GLOBAL RETROSPECTIVE REVIEW OF SEVERE ACUTE RESPIRATORY SYNDROME SARS COV-2 INFECTIONS IN NONDOMESTIC FELIDS: MARCH 2020-FEBRUARY 2021.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in nondomestic felids have been documented in North America, South America, Africa, Europe, and Asia. Between March 2020 and February 2021, at nine institutions across three continents, infection was confirmed in 16 tigers (Panthera tigris), 14 lions (Panthera leo), three snow leopards (Panthera uncia), one cougar (Puma concolor), and one Amur leopard cat (Prionailurus bengalensis euptilurus) ranging from 2 to 21 yr old (average, 10 yr). Infection was suspected in an additional 12 tigers, 4 lions, and 9 cougars. Clinical signs (in order of most to least common) included coughing, ocular and/or nasal discharge, wheezing, sneezing, decreased appetite, lethargy, diarrhea, and vomiting. Most felids recovered uneventfully, but one geriatric tiger with comorbidities developed severe dyspnea and neurologic signs necessitating euthanasia. Clinical signs lasted 1-19 d (average, 8 d); one tiger was asymptomatic. Infection was confirmed by various methods, including antigen tests and/or polymerase chain reaction (PCR) of nasal or oral swabs, tracheal wash, and feces, or virus isolation from feces or tracheal wash. Infection status and resolution were determined by testing nasal swabs from awake animals, fecal PCR, and observation of clinical signs. Shedding of fecal viral RNA was significantly longer than duration of clinical signs. Postinfection seropositivity was confirmed by four institutions including 11 felids (5 lions, 6 tigers). In most instances, asymptomatic or presymptomatic keepers were the presumed or confirmed source of infection, although in some instances the infection source remains uncertain. Almost all infections occurred despite using cloth facemasks and disposable gloves when in proximity to the felids and during food preparation. Although transmission may have occurred during momentary lapses in personal protective equipment compliance, it seems probable that cloth masks are insufficient at preventing transmission of SARS-CoV-2 from humans to nondomestic felids. Surgical or higher grade masks may be warranted when working with nondomestic felids.

Protein Electrophoresis and Haptoglobin Values for Captive Bongo (Tragelaphus eurycerus).

Serum samples collected from 37 clinically normal bongo (Tragelaphus eurycerus) and 13 abnormal bongo were tested using assays for acute-phase proteins (APPs) and by protein electrophoresis. Abnormal bongo samples (n = 27) had significantly higher levels of fibrinogen (FIB) (p < 0.001) and trending but not significantly increased haptoglobin (HP) (p = 0.07) vs. samples from normal bongo (n = 37). There were no significant differences in values for total white blood cell counts or for any of the fractions determined by protein electrophoresis. Clinically normal female bongo (n = 19) had significantly lower levels of FIB than normal males (n = 18) (p = 0.014), and this observation was also made with samples from the clinically abnormal group (p = 0.004). Many weak to moderate significant correlations were observed with increasing age, including increased globulins, FIB, and HP and decreased albumin-to-globulin (A/G) ratio and albumin. In clinical cases reviewed in this study, mild HP changes categorized this reactant as a minor APP, which contrasts with the major APP classification of HP in the related species of the cow. The preliminary data indicate that the quantitation of these APPs may offer value in assessing inflammation in this species, but additional studies are needed.

SARS-COV-2 INFECTION AND LONGITUDINAL FECAL SCREENING IN MALAYAN TIGERS (PANTHERA TIGRIS JACKSONI), AMUR TIGERS (PANTHERA TIGRIS ALTAICA ), AND AFRICAN LIONS (PANTHERA LEO KRUGERI) AT THE BRONX ZOO, NEW YORK, USA.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) emerged as the cause of a global pandemic in 2019-2020. In March 2020, New York City became the epicenter in the United States for the pandemic. On 27 March 2020, a Malayan tiger (Panthera tigris jacksoni) at the Bronx Zoo in New York City developed a cough and wheezing with subsequent inappetence. Over the next week, an additional Malayan tiger and two Amur tigers (Panthera tigris altaica) in the same building and three lions (Panthera leo krugeri) in a separate building also became ill. The index case was anesthetized for diagnostic workup. Physical examination and bloodwork results were unremarkable. Thoracic radiography and ultrasonography revealed a bronchial pattern with peribronchial cuffing and mild lung consolidation with alveolar-interstitial syndrome, respectively. SARS-CoV-2 RNA was identified by real-time, reverse transcriptase PCR (rRT-PCR) on oropharyngeal and nasal swabs and tracheal wash fluid. Cytologic examination of tracheal wash fluid revealed necrosis, and viral RNA was detected in necrotic cells by in situ hybridization, confirming virus-associated tissue damage. SARS-CoV-2 was isolated from the tracheal wash fluid of the index case, as well as the feces from one Amur tiger and one lion. Fecal viral RNA shedding was confirmed in all seven clinical cases and an asymptomatic Amur tiger. Respiratory signs abated within 1-5 days for most animals, although they persisted intermittently for 16 days in the index case. Fecal RNA shedding persisted for as long as 35 days beyond cessation of respiratory signs. This case series describes the clinical presentation, diagnostic evaluation, and management of tigers and lions infected with SARS-CoV-2 and describes the duration of viral RNA fecal shedding in these cases. This report documents the first known natural transmission of SARS-CoV-2 from humans to nondomestic felids.

From People to Panthera: Natural SARS-CoV-2 Infection in Tigers and Lions at the Bronx Zoo.

Despite numerous barriers to transmission, zoonoses are the major cause of emerging infectious diseases in humans. Among these, severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and ebolaviruses have killed thousands; the human immunodeficiency virus (HIV) has killed millions. Zoonoses and human-to-animal cross-species transmission are driven by human actions and have important management, conservation, and public health implications. The current SARS-CoV-2 pandemic, which presumably originated from an animal reservoir, has killed more than half a million people around the world and cases continue to rise. In March 2020, New York City was a global epicenter for SARS-CoV-2 infections. During this time, four tigers and three lions at the Bronx Zoo, NY, developed mild, abnormal respiratory signs. We detected SARS-CoV-2 RNA in respiratory secretions and/or feces from all seven animals, live virus in three, and colocalized viral RNA with cellular damage in one. We produced nine whole SARS-CoV-2 genomes from the animals and keepers and identified different SARS-CoV-2 genotypes in the tigers and lions. Epidemiologic and genomic data indicated human-to-tiger transmission. These were the first confirmed cases of natural SARS-CoV-2 animal infections in the United States and the first in nondomestic species in the world. We highlight disease transmission at a nontraditional interface and provide information that contributes to understanding SARS-CoV-2 transmission across species.IMPORTANCE The human-animal-environment interface of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an important aspect of the coronavirus disease 2019 (COVID-19) pandemic that requires robust One Health-based investigations. Despite this, few reports describe natural infections in animals or directly link them to human infections using genomic data. In the present study, we describe the first cases of natural SARS-CoV-2 infection in tigers and lions in the United States and provide epidemiological and genetic evidence for human-to-animal transmission of the virus. Our data show that tigers and lions were infected with different genotypes of SARS-CoV-2, indicating two independent transmission events to the animals. Importantly, infected animals shed infectious virus in respiratory secretions and feces. A better understanding of the susceptibility of animal species to SARS-CoV-2 may help to elucidate transmission mechanisms and identify potential reservoirs and sources of infection that are important in both animal and human health.

Complete Genome Sequence of SARS-CoV-2 in a Tiger from a U.S. Zoological Collection.

This report describes the identification and characterization of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a Malayan tiger in a U.S. zoo.

ANALYSIS OF PLASMODIUM LINEAGES IDENTIFIED IN CAPTIVE PENGUINS (SPHENISCIFORMES SPP.), EIDERS (SOMATERIA SPP.), AND INCA TERNS (LAROSTERNA INCA) IN A NORTH AMERICAN ZOOLOGICAL COLLECTION.

Vector-borne Plasmodium spp. infect a wide range of bird species. Although infections may be asymptomatic, certain genera, especially those that evolved in regions without endemic malaria, appear particularly susceptible to symptomatic disease, leading to morbidity and mortality. High mortalities associated with malaria infections have been documented in captive species of Sphenisciformes, Somateria, and Larosterna, all genera that evolved in climates with low mosquito exposure. To better characterize trends in Plasmodium-related mortality in a zoological collection in New York, necropsy reports for birds of all three genera that died between 1998 and February 2018 were analyzed; comparisons were made between birds that died with or without evidence of malaria infection. A seasonal peak in deaths was observed in birds regardless of their malaria status. There was no significant difference in the age of birds at death between malaria-positive and malaria-negative animals. These results suggest that age and season of death were not associated with malaria status. To investigate an association between parasite lineage and clinical outcome, polymerase chain reaction was used to identify parasite lineage in necropsied birds as well as healthy birds sampled as part of surveillance studies. Twelve different Plasmodium lineages were identified. The relative prevalence of parasite lineages was compared between necropsy and surveillance samples. A single parasite lineage, SGS1 (species: Plasmodium relictum), was significantly more likely to be found in surveillance samples; it was detected in a plurality of surveillance data but found in only one necropsy case. Other parasite lineages were more likely to be found in necropsies than in surveillance samples, most notably SEIAUR01 (species: Plasmodium cathemerium). These data may be consistent with a difference in virulence between parasite lineages. This investigation has implications for the monitoring and care of vulnerable avian species.

RETROSPECTIVE ANALYSIS OF MORTALITY IN CAPTIVE BONGO (TRAGELAPHUS EURYCERUS), 1995-2015.

A retrospective histologic study was performed for 96 deceased bongo (Tragelaphus eurycerus) submitted to Northwest ZooPath from 1995 to 2015. Histologic data were assessed for associations with sex, age, cause of death/euthanasia, and affected organ systems. Female bongo lived significantly longer than males. Males were more likely to die from infectious causes (41.2%), whereas most females died from chronic noninfectious conditions (54.4%) and trauma/stress (28.1%). Of those that died from infectious disease, the respiratory tract was the most commonly affected organ system. The most common infectious agents included acid-fast bacteria and fungi. Chronic conditions included amyloidosis (31.0%), inanition/emaciation (23.8%), and neoplasia (21.4%). Of the 31 animals that died with amyloidosis, 58% appeared to be clinically affected, and amyloidosis was likely an underlying cause of death in 42% of the animals. The most commonly affected organs included the liver, kidneys, adrenal glands, and gastrotintestinal tract. Also noteworthy was a high prevalence of adrenal gland hyperplasia and neoplasia, cystic thyroid glands, and aspiration pneumonia, which were not consistently associated with a prior anesthetic event or other obvious predisposing cause.

ASSESSMENT OF SERUM 25-HYDROXYVITAMIN D CONCENTRATIONS IN TWO COLLECTIONS OF CAPTIVE GORILLAS (GORILLA GORILLA GORILLA).

Serum 25-hydroxyvitamin D concentrations were assessed in subadult to adult captive lowland gorillas ( Gorilla gorilla gorilla) (n = 26) at two institutions with different husbandry and management practices. Serum 25-hydroxyvitamin D (25[OH]D) concentrations for gorillas managed predominantly indoors was low (14.2 ± 5.9 ng/ml), despite consuming commercial biscuits fortified with vitamin D3. Concentrations of 25(OH)D in gorillas with near daily outdoor access were significantly higher than gorillas managed indoors, although many individuals still had serum values below concentrations recommended for adult humans. Consideration should be given to assessing 25(OH)D concentrations in all captive gorillas and providing specific supplementation, particularly to juveniles without access to direct sunlight.

HYPOALDOSTERONISM IN A MATSCHIE'S TREE KANGAROO (DENDROLAGUS MATSCHIEI).

A 20-yr-old female Matschie's tree kangaroo (Dendrolagus matschiei) was diagnosed with hypoaldosteronism, a rare condition in which the body fails to produce normal amounts of the mineralocorticoid aldosterone. Aldosterone plays a key role in body salt homeostasis, increasing sodium reabsorption and promoting excretion of potassium. Hypoaldosteronism resulted in decreased appetite, lethargy, and weight loss in conjunction with hyponatremia, hyperkalemia, and hypercalcemia in this tree kangaroo. The animal was successfully managed with mineralocorticoid replacement using desoxycorticosterone pivalate. To the authors' knowledge this is the first report of hypoaldosteronism in a tree kangaroo and one of the few reports in the veterinary literature in any species.

Diagnosis and Management of Diabetes Mellitus in a Bali Mynah (Leucopsar rothschildi).

An 18-year-old female Bali mynah (Leucopsar rothschildi) was presented for polyphagia, weight loss, and incoordination. Diabetes mellitus was diagnosed based on the history and clinical findings, including persistent hyperglycemia with concurrent hypoinsulinemia and glucosuria. A treatment protocol was developed that led to improvement of clinical signs and management of hyperglycemia over several months. Because of the advanced age of the animal, difficulty in maintaining euglycemia, and the stress of handling and treatment, euthanasia was elected 167 days after initial presentation. At postmortem examination, no pancreatic lesions were detected histologically that would account for the diabetes mellitus. To our knowledge this is the first reported case of diabetes mellitus and clinical management of this condition in a passerine species.

Bilateral intraocular malignant neuroectodermal tumors in a telescope goldfish (Carassius auratus).

Abstract A 5-year-old male telescope goldfish (Carassius auratus) developed buphthalmia of the left eye. An enucleation was performed and a diagnosis of a neuroectodermal tumor was made on histological examination. Although the fish initially recovered, it was killed 49 days postsurgery due to a severe decline in its condition. On histological evaluation of postmortem tissue samples, it was determined that the fish also had a neuroectodermal tumor of the right eye with local invasion of the brain. On immunohistochemistry, the neoplastic cells were positive for S-100. To the authors' knowledge, this is the first published case of naturally occurring bilateral intraocular neuroectodermal tumors in a fish.

Intestinal lymphoma of granular lymphocytes in a fisher (Martes pennanti) and a Eurasian otter (Lutra lutra).

Intestinal lymphoma of granular lymphocytes was diagnosed in a 6-year-old fisher (Martes pennanti) and a geriatric Eurasian otter (Lutra lutra). Clinical signs included lethargy and inappetance in both animals and vomiting and occasional diarrhea in the fisher. The diagnosis in both cases was made using cytology of fresh tissue, histology of fixed tissues, and immunohistochemistry. Granules were seen most clearly on cytologic examination of direct impressions from fresh tissue. Because granules were absent in most histologic sections, cytology of fresh tissue was essential for the diagnosis. Immunohistochemistry determined that the neoplastic cells had positive membranous immunoreactivity to CD3 and were negative for CD79a, which was consistent with alimentary T-cell lymphoma. The disease course in both animals was presumed to be aggressive, with rapid progression of clinical signs, high mitotic index and effacement of local intestinal architecture in both cases, and metastatic disease in the fisher. To the authors' knowledge, this is the first report of lymphoma of granular lymphocytes in a fisher and a Eurasian otter.

Electrocardiography of the Asian elephant (Elephas maximus).

Electrocardiograms (ECGs) are infrequently performed on Asian elephants (Elephas maximus), and few studies have been reported in the literature. The aim of this study was to determine reference ranges of ECG parameters in Asian elephants and to ascertain if age, body weight, and position of the elephant significantly affected the ECG. Electrocardiograms were obtained from 27 captive, nonsedated apparently healthy Asian elephants while they were standing (ST), in right lateral recumbency (RL), and/or in left lateral recumbency (LL). Six-lead ECGs were obtained using novel clamps and long ECG cables (71 cm). From lead I, standard waveforms and intervals were analyzed, including PR interval, QT interval, ST segment, P, QRS, T, and U waves if they were present. One animal was determined to have a previously undiagnosed conduction abnormality and was not included in the study. Most elephants had a sinus arrhythmia in at least one position. With increasing age, there was a trend toward a slower heart rate and significantly longer P waves. Increasing body weight was significantly correlated with longer QT intervals and T waves with lower amplitude. Compared with measurements in ST, LL resulted in P waves and QRS complexes with shorter amplitude, U waves with greater amplitude, PR intervals with shorter duration, and an increased heart rate. Compared with measurements in LL, RL resulted in larger QRS complexes. U waves were most commonly detected in RL and LL. Mean electrical axis calculated in the frontal plane were as follows: standing range -125 to +141 degrees, mean -5 degrees; left lateral range -15 to +104 degrees, mean 27 degrees; right lateral range -16 to +78 degrees, mean 9 degrees. Position-specific reference ranges should be used when interpreting ECGs, and clinicians must be aware of how age and body weight may affect the ECG.

Diagnosis and treatment of Babesia odocoilei in captive reindeer (Rangifer tarandus tarandus) and recognition of three novel host species.

Two captive reindeer (Rangifer tarandus tarandus) at a New York zoological institution were diagnosed with Babesia odocoilei. Clinical signs consistent with acute babesiosis included fever, hemoglobinuria, and hemolytic anemia. Both episodes were precipitated by stressful events that may have compromised their immunocompetence. The diagnosis was confirmed by visualization of intraerythrocytic parasites on stained blood smears, polymerase chain reaction, and speciation of the Babesia by sequencing a hypervariable region of the 18S rRNA gene. One reindeer died with gross and histopathologic lesions, including pigmentary nephrosis with severe acute tubular degeneration and necrosis secondary to intravascular hemolysis. A second reindeer was successfully treated with supportive care and an antiprotozoal, imidocarb dipropionate (Imizol, 12%, Schering-Plough Animal Health, Union, New Jersey 07083, USA) at 3 mg/kg s.c. or i.m. s.i.d. on days 1, 2, 6, 9, and 21. Two other reindeer in the exhibit tested negative for Babesia by polymerase chain reaction but were treated with imidocarb dipropionate as prophylaxis while final testing results were pending. Additionally, B. odocoilei was identified in three novel asymptomatic host species within the collection: yak (Bos grunniens), muntjac (Muntiacus reevesi), and markhor goat (Caprafalconeri). Due to the high morbidity and mortality associated with acute babesiosis, captive reindeer should receive tick prevention, be tested for subclinical infections in endemic areas, and receive aggressive treatment for acute infections when clinical babesiosis is suspected.

Gross and microscopic pathology associated with large cavernous lesions in muscle of Chinook salmon from Lake Ontario.

Since 1999, eight adult Chinook salmon (Onchorhynchus tshawytscha) from Lake Ontario with large, focal, cavernous, fluid-filled muscle lesions have been examined in our respective laboratories. Gross and microscopic examination, cytology, and bacteriology were performed. Microscopically the lesions were consistent with chronic abscesses. Cytologic evaluation revealed diplomonad flagellate Spironucleus within these lesions. We provide a description of the gross and microscopic pathology associated with the cavernous lesions.