A 5-yr-old, captive, hatched, female false gharial (Tomistoma schlegelii) presented with a 1-mo history of cervical spinal curvature. Antemortem diagnostics, including blood work, electromyography, muscle biopsies, and advanced imaging tests, were either within reference ranges or did not identify any specific etiology. Necropsy revealed extensive, marked, chronic granulomatous encephalomyelitis along with neuronal necrosis, rarefaction, gliosis, and astrocytosis of the white and gray matter of the cerebrum, cerebellum, brainstem, and spinal cord. Pan-chlamydiae polymerase chain reaction protocols for the 16S ribosomal RNA and ompA genes were performed on samples of spinal cord and brain, and both resulted in amplicons. Sequencing of the products revealed that they were positive for a novel Chlamydia species. Infections by members of the phylum Chlamydiae have been reported in a diverse range of vertebrate hosts, including crocodilians. Chlamydia spp. infections are likely underdiagnosed because of a paucity of diagnostic techniques specific for detection. This is the first case report of a novel Chlamydia species associated with severe granulomatous encephalomyelitis in a false gharial.

Histopathologic differentiation between deep dermal or subcuticular equine sarcoids (ie, nodular sarcoids) and other spindle cell tumors in the dermis and subcutis such as peripheral nerve sheath tumors (PNSTs) can be challenging based on morphologic criteria alone. It has been proposed that polymerase chain reaction (PCR) for bovine papillomavirus (BPV) DNA and S100 immunohistochemistry be used as diagnostic tests to separate equine sarcoids from PNSTs. We reviewed 197 skin-associated spindle cell tumors (ie, soft tissue sarcomas), including PNSTs and sarcoids, received at the University of Florida between 1995 and 2013 and performed BPV PCR and S100 immunohistochemistry on archived paraffin-embedded tissues. We found that BPV DNA was demonstrable in 70% of the sarcoids, 59% of the PNSTs, 37% of the fibrosarcomas, and 22% of other tumors (myxosarcomas, fibromas, and other sarcomas) diagnosed on histomorphologic characteristics. Positive S100 staining was only seen in 12 tumors in the study (5 fibrosarcomas, 3 sarcoids, 2 PNSTs, and 2 other sarcomas). The results demonstrate that BPV is associated with many skin-associated spindle cell soft tissue tumors in horses in addition to sarcoids. S100 was rarely expressed in equine soft tissue sarcomas in the skin but was expressed in many tumor types, including PNSTs and sarcoids. Because 41% of the PNSTs classified by histomorphology in this study were BPV negative and 94% were S100 negative, it is reasonable to classify these as soft tissue sarcomas with nerve sheath tumor histomorphology rather than as either PNSTs or sarcoids.

The Perdido Key beach mouse (Peromyscus polionotus trissyllepsis) is a critically endangered subspecies of the oldfield mouse. The captive population, currently maintained by 3 Florida zoos, is entirely derived from just 3 wild-caught ancestor mice. Necropsy and histopathology revealed chordoma of the vertebral column in 38 of 88 (43%) mice. The tumors were locally expansile and invasive masses of large physaliferous (vacuolated) cells with small, round, hyperchromatic nuclei, similar to the "classic" form of chordomas described in humans. Primary tumors rarely contained small amounts of bone and cartilaginous matrix, characteristic of the "chondroid" form. Neoplastic cells contained abundant granules positive by the periodic acid-Schiff reaction. Brachyury and cytokeratin AE1/AE3 were detected in neoplastic cells by immunohistochemistry, but uncoupling protein 1 was not identified. Primary tumors occurred along the entire vertebral column--cervical, 5 of 38 (13%); thoracic, 16 (42%); lumbar, 13 (34%); and sacral, 10 (26%)--and 10 (26%) mice had multiple primary masses. Metastases to the lungs were noted in 13 of the 38 (34%) mice. Mice diagnosed with chordomas postmortem ranged from 424 to 2170 days old, with a mean of 1399 days. The prevalence of chordoma was not significantly different between males (n = 23 of 50; 46%) and females (n = 15 of 38; 39%).