalo. Buffalo with stronger innate immunity, and younger buffalo, had fewer ticks. Buffalo with low body condition scores, and pregnant buffalo, had higher tick burdens, but these effects varied between the two herds we sampled. This study is one of the first to link ectoparasite abundance patterns and immunity in a free-ranging mammalian host population. Based on independent abundances of A. hebraeum and R. e. evertsi on individual buffalo, we would expect no association between the diseases these ticks transmit. Longitudinal studies linking environmental variability with host immunity are needed to understand tick infestation patterns and the dynamics of tick-borne diseases in wildlife.