Spinal disease in a captive population of Panthera species: Review of 86 cases (2003-2021).

This retrospective study aimed to characterize and determine the prevalence of spinal disease in nondomestic felids within a sanctuary population. A review of 304 postmortem examination reports in Panthera species from 2003 to 2021 revealed that 86/304 (28%) were diagnosed with spinal disease. Spinal lesions were categorized according to pathologic process: degenerative (78/86, 91%), developmental (8/86, 9%), inflammatory (6/86, 7%), or neoplastic (8/86, 9%). Degenerative lesions included intervertebral disk disease (IVDD; 66/78, 85%), spondylosis without concurrent IVDD (4/78, 5%), and idiopathic (noncompressive) degenerative myelopathies (8/78, 10%). Fourteen individuals had lesions in more than 1 category. Developmental cases were vertebral (4/8) or spinal cord (3/8) malformations or both (1/8). Inflammatory lesions included meningitis (4/6) and meningomyelitis (2/6). Neoplasia included vertebral multiple myeloma (4/8) and others (4/8). IVDD often involved multiple disks but primarily affected the cervical (41/66, 62%) and thoracic spine (32/66, 48%). A multivariate binary logistic model predicted the diagnosis of IVDD at postmortem examination, where odds of being affected were highest for males, lions (Panthera leo), and geriatric age group (>14 years). The spinal lesions documented in this study provide insight into high-risk signalment categories and predominant associated lesions affecting captive Panthera populations. Specifically, spinal disease, especially cervical IVDD, is common among Panthera species, and lions, males, and older felids are at increased risk.

FIELD TECHNIQUES FOR VASECTOMY IN BLACK HOWLER MONKEYS (ALOUATTA PIGRA).

Three adult black howler monkeys (Alouatta pigra) were vasectomized for the purpose of population control. Two different surgical approaches (inguinal and pelvic) were used to vasectomize the animals under general anesthesia. One monkey was vasectomized with a pelvic approach, and the other two monkeys were vasectomized with an inguinal approach. The inguinal approach was minimally invasive and proved to be an effective field procedure, utilizing minimal surgical equipment with a mean operative time of 35 min. The inguinal approach allowed for better visualization of the spermatic cord, which prompted easier ligation and transection of the ductus deferens. Identification of the ductus deferens was successfully performed intraoperatively using a tuberculin syringe to aseptically aspirate cord contents, as histopathology was not available. All howler monkeys fully recovered without complication. The social hierarchy of the troop and mating behavior has not been affected. There have been no new pregnancies reported in the troop since the vasectomies were performed. The inguinal approach is preferred as it is minimally invasive and can be performed confidently in a field setting.

EVALUATION OF AGREEMENT BETWEEN OSCILLOMETRIC AND DIRECT BLOOD PRESSURE MEASUREMENTS IN ANESTHETIZED TIGERS (PANTHERA TIGRIS).

Noninvasive blood pressure measurement is commonly performed with oscillometry; however, this technique provides clinically helpful information only if it is representative of the gold standard. Agreement between direct and oscillometric blood pressure measurements were performed in 14 anesthetized, captive tigers (Panthera tigris). A cuff, placed around the tail base and connected to a multiparameter monitor, was used to measure arterial blood pressure oscillometrically and provided systolic, mean, and diastolic pressures. At the same time, direct blood pressures were obtained from a dorsal pedal arterial catheter, and the oscillometric and direct readings were considered paired data points. Agreement between the two methods was evaluated by Bland-Altman plots. All animals completed the study and provided 196 paired data points. The bias (mm Hg) for systolic, mean, and diastolic arterial pressures was -3.7, -0.8, and -1.6, respectively. Limits of agreement (mm Hg) for systolic, mean, and diastolic arterial pressures were -31 to 24, -29 to 27, and -29 to 26, respectively. Oscillometry provided an acceptable amount of readings within 10 and 20 mm Hg of the gold standard. The oscillometric technique provided reasonable agreement with direct measurements. Therefore, in the conditions used in this study, oscillometric blood pressure measured via the ventral coccygeal artery provided reasonable estimates of invasive blood pressure in anesthetized tigers.

MELANOCYTIC NEOPLASIA IN PANTHERA SPECIES: CLINICAL PRESENTATIONS, PATHOLOGIC FINDINGS AND RESPONSES TO TREATMENT.

Neoplasia is a common cause of morbidity and mortality in captive nondomestic felids. Seven tigers (Panthera tigris), two African lions (Panthera leo), and two snow leopards (Panthera uncia) were diagnosed with melanocytic neoplasia (10 malignant melanomas, two benign melanocytomas) over a 20-yr period. Animals were 10-19 yr old and 5/7 tigers were phenotypically white. Malignant melanoma tumor location included skin (n = 4), oral mucosa (n = 2), nasal planum (n = 1), iris/uvea (n = 2), and lip margin (n = 1); melanocytomas were found in skin (n = 2). Metastasis to regional lymph nodes was seen at diagnosis in 3/7 melanoma cases. Thoracic radiography (n = 6) and/or computed tomography (n = 2) did not detect pulmonary metastasis at diagnosis but were useful for detection later in the disease course. Median survival time (MST) for all cases ranged from 1 mon - 40 mon. Seven cases with malignant melanoma underwent treatment, which included surgery, radiation therapy, and administration of the canine melanoma vaccine (Oncept®) or a combination of these treatments; MST was 5-40 mon for these cases. While multimodal therapy may provide an improved survival time, the majority of animals with malignant melanoma invariably died from neoplastic disease. Necropsy confirmed metastasis of malignant melanoma in 7/9 animals; sites included lung, liver, lymph node, kidney, mesentery, pleural cavity, heart, stomach, spleen, and adrenal gland. This case series describes the clinical and histologic findings of melanocytic neoplasia in nondomestic felids as well as multimodal treatment strategies incorporating the canine melanoma vaccine.

ECHOCARDIOGRAPHIC MEASUREMENTS IN ANESTHETIZED CAPTIVE RED PANDAS (AILURUS FULGENS).

A recent review of mortality in captive red pandas (Ailurus fulgens) listed cardiac pathology as the most common cause of death in the adult age group. The aim of this study was to describe the standard echocardiographic variables in 13 captive, healthy, adult red pandas that underwent an elective health examination. In addition, differences between the two subspecies of red panda, A. f. styani than in A. f. fulgens, and association of these echocardiographic variables with age, sex, and body condition score, were examined. Anesthesia was induced and maintained with isoflurane inhalant anesthetic. All animals underwent a full physical examination and comprehensive echocardiogram including 2D, M-mode, and Doppler modes of ultrasound examination. Mean and SD of the echocardiographic variables are reported. Systolic performance was considered subnormal due to the effect of the anesthetic agent. The echocardiographic variables were similar for the two subspecies and sexes, with the exception of the left atrial dimension (2D), which measured larger (P= 0.03) in A. f. styani than in A. f. fulgens, and left ventricular internal diameter in diastole, which measured larger (P = 0.04) in males than females. Several echocardiographic measurements were correlated with age (P < 0.05), whereas the only measurement that significantly correlated with body condition score was end diastolic volume (P = 0.01). These results provide ranges that can offer guidance for predicting cardiac disease in red panda.

INTERVERTEBRAL DISC DISEASE IN THREE LARGE FELIDS (PANTHERA SPP.) TREATED SURGICALLY.

Intervertebral disc disease (IVDD) in captive large felids is a commonly encountered syndrome that is usually treated medically, with surgical cases only sparsely documented in the literature. This case series describes the diagnosis, surgical treatment, and postoperative care of three cases of IVDD in large felids: an 8-yr-old male Bengal tiger (Panthera tigris tigris) with acute paraplegia, a 10-yr-old male tiger of unknown subspecies (Panthera tigris) with progressive tetraparesis, and a 17-yr-old female African lion (Panthera leo) with mild paraparesis. Two cases were diagnosed via magnetic resonance imaging (MRI) and the third was diagnosed with computed tomography myelography. Disc herniations were confirmed during surgery in all cases and via necropsy in two cases. Surgical procedures included a thoracolumbar dorsal hemilaminectomy in one tiger, a cervical hemilaminectomy in the other tiger, and a continuous lumbar dorsal hemilaminectomy in the lion. One tiger was euthanized approximately 1 wk after surgery and the other tiger was euthanized approximately 1 mon after surgery, following a lack of clinical improvement in both cases. The lion, however, improved markedly over several months after surgery before acutely declining secondary to spinal neoplasia. Analysis of these cases suggests that pursuing MRI and surgery as soon as possible after the onset of clinical signs and marking affected disc sites based on imaging to provide landmarks for the surgeon may improve long-term prognosis. Additionally, strict postoperative confinement in an accessible cage is beneficial to facilitate care and prevent overexertion while allowing early movement.

UTILITY OF URINE ANTIGEN TESTING FOR DIAGNOSIS OF BLASTOMYCOSIS IN NONDOMESTIC FELIDS.

Blastomycosis caused by the fungus Blastomyces dermatitidis has been reported to cause disease in numerous species of nondomestic felids. Diagnosis of blastomycosis in domestic species often relies on the combination of clinical signs, radiographic findings, and commercial urinary antigen testing. In this report, the sensitivity, specificity, and positive and negative predictive values for urine blastomyces antigen testing for use in nondomestic felids were examined and compared with findings on postmortem examination. The study showed a sensitivity of 100%, specificity of 91.86%, positive predictive value of 50%, and negative predictive value of 100% for urine antigen testing. Furthermore, radiographic and hematologic findings were compared with those of animals diagnosed with blastomycosis. Radiographic evidence consistent with blastomycosis was found in those animals diagnosed via urine antigen testing, but no significant differences in plasma biochemistry parameters between diseased and nondiseased animals were found. This study provides evidence that a positive blastomycosis antigenuria test result should be combined with other diagnostic methods to confirm the presence of infection with B. dermatitidis, whereas a negative antigenuria test result is 100% effective in predicting the absence of disease.

RABIES DIAGNOSIS AND RESPONSE TO VACCINATION IN SOUTHERN TAMANDUA (TAMANDUA TETRADACTYLA).

Rabies has rarely been described in Xenarthra, and rabies vaccine response has not been documented. A southern tamandua (Tamandua tetradactyla) presented with nonspecific clinical signs and was euthanatized. Subsequently, immunohistochemistry and RT-PCR confirmed a rabies diagnosis. Following these tests, a group of eight captive tamanduas were vaccinated with a killed rabies vaccine, and titers were measured at the time of vaccination and 23 d later. One animal had day 0 titers suggestive of previous vaccination or exposure. All animals had detectable neutralizing rabies virus antibody titers after vaccination, but one animal failed to meet the World Organization for Animal Health's definition for adequate vaccination (≥0.5 IU/ml), and two other animals had low antibody titers (0.56 and 0.6 IU/ml). Rabies should be considered as a possible cause of illness in tamanduas, and rabies vaccination may be a useful preventative measure when anthropic interaction through medical care or ambassador roles is occurring.

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.

SARS-CoV-2 Outbreak among Malayan Tigers and Humans, Tennessee, USA, 2020.

We report an outbreak of severe acute respiratory syndrome coronavirus 2 involving 3 Malayan tigers (Panthera tigris jacksoni) at a zoo in Tennessee, USA. Investigation identified naturally occurring tiger-to-tiger transmission; genetic sequence change occurred with viral passage. We provide epidemiologic, environmental, and genomic sequencing data for animal and human infections.

Translocation of an Anteater (Tamandua tetradactyla) Infected with Rabies from Virginia to Tennessee Resulting in Multiple Human Exposures, 2021.

On August 16, 2021, the Tennessee Department of Health (TDH) was notified of a positive rabies test result from a South American collared anteater (Tamandua tetradactyla) in Washington County, Tennessee. Tamanduas, or lesser anteaters, are a species of anteater in which rabies has not previously been reported. The animal was living at a Tennessee zoo and had been recently translocated from a zoo in Virginia. TDH conducted an investigation to confirm the rabies result, characterize the rabies variant, and ascertain an exposure risk assessment among persons who came into contact with the tamandua. Risk assessments for 22 persons were completed to determine the need for rabies postexposure prophylaxis (rPEP); rPEP was recommended for 13 persons, all of whom agreed to receive it. Using phylogenetic results of the virus isolated from the tamandua and knowledge of rabies epidemiology, public health officials determined that the animal was likely exposed to wild raccoons present at the Virginia zoo. This report describes expansion of the wide mammalian species diversity susceptible to rabies virus infection and summarizes the investigation, highlighting coordination among veterinary and human public health partners and the importance of preexposure rabies vaccination for animal handlers and exotic zoo animals.

Disseminated Mycobacterium genavense infection in a guinea pig (Cavia porcellus): a case report.

BACKGROUND: Mycobacteria are found in many environmental conditions and infect a variety of species, including rodents and rabbits. Guinea pigs are used experimentally as a model for Mycobacterium tuberculosis, but natural mycobacteriosis in guinea pigs has not been reported. CASE PRESENTATION: A 1.5-year-old female guinea pig was found acutely deceased with no premonitory illness. On gross post-mortem examination, multifocal to coalescing, raised, firm, pale tan nodules with discrete, irregular margins were noted over the surfaces of all lung lobes. Histopathology revealed nodules composed of clustered foamy macrophages and multinucleated giant cells containing numerous bacterial rods. Similar bacteria-laden macrophages were noted within sections of the liver, heart, palpebral conjunctiva, duodenum, and cecum. Polymerase chain reaction was performed on tissues collected during post-mortem examination. The 16S rRNA gene product was sequenced and was identical to the Mycobacterium genavense type strain. CONCLUSIONS: To the best of the author's knowledge, this report details the first documented case of Mycobacterium genvaense infection in a guinea pig and a follow up investigation of close-contact animals. Given their experimental susceptibility and this clinical case report, mycobacteriosis should be considered as a differential in guinea pigs exhibiting weight loss in the absence of other clinical signs. With the potential for zoonotic transmission in immunosuppressed individuals, precautions should be taken to safeguard human health in cases of guinea pigs with suspected M. genavense infection.

RETROSPECTIVE REVIEW OF MORBIDITY AND MORTALITY IN A POPULATION OF CAPTIVE BUDGERIGARS (MELOPSITTACUS UNDULATES).

This retrospective study reviews the diseases associated with morbidity and mortality in 221 budgerigars (Melopsittacus undulates) from a captive population from 2013 to 2019. The study aimed to evaluate the health status of a flock of budgerigars typical of today's zoologic collections. Based on previous literature, it was hypothesized that age-related conditions such as neoplasia would be common, whereas metabolic and nutritional disorders would be less common. Neoplasia was widespread among the population, affecting 34% of birds (75/221). Carcinomas made up most neoplastic processes and most commonly affected the renal system (n = 22), followed by the proventriculus (n = 7). Pituitary, adrenal, and hepatocellular carcinomas were less commonly diagnosed. Sarcomas affected the population less often than carcinomas and were found within the coelom (undifferentiated four cases), within the spleen (three cases), within the kidney (two cases), and one subcutaneous soft tissue sarcoma. There were five cases of multicentric lymphoma found most commonly affecting the spleen and liver. Benign neoplasms affected the pituitary most commonly (nine cases), followed by the reproductive system, with seminomas (seven cases) being most common. Macrorhabdus ornithogaster (MO) was found in 56 cases. The majority (38 cases) were found in conjunction with a range of comorbidities, but several birds experienced MO infections alone, and it was thought to have been the cause of death in these birds (22 cases). In contrast to our hypothesis, disease associated with nutritional or metabolic disorders impacted a substantial portion of the population; hepatic lipidosis (26 cases) was the most common along with obesity (26 cases), followed by atherosclerosis, xanthomas, and gout (8, 7, and 4 cases, respectively). Traumatic lesions were noted in 41 cases and were most commonly characterized by head trauma and cerebral hemorrhage. Toxicity was rare; five total cases caused by a single carbon monoxide event were identified.

METHOD COMPARISON FOR MEASUREMENT OF SYMMETRIC DIMETHYLARGININE IN TIGERS (PANTHERA TIGRIS).

Renal disease is well documented in nondomestic felids and is monitored and diagnosed by serum concentration of blood urea nitrogen, creatinine, and phosphorous. Symmetric dimethylarginine (SDMA) has proven to be an earlier and more sensitive biomarker for the assessment of glomerular filtration rate. Although SDMA is commonly measured in nondomestic felids, information concerning the validity of the assay is lacking. The purpose of the study was to perform a method comparison between high-throughput immunoassay and the reference method, liquid chromatography-tandem mass spectrometry (LC-MS/MS), to quantify SDMA concentrations in tiger blood samples. Concentrations of SDMA were measured for 81 individual tiger samples. The SDMA immunoassay demonstrated excellent correlation to the LC-MS/MS reference method. A Passing and Bablok linear regression analysis had a slope of 1.03 (95% CI, 0.99-1.11), an intercept of 1.64 (95% CI, 0.46-2.34), and a Pearson R= 0.99. The mean bias was 1.53 µg/dl (95% CI, 0.63-2.42 µg/dl), and the limit of agreement was ±7.96 µg/dl. The degree of bias is within established acceptance criteria of 1-3 µg/dl for the immunoassay. Although this study provides good evidence of the utility of the immunoassay to measure SDMA in tiger serum and plasma, further assay validation is recommended.

DETECTION OF VECTOR-BORNE INFECTIONS IN LIONS AND TIGERS AT TWO ZOOS IN TENNESSEE AND OKLAHOMA, USA.

Protozoal and bacterial vector-borne infections are frequently diagnosed in domestic felids. However, with the exception of Mycoplasma haemofelis and Cytauxzoon felis, their occurrence in managed nondomestic felids housed in the United States is largely unknown. Following a case in February 2020 of fulminant cytauxzoonosis in an African lion (Panthera leo), EDTA-whole blood samples were collected opportunistically from February 2020 through June 2020 from 34 adult tigers (Panthera tigris) and eight adult African lions from the same sanctuary in eastern Tennessee as well as 14 adult tigers from a zoo in southern Oklahoma. Samples were analyzed for Cytauxzoon felis, Bartonella spp., hemotropic Mycoplasma, Rickettsia spp., Anaplasma spp., Ehrlichia spp., Babesia spp., and Hepatozoon spp. DNA by PCR amplification. All animals were asymptomatic at the time of collection. None of the Oklahoma animals were positive for vector-borne organisms, but these pathogens were detected in tigers at the Tennessee facility, including Cytauxzoon felis (11.8%), "Candidatus Mycoplasma haemominutum" (5.9%), and Ehrlichia ewingii (2.9%). During the study period, two animals developed clinical signs of cytauxzoonosis and were assessed for vector-borne infections as part of their diagnostic evaluation. This study documents the presence of tick-borne diseases in managed nondomestic felids in the southeastern United States and underscores that ectoparasite control measures should be practiced to minimize exposure of carnivores in managed care.

A RETROSPECTIVE STUDY OF BRAIN LESIONS IN CAPTIVE NONDOMESTIC FELIDS.

This retrospective study identified and characterized brain lesions in captive nondomestic felids from a large cat sanctuary. Necropsy reports from January 2002 through December 2018 were examined, and gross images and microscopic slides were reviewed from individual cats, where available. In total, 255 cats met the following inclusion criteria: complete necropsy report available, brain examined grossly or microscopically, and age of >1 mon. Of the 255 cats, 49 cats (19%) were determined to have brain lesions. Eleven different felid species, as well as one captive-bred hybrid (liger), were included in the study, with tigers (Panthera tigris) (55%) and lions (Panthera leo) (18%) being the most common species. Lesions were grouped into six etiologic categories: neoplastic (32%), vascular (26%), inflammatory or infectious (20%), congenital (9%), idiopathic (7%), and metabolic (6%). Not included in these categorized lesions were previously undescribed amphophilic globules in the cerebral cortex of many cats with and without other brain lesions; these were in 95% of lion and 93% of tiger brains where the cerebral cortex was available for histologic examination. These globules were not associated with clinical disease. The histopathologic and gross brain changes documented in this study provide insight into specific diseases and pathologic processes that affect the brains of captive large cat populations.

CANINE DISTEMPER AND PARVOVIRUS VACCINATION WITH RECOMBITEK C3 IN AFRICAN WILD DOGS (LYCAON PICTUS).

Infectious disease threats are increasingly recognized as a major contributor to mortality in wild populations of African wild dog (Lycaon pictus, AWD). Canine distemper virus (CDV) infection has been implicated as a cause of pack mortality in both captive and wild AWD populations. Ten animals were vaccinated with RecombitekTM C3, a vaccine containing a recombinant CDV, and modified live canine parvovirus (CPV) and adenovirus-2 components, at 8, 12, and 16 wk of age. Half of the pups received the vaccine IM and the other half SC. All ten pups had a positive serological response to CDV after the second vaccination, which decreased or stagnated after the third vaccination. Half of the pups had CDV titers ≥32 at 20 wk of age. Titers to CPV were high in all pups prior to vaccination and dropped precipitously over the course of the vaccine series. At the last sampling period, only 50% of the pups had measurable CPV titers. An initially higher titer was seen for CDV in the IM administration group; however, this was not significant at later time points. Vaccination with Recombitek C3 appears to be safe and effected a sustained serological response to CDV in AWD.

ECHOCARDIOGRAPHY AND DIRECT ARTERIAL BLOOD PRESSURE MEASUREMENT IN CAPTIVE CHIMPANZEES (PAN TROGLODYTES) DURING TWO PHASES OF AN ANESTHETIC PROTOCOL.

The effects of α-2 agonists on echocardiographic findings in great apes are not well documented, and knowledge of these effects would expand the understanding of cardiac examinations of chimpanzees under anesthesia with protocols using these drugs. Ten adult chimpanzees (Pan troglodytes), four males and six females, underwent echocardiographic examinations after anesthesia with dexmedetomidine, midazolam, and ketamine (phase 1). Four animals required isoflurane to achieve an adequate plane of anesthesia. Atipamezole was used to antagonize dexmedetomidine, and all remaining animals were placed on isoflurane (phase 2), and then a second echocardiogram was performed. Direct arterial blood pressure was monitored during the anesthetic event. Measurements and recordings were assessed for statistically significant differences between the two phases and sex. There were no significant differences between phases or sex for any two-dimensional echocardiographic measurement of systolic function, although interventricular septum thickness at end systole approached a significant decrease from phase 1 to phase 2 (P = 0.058) when sex was considered a between-subject factor. Left ventricular outflow tract (P = 0.017) and pulmonary artery (P = 0.028) velocities increased after reversal of the dexmedetomidine. Diastolic transmitral flow was consistent with grade 3 diastolic dysfunction (median early to late ventricular filling velocities (E/A) of 2.02, interquartile range [IQR], 1.53-2.13) with a nonsignificant decrease of E velocity and increase in A velocity and decreased E/A after reversal. Trace mitral and tricuspid regurgitation were common findings in the sample population. Arterial blood pressure significantly decreased between phase 1 and phase 2 (P < 0.01). All chimpanzees entered a hypotensive state (mean arterial pressure < 60 mm Hg) during phase 2. Although limited by the small number of chimpanzees, this study showed an increase in afterload, potential diastolic dysfunction, and a decrease in blood pressure after the antagonism of dexmedetomidine. Additional studies to further assess the effects of α-2 agonists in chimpanzees are warranted.

DURATION OF ANTIGEN SHEDDING AND DEVELOPMENT OF ANTIBODY TITERS IN MALAYAN TIGERS (PANTHERA TIGRIS JACKSONI) NATURALLY INFECTED WITH SARS-CoV-2.

Natural infection of three captive Malayan tigers (Panthera tigris jacksoni) with SARS-CoV-2 caused mild to moderate symptoms of lethargy, anorexia, and coughing. Each tiger was longitudinally sampled opportunistically via consciously obtained oral, nasal, and/or fecal samples during and after resolution of clinical signs, until 2 wk of negative results were obtained. Persistent shedding of SARS-CoV-2 genetic material was detected via reverse transcription-polymerase chain reaction in feces up to 29 d after initial onset of clinical signs, but not in nasal or oral samples. Tigers became resistant to behavioral training to obtain nasal samples but tolerated longitudinal oral sampling. Serum was obtained from two tigers, and antibody titers revealed a robust antibody response within 9 d of onset of clinical signs, which was sustained for at least 3 mon. The tigers were infected despite the use of masks and gloves by husbandry personnel. No known cause of the outbreak was identified, despite extensive investigational efforts by the regional health department. No forward cross-species transmission was observed in primates housed in nearby enclosures. The increasing regularity of reports of SARS-CoV-2 infection in nondomestic felids warrants further investigations into shedding and immunity.

EXOCRINE PANCREATIC INSUFFICIENCY-LIKE SYNDROME IN FOUR CAPTIVE TIGERS (PANTHERA TIGRIS).

Exocrine pancreatic insufficiency (EPI) is a condition characterized by a decreased synthesis and secretion of pancreatic enzymes, which results in weight loss, poor hair coat, and diarrhea. The diagnostic test of choice for EPI in domestic cats is feline serum trypsin-like immunoreactivity (fTLI). This paper details four tigers (Panthera tigris) with clinical signs compatible with EPI. On the basis of domestic cat reference ranges, fTLI assays for all four clinically affected tigers were diagnostic for EPI (median 1.0 µg/L; range 0.5-1.2 µg/L). All four tigers had a rapid clinical response to pancreatic enzyme supplementation. Serum from 10 clinically healthy tigers was submitted for the fTLI assay, for comparative purposes. The healthy tigers' fTLI assays were also within range for a diagnosis of EPI in domestic cats (median 3.1 µg/L; range 1.9-4.5 µg/L); however, clinically affected tigers had significantly lower serum fTLI concentrations than healthy tigers (P = 0.0058). Serum cobalamin was below the detection limit in both the affected and healthy tigers (<150 ng/L). Measuring fTLI appears to be a useful tool in the diagnosis of EPI-like syndrome in tigers. As in other species, EPI-like syndrome in tigers may also be associated with cobalamin deficiency.