Review of spontaneous lesions in the exocrine pancreas of domestic ferrets (Mustela furo).

Large-scale retrospective studies allow for identification of disease trends, such as predisposing factors, typical clinical signs, and range of histologic lesions, which cannot be determined in individual case reports. Lesions of the endocrine pancreas of ferrets are extensively reported; however, there are no in-depth investigations of lesions in the exocrine pancreas. This retrospective analysis presents the histologic features, clinical signs, and concurrent diseases of lesions in the exocrine pancreas of ferrets. Seventy-seven lesions were reported and included acinar cell hyperplasia (n = 32), chronic pancreatitis (n = 16), acute pancreatitis (n = 13), acinar cell adenoma (n = 5), acinar cell carcinoma (n = 4), acinar cell atrophy (n = 3), presumptive acinar cell hypoplasia (n = 2), and lymphoma (n = 2). Our results demonstrate that acinar cell hyperplasia and chronic pancreatitis can both cause grossly visible pancreatic nodules. Hyperplasia was not associated with neoplastic transformation. In addition, acinar cell adenoma was slightly more common than carcinoma, which is contrary to most reports of neoplasia in ferrets. Our findings also suggest that acute pancreatitis can be a sequela to pancreatic biopsy and that there may be an association between chronic pancreatitis and diabetes mellitus in ferrets. Finally, zinc toxicosis was found to be an unlikely cause of pancreatitis in these ferrets based on zinc tissue concentration testing in a subset of cases.

Helicosporidium sp. infection in a California kingsnake (Lampropeltis californiae): Spillover of a pathogen of invertebrates to a vertebrate host.

Helicosporidium is a genus of nonphotosynthetic, green algae in the family Chlorellaceae, closely related to Prototheca. It is a known pathogen of invertebrates, and its occurrence in vertebrates has not been documented. A captive, 10-month-old, male, albino California kingsnake (Lampropeltis californiae) was submitted for necropsy. Gross examination revealed hemorrhagic laryngitis and a red mottled liver. Histologically, intravascular, intramonocytic/macrophagic and extracellular, eukaryotic organisms were observed in all tissues. These organisms stained positive with Grocott-Gomori methenamine silver and periodic acid-Schiff and were variably acid-fast and gram-positive. Ultrastructural analysis revealed approximately 4 µm vegetative multiplication forms and cysts with 3 parallel ovoid cells and a helically coiled filamentous cell. A polymerase chain reaction with primers targeting Prototheca, amplicon sequencing, and Bayesian phylogenetic analysis confirmed it clustered within Helicosporidium sp. with 100% posterior probability. The genus Helicosporidium was found to nest within the genus Prototheca, forming a clade with Prototheca wickerhamii with 80% posterior probability.

Amdoparvovirus-associated disease in red pandas (Ailurus fulgens).

The roster of amdoparvoviruses (APVs) in small carnivores is growing rapidly, but in most cases, the consequences of infection are poorly understood. Red panda amdoparvovirus (RPAV) is highly prevalent in zoo-housed red pandas and has been detected in both healthy and sick animals. Clarifying the clinical impact of RPAV in this endangered species is critical, and zoological collections offer a unique opportunity to examine viral disease association in carefully managed populations. We evaluated the potential impact of RPAV in captive red pandas with a combination of prospective and retrospective analyses. First, we collected feces from 2 healthy animals from one collection over a 6-year period and detected virus in 72/75 total samples, suggesting that RPAV can be a long-term subclinical infection. We next investigated the infections using a retrospective study of infection status and tissue distribution in a cohort of necropsied animals. We performed polymerase chain reaction and in situ hybridization on 43 necropsy cases from 4 zoo collections (3 from the United States, 1 from Europe, 1997-2022). RPAV was present in these populations for at least 2 decades before its discovery and is detectable in common and significant lesions of zoo-housed red pandas, including myocarditis (3/3 cases), nephritis (9/10), and interstitial pneumonia (2/4). RPAV is also detectable in sporadic lesions, including multisystemic pyogranulomatous inflammation, oral/pharyngeal mucosal inflammation, and dermatitis. The colocalization of virus with lesions supports a role in causation, suggesting that despite the apparently persistent and subclinical carriage of most infections, RPAV may have a significant impact in zoo collections.

Bacterial abscesses in whitespotted bamboo sharks (Chiloscyllium plagiosum) in managed care.

Sixteen whitespotted bamboo sharks (Chiloscyllium plagiosum) with histologically similar bacterial abscesses were submitted to Northwest ZooPath from nine zoo and aquarium institutions over a 17-year period. These abscesses were characterized by inflammatory cell infiltrates and necrosis with intralesional small, Gram-positive, acid-fast negative, cocci bacteria. The clinical presentation, histologic findings, and culture results indicate that Enterococcus faecalis is a relatively common cause of these lesions in whitespotted bamboo sharks. This organism also provides a treatment challenge due to its inherent antibiotic-resistant properties and ability to form biofilms, confounding the host's immune response. Enterococcus faecalis represents an important cause for abscess formation and cellulitis in captive whitespotted bamboo sharks.

GASTRIC POLYPOID HYPERPLASIA IN MORAY EELS (MURAENIDAE): EIGHT CASES.

Gastric and intestinal mucosal hyperplasia and polyps are identified as a cause of morbidity and mortality in moray eels. This report describes the clinical presentations, diagnostic procedures, and therapeutic interventions in eight moray eels diagnosed with gastric polypoid hyperplasia. All described cases were humanely euthanized or found deceased, and multifocal adenomatous hyperplasia and polyps extending from the gastric mucosal epithelium were identified in all cases. The moray eels diagnosed with adenomatous hyperplasia and polyps often exhibited anorexia, regurgitation, and occasional changes in buoyancy, and supportive care was unsuccessful in alleviating or resolving these signs.

A REVIEW OF NEOPLASIA IN PROSIMIANS IN HUMAN CARE FROM 1995 TO 2022.

This retrospective study of neoplasia in prosimians in human care reports histologically diagnosed cases from the archives of a nondomestic species pathology service between 1995 and 2022, primarily submitted from zoological institutions. To date, the only prior retrospective study of neoplasia in prosimians, published in 2009, was conducted with cases from a single institution specializing in prosimian noninvasive research and care. In the present study, a total of 153 neoplasms from 109 individuals were identified in the pathology service archives. The most commonly affected species belonged to the Lemuridae (92/109, 84.4%), particularly ring-tailed lemurs (Lemur catta; 55/109, 50.5%), black-and-white ruffed lemurs (Varecia variegata; 19/109, 17.4%), and red ruffed lemurs (Varecia rubra; 14/109, 12.8%). The digestive (49/153, 32.0%), reproductive (35/153, 22.9%), and integumentary (30/153, 19.6%) systems were most commonly affected. Hepatocellular neoplasia was the most common neoplasm overall (35/153, 22.9%), with a large proportion of hepatocellular carcinoma (23/35, 65.7%), suggesting a possible predisposition to this tumor in prosimians. The findings support aggressive behavior of these tumors in prosimians, and a majority (13/23, 56.5%) of cases had evidence of metastasis at the time of submission. Mammary neoplasia was also common (25/153, 16.3%) and predominantly malignant (18/25, 72.0%), in contrast with previous literature, although metastasis was uncommonly reported. The most common integumentary neoplasms were papillomas (12/30, 40.0%), and one report identified squamous cell carcinoma arising directly from a squamous papilloma. Several tumor types are reported herein for the first time in prosimian species, to the authors' knowledge. A literature review identifying additional cases reported since 2009 is also reported. This study contributes a large number of prosimian neoplasia cases to the existing literature to help determine trends in zoological collections and to inform captive prosimian health management.

HEMANGIOSARCOMA IN RED WOLVES (CANIS RUFUS) AND GRAY WOLVES (CANIS LUPUS) IN HUMAN CARE: SIX CASES.

Wolves are commonly housed in zoological institutions and captive breeding facilities that are essential for maintaining genetic diversity and for the recovery of declining populations. Neoplasia is a common cause of mortality in wolves, but hemangiosarcoma has not previously been described. This condition was diagnosed in four red wolves (Canis rufus) and two gray wolves (Canis lupus) housed at five different institutions between 2008 and 2018. Animals were 11-16 yr of age at the time of presentation. Clinical signs included loss of body condition, abdominal distension, lethargy, weakness, ataxia, and hyporexia. Three animals were mildly anemic. All animals were humanely euthanized within an average of 3 d from onset of clinical signs. Two animals had primary splenic tumors, two had pelvic tumors with one originating from the aorta, and one had a cranial mediastinal mass. Diagnosis was made on postmortem histologic examination in all cases. Four wolves had evidence of metastases with foci in the lungs, lymph nodes, mesentery, liver, subcutis/skeletal muscle, kidney, adrenal, and thyroid gland. Hemangiosarcoma should be considered in geriatric wolves presenting with nonspecific signs, particularly if abdominal distension, free peritoneal fluid, or anemia is present.

USE OF HYSTEROSCOPIC MORCELLATION WITH A MYOSURE® DEVICE FOR REMOVAL OF UTERINE FOREIGN MATERIAL IN AN ORANGUTAN (PONGO SP.).

A 36-yr-old female intact hybrid orangutan (Pongo sp.) presented with evidence of chronic bacterial cystitis with no response to treatment with multiple systemic antibiotics. Abnormalities were identified within the reproductive tract on CT scan, and hysteroscopy was pursued based on the recommendation of an obstetrician-gynecologist. Hysteroscopic examination revealed a large amount of intrauterine foreign material consistent with wood wool from the orangutan's bedding. A hysteroscopic morcellator (MyoSure®) was used to remove the foreign material. Histologic examination of endometrial biopsies showed severe suppurative to pyogranulomatous endometritis with intralesional foreign (wood) fibers and bacteria. The orangutan was treated with antibiotics, but evidence of bacterial cystitis persisted. After 15 wk, additional wood wool was identified within the uterus by hysteroscopic examination and was removed similarly. Five months later, there was no recurrence of foreign material on hysteroscopy or CT. This report describes the first documentation of intrauterine foreign material in a nonhuman primate. Hysteroscopic morcellation is a useful technique for noninvasive removal of intrauterine foreign material in great apes.

PRIMARY HEPATIC NEOPLASIA IN THREE ADULT BAMBOO SHARKS (CHILOSCYLLIUM PLAGIOSUM AND CHILOSCYLLIUM PUNCTATUM) IN AN AQUARIUM POPULATION.

Neoplasia in elasmobranchs is uncommonly documented. This report describes primary hepatic neoplasia in three adult female bamboo sharks under managed care: biliary adenocarcinoma in a whitespotted bamboo shark (Case 1; Chiloscyllium plagiosum), biliary adenocarcinoma in a brownbanded bamboo shark (Case 2; Chiloscyllium punctatum), and hepatocellular carcinoma in a whitespotted bamboo shark (Case 3). Case 1 presented with extensive cutaneous papillomas and was electively euthanized. At necropsy, a 4-cm-diameter, pale-tan, firm hepatic mass was identified and diagnosed histologically as a biliary adenocarcinoma. Case 2 presented with decreasing body condition despite normal food intake. Coelomic ultrasound and exploratory surgery revealed several large masses in both hepatic lobes, and the patient was euthanized. At necropsy, nine, 1-6-cm-diameter, black to tan, firm hepatic masses were identified and diagnosed histologically as biliary adenocarcinoma with branchial intravascular neoplastic emboli. Case 3 presented for routine health examination and was euthanized for diagnostic purposes after coelomic ultrasound revealed multiple hepatic masses. At necropsy, two 1-3-cm-diameter, brown- and-black mottled, firm hepatic masses were identified and diagnosed histologically as hepatocellular carcinoma. Immunohistochemistry was performed in two of these cases and was noncontributory, likely because of a lack of cross reactivity between antibodies (antipancytokeratin) and elasmobranch tissues.

BILIARY DUCTAL PLATE MALFORMATION WITH SECONDARY PORTAL HYPERTENSION AND MULTIPLE ACQUIRED SHUNTS IN A LITTER OF AMUR TIGERS (PANTHERA TIGRIS ALTAICA).

Congenital abnormalities in tigers (Panthera tigris) are infrequently reported but have included ectrodactyly, cataracts, and vestibular disease. Primary hepatic disease has been documented in multiple nondomestic felid species but is considered uncommon in tigers. To the authors' knowledge, there are no previous reports of congenital abnormalities of the liver in tigers. In May 2022, two male Amur tiger cubs (Panthera tigris altaica) were born at a zoological institution via cesarean section to address dystocia, following the natural birth of a female cub. Between two and six months of age, all three cubs developed progressive lethargy, inappetence, and neurological signs consistent with hepatic encephalopathy, including obtundation and ataxia. In all three cases, serum biochemical values revealed progressive, marked elevations in hepatic enzyme levels with reduction in hepatic synthetic products (albumin, urea, cholesterol). Computed tomographic imaging showed a large cluster of aberrant tortuous vessels craniomedial to the left kidney in all three tigers, consistent with acquired extrahepatic portosystemic shunts. Histologic examination of the livers identified biliary ductal plate malformations. This report details the presentation, clinical findings, diagnoses, and therapeutic interventions attempted in three Amur tiger cubs with biliary ductal plate malformation and subsequent portal hypertension with multiple acquired portosystemic shunts, an unusual abnormality not previously reported in non-domestic felids.