Pathological lesions of the digestive tract in free-ranging mountain gorillas (Gorilla beringei beringei).

The finding of parasites and bacterial pathogens in mountain gorilla feces and oral lesions in gorilla skeletal remains has not been linked to pathological evidence of morbidity or mortality. In the current study, we conducted a retrospective study of digestive tracts including oral cavity, salivary glands, esophagus, stomach, intestines (gastrointestinal tract [GI]), liver, and pancreas of 60 free-ranging mountain gorillas from Uganda, Rwanda, and the Democratic Republic of Congo that died between 1985 and 2007. We reviewed clinical histories and gross pathology reports and examined histological sections. On histology, enteritis (58.6%), gastritis (37.3%), and colitis (29.3%) were the commonest lesions in the tracts. Enteritis and colitis were generally mild, and judged likely to have been subclinical. Gastritis was often chronic and proliferative or ulcerative, and associated with nematodiasis. A gastro-duodenal malignancy (carcinoid) was present in one animal. A number of incidental lesions were identified throughout the tract and cestodes and nematodes were frequently observed grossly and/or histologically. Pigmentation of teeth and tongue were a common finding, but periodontitis and dental attrition were less common than reported from past studies of skeletal remains. Despite observing numerous GI lesions and parasites in this study of deceased free-living mountain gorillas, we confirmed mortality attributable to gastroenteritis in just 8% (5/60) cases, which is less than that described in captive gorillas. Other deaths attributed to digestive tract lesions included cleft palate in an infant, periodontal disease causing systemic infection in an older adult and gastric cancer. Of all the parasitic infections observed, only hepatic capillariasis and gastric nematodiasis were significantly associated with lesions (hepatitis and gastritis, respectively). Understanding GI lesions in this endangered species is key in the management of morbidity associated with GI ailments.

Pelodera strongyloides infection in Pacific harbor seals (Phoca vitulina richardii) from California.

Skin biopsies were collected from free-ranging harbor seals (Phoca vitulina richardii) from central California (n = 53). Microscopic examination of hematoxylin and eosin-stained tissue sections revealed the presence of tightly coiled nematode larvae within the ostia of numerous hair follicles of four seals. Parasites were characterized by paired lateral alae, platymyarian musculature, and an indistinct, uninucleate digestive tract. Mild chronic superficial dermatitis and perifolliculitis were evident microscopically in association with the intrafollicular parasites. Histomorphologic features of the larvae and their presence within hair follicles are consistent with previous reports of the facultative nematode parasite Pelodera strongyloides. This is the first published report of P. strongyloides infection in any marine mammal. This parasite may be acquired by marine mammals through close contact with soil or decaying organic material and should be considered as a potential differential diagnosis for dermatitis in marine mammals that use terrestrial resting sites.

Disseminated mite infection with ocular involvement in a juvenile bald eagle (Haliaeetus leucocephalus).

A bald eagle (Haliaeetus leucocephalus) was found unable to fly and was admitted to The Raptor Center (TRC). Major clinical signs were thin body condition and a cardiac arrhythmia. Ten days after admission to TRC, ophthalmic examination revealed multiple, distinct serpiginous lesions of chorioretinal atrophy in the ocular fundus of the right eye (OD). The bird was euthanized because of clinical deterioration and poor prognosis. Mites of an undetermined species were found histologically in the retina, episcleral tissues, lungs, and liver at the postmortem examination. Disseminated mite infection should be considered in the differential diagnosis of serpiginous chorioretinal lesions in bald eagles (H. leucocephalus).

Lethal Procyrnea infection in a black-backed woodpecker (Picoides arcticus) from California.

The black-backed woodpecker (Picoides arcticus) is a species of management concern in California. As part of a study of black-backed woodpecker home range size and foraging ecology, nine birds in Lassen National Forest (Shasta and Lassen Counties, California) were radio-tracked during the 2011 breeding season. One of the marked birds was found dead after being tracked for a 10-wk period in which it successfully nested. A postmortem examination of the dead bird revealed that it was emaciated and autolyzed, with the presumptive cause being numerous spiruroid nematodes of the genus Procyrnea in the gizzard. This first observation of Procyrnea nematodes in a black-backed woodpecker is notable because the Procyrnea infection was considered lethal and because Procyrnea has been implicated in substantial die-offs in other bird species, including woodpeckers.

Parasitic encephalitis caused by Stephanurus dentatus in a pig in Brazil.

A pig was in left lateral recumbency with limb spasticity, accentuated prostration, and strabismus, and was euthanized. During autopsy, yellowing of the leptomeninges at the ventral pons to medulla oblongata was noted. In the cerebellar peduncles, there was a focally extensive black-to-yellow area at the level of the vestibular nuclei. Histologic examination revealed a cross-section of a nematode larva, consistent with Stephanurus dentatus, bordered by edema and marked infiltration of mononuclear cells, plasma cells, and a few eosinophils. Vacuolation of the neuropil, with rare gitter cells and axonal spheroids, was also observed. We diagnosed parasitic encephalitis caused by S. dentatus migration based on the pathology findings and characterization of the parasite.

Pathology of Free-Ranging and Captive Brazilian Anteaters.

There is little information on the anatomical pathology of Brazilian anteaters. Considering the relevance of knowledge of diseases of these species for their conservation, the aim of this study was to describe pathological changes in 99 captive and free-ranging anteaters from the Brazilian states of São Paulo, Minas Gerais, Bahia, Mato Grosso do Sul and Amazonas. Forty-two animals were killed on roads and 10 died from burns injuries. Other significant conditions included the metabolic diseases of iron storage disease, tissue mineralization and taurine deficiency, protozoan and metazoan infections, candidiasis, sporotrichosis, clostridiosis and proliferative disorders including squamous cell carcinoma.

Myxozoan parasitism in waterfowl.

Myxozoans are spore-forming, metazoan parasites common in cold-blooded aquatic vertebrates, especially fishes, with alternate life cycle stages developing in invertebrates. We report nine cases of infection in free-flying native and captive exotic ducks (Anseriformes: Anatidae) from locations across the United States and describe the first myxozoan in birds, Myxidium anatidum n. sp. We found developmental stages and mature spores in the bile ducts of a Pekin duck (domesticated Anas platyrhynchos). Spores are lens-shaped in sutural view, slightly sigmoidal in valvular view, with two polar capsules, and each valve cell has 14-16 longitudinal surface ridges. Spore dimensions are 23.1 microm x 10.8 microm x 11.2 microm. Phylogenetic analysis of the ssrRNA gene revealed closest affinity with Myxidium species described from chelonids (tortoises). Our novel finding broadens the definition of the Myxozoa to include birds as hosts and has implications for understanding myxozoan evolution, and mechanisms of geographical and host range extension. The number of infection records indicates this is not an incidental occurrence, and the detection of such widely dispersed cases suggests more myxozoans in birds will be encountered with increased surveillance of these hosts for pathogens.

Filarial dermatitis caused by Filaria taxideae in domestic ferrets (Mustela putorius furo) from the western United States.

Filaria taxideae is a common subcutaneous filarial parasite of American badgers (Taxidea taxus) that has also been reported in skunks in the Western USA. Dermatitis associated with this parasite has been reported in badgers and skunks; however, many individuals have no gross lesions. With the exception of a captive red panda in California, there have been no reports of F. taxidae infection in domestic or exotic/pet animals. In this case series, we document F. taxideae in domestic ferrets from California, Texas, and Colorado and describe the clinical presentation, gross and histologic lesions, and the molecular characterization of this parasite. In two cases, ferrets were positive on Dirofilaria immitis antigen tests but had no evidence of heartworm infection suggesting that F. taxideae antigens can cross-react. These findings indicate that F. taxideae should be considered in cases of dermatitis in ferrets in areas where this parasite may occur.

Use of laser rhinoscopy to treat a nasal obstruction in a captive California sea lion (Zalophus californianus).

Laser rhinoscopy was used to treat a nasal obstruction in a captive California sea lion (Zalophus californianus). The rehabilitated, adult, female sea lion developed mucopurulent, intermittent, bilateral nasal discharge and functional nasal obstruction 20 mo after acquisition by the Aquarium of the Pacific in Long Beach, California. A 3-mm-thick soft tissue structure spanning the region between the soft and hard palates, a deviated nasal septum, and several nasopharyngeal polyps were identified. Biopsies and cultures of the obstructive web showed ulcerative granulation tissue with suppurative inflammation, bacterial infection, and a partial section of an arthropod larva (not speciated). Laser rhinoscopy was performed to relieve the caudal nasopharyngeal obstruction and ablate the polyps. The sea lion appeared to breathe through the nares with lessened nasal discharge for a period of 6 wk after laser therapy, but within 8 wk the mucopurulent nasal discharge returned, the obstruction had reformed, and the sea lion was euthanized. Postmortem examination confirmed antemortem diagnoses of caudal nasopharyngeal obstruction secondary to inflammatory tissue; however, no additional sections of arthropod parasites were located microscopically.

Spirocerca lupi granulomatous pneumonia in two free-ranging maned wolves (Chrysocyon brachyurus) from central Brazil.

The current report describes granulomatous pneumonia due to Spirocerca lupi in 2 free-ranging maned wolves (Chrysocyon brachyurus). Both wolves had multiple, white, 1-1.5 cm in diameter, soft, encapsulated granulomas in the caudal lung lobes, which contained centrally placed parasites on cut sections. Microscopically, there was granulomatous inflammation with numerous intralesional sections of spirurid nematodes. Representative complete adult specimens of nematodes derived from these lesions were submitted for parasitological exam and identified as the spirurid S. lupi. To the authors' knowledge, there have been no published reports of S. lupi in maned wolves.

Cerebral Angiostrongylus cantonensis infection in a captive African pygmy falcon (Polihierax semitorquatus) in southern California.

A 10-month-old, female African pygmy falcon (Polihierax semitorquatus) hatched and housed at the San Diego Zoo developed neurologic signs and died from a cerebral infection with the rat lungworm Angiostrongylus cantonensis. There was an associated mild nonsuppurative meningoencephalitis. This infection was diagnosed on histology and confirmed by detection of species-specific A. cantonensis DNA in formalin-fixed and frozen brain tissue by a polymerase chain reaction assay. To the authors' knowledge, this infection has not previously been reported in a bird in the United States and has not been known to be naturally acquired in any species in this region of the world. The source of the infection was not definitively determined but was possibly feeder geckos (Hemidactylus frenatus) imported from Southeast Asia where the parasite is endemic.

Aspectos anatomopatológicos do parasitismo por nematódeos da superfamília filarioidea em capivaras (hydrochoerus hydrochaeris) de vida livre no Centro-Oeste brasileiro / Anatomic pathology aspects of the parasitism by cruorifilaria tuberocauda in capybaras (hydrochoerus hydrochaeris) in midwestern Brazil

São descritos dois casos de parasitismo por Cruorifilaria tuberocauda em capivaras de vida livre no Distrito Federal, Brasil. Macroscopicamente, observou-se nas superfícies de corte dos rins espessamento acentuado de vasos das regiões cortical e córtico-medular. Microscopicamente, havia arterite proliferativa e granulomatosa acentuada associada a filarídeos intralesionais consistentes com Cruorifilaria tuberocauda. Esse é o primeiro relato do parasitismo por esse filarídeo em capivaras no Distrito Federal.

This report describes two cases of parasitism by Cruorifilaria tuberocauda in wild capybaras (Hydrochoerus hydrochaeris) from Distrito Federal, Brazil. Grossly, there was marked thickening of vessels wall of the cortical and corticomedullary regions of both kidneys. Microscopically, there was severe proliferative and granulomatous arteritis associated with intralesional filarids, consistent with Cruorifilaria tuberocauda. For the first time this filarid is reported parasitizing capybaras in Distrito Federal, Brazil.

Renal infection by a new coccidian genus in big brown bats (Eptesicus fuscus).

A novel coccidian parasite from the kidney of big brown bats (Eptesicus fuscus) is described. This coccidian (Nephroisospora eptesici nov. gen., n. sp.) was associated with a generally mild, focal or multifocal, well-demarcated cortical renal lesion less than 1 mm in diameter. The lesion represented cystic, dilated tubules with hypertrophied tubular epithelial cells and was present in the kidneys of 29 of 590 bats. Numerous coccidian parasites in various stages of development were present within the tubular epithelial cells and within the cyst lumina. Oocysts were collected from cystic dilated tubules. Thin-walled, sporulated ellipsoidal oocysts measuring an average of 18.9 x 20.8 microm were present in kidney tissue. The oocysts contained 2 sporocysts with 4 sporozoites. A polar body and a prominent oocyst residuum were present in the oocysts, but no micropyle, sporocyst residuum, or Stieda bodies were detected. Analysis of the 18S rRNA gene sequence put the parasite in the Sarcocystidae. The parasite is closely related to Besnoitia, Hammondia, Neospora, and Toxoplasma. Ultrastructural features, such as the presence of an apical complex in merozoites, support the identification of a coccidian. A new genus and species, Nephroisospora eptesicii, is proposed for this unusual coccidian in which the entire cycle is completed in the kidney of a single host; it has a membrane-like oocyst wall, sporogony occurs in the host rather than in the abiotic environment, and the positioning of the parasite by nucleic acid sequence indicates it to be closely allied to Sarcocystis and Besnoitia.