Invasive mammary carcinoma in a black-handed spider monkey (Ateles geoffroyi).

Mammary neoplasia is rare in nonhuman primates other than macaques; records in New World primates are exceedingly rare. We report the pathologic and immunohistochemical features of an invasive carcinoma no special type with neuroendocrine differentiation in a captive, black-handed spider monkey (Ateles geoffroyi).

Multicentric cutaneous keratoacanthomas in a free-living marmoset (Callithrix sp.).

Cutaneous neoplasia is common in non-human primates. We describe the gross and microscopic features of multicentric cutaneous keratoacanthomas in a free-living marmoset (Callithrix sp.). Immunohistochemistry for human papillomavirus and herpes simplex virus type I and simplex virus type II was negative. Keratoacanthomas should be included in the differential diagnosis for cutaneous masses in non-human primates.

Spontaneous pulmonary adenosquamous carcinoma in a free-living black capuchin monkey (Sapajus nigritus).

Pulmonary neoplasia is rare among wild New World primates. We report the gross, microscopical, and immunohistochemical features of a primary multicentric pulmonary adenosquamous carcinoma in a free-living black capuchin monkey (Sapajus nigritus). Herein, the spectrum of pulmonary neoplasms in non-human primates is widened and briefly reviewed.

Hepatocellular carcinoma in a free-living marmoset (Callithrix sp.) with concomitant biliary trematodiasis.

Hepatocellular carcinoma (HCC) is rare in New World primates. We report the gross, microscopical, and immunocytochemical features of a spontaneous HCC in a free-living marmoset (Callithrix sp.). Hepatitis B and C virus and aflatoxin immunohistochemistry were negative; however, concomitant intra- and extrahepatic biliary trematodiasis could have played a role.

Rhodococcus equi Infections in Dogs.

Five cases of Rhodococcus equi infection in dogs were identified from 2003 to 2014. Three of the dogs had severe, internal lesions attributable to R. equi that have not been previously described: endophthalmitis, endocarditis, and suppurative pleuropneumonia. Isolates from 4 of the dogs were analyzed by polymerase chain reaction for Rhodococcus virulence-associated plasmid (vap) genes. One isolate was vapA-positive, 2 lacked a virulence plasmid, and 1 carried the novel vapN-associated plasmid (pVAPN) recently characterized in bovine isolates. The pVAPN plasmid has not been described in isolates cultured from companion animals. Four of the dogs either were receiving immunosuppressive drugs or had endocrinopathies. R. equi has the potential to cause significant infections in dogs, and immunocompromised animals should be considered at risk for infection.

Muscle Pathology in Free-Ranging Stranded Cetaceans.

Despite the profound impact that skeletal muscle disorders may pose for the daily activities of wild terrestrial and marine mammals, such conditions have been rarely described in cetaceans. In this study, the authors aimed to determine the nature and prevalence of skeletal muscle lesions in small and large odontocetes and mysticetes ( n = 153) from 19 different species. A macroscopic evaluation of the epaxial muscle mass and a histologic examination of the longissimus dorsi muscle were performed in all cases. The only macroscopically evident change was variable degrees of atrophy of the epaxial muscles ( longissimus dorsi, multifidus, spinalis) in emaciated specimens. The histopathological study revealed single or combined morphological changes in 91.5% of the cases. These changes included the following: degenerative lesions (75.2%), muscle atrophy (37.9%), chronic myopathic changes (25.5%), parasitic infestation (9.2%), and myositis (1.9%). The skeletal muscle is easily sampled during a necropsy and provides essential microscopic information that reflects both local and systemic conditions. Thus, skeletal muscle should be systematically sampled, processed, and examined in all stranded cetaceans.

Coinfection by Streptococcus phocae and cetacean morbillivirus in a short-beaked common dolphin Delphinus delphis.

We describe gross, histopathological, and immunohistochemical features of Streptococcus phocae and cetacean morbillivirus coinfection in a short-beaked common dolphin Delphinus delphis. Major gross findings were cutaneous purulent nodules in the tail fluke, vegetative mitral valve endocarditis, and presumed postpartum pyometra. Histologic examination revealed bacterial septicemia characterized by widespread intravascular coccoid bacterial emboli. These were associated with fibrinonecrotizing to pyogranulomatous dermatitis and panniculitis, embolic pneumonia, neutrophilic and lymphoplasmacytic meningochoroiditis, random neutrophilic hepatitis, lymphoplasmacytic myocarditis and epicarditis, necrotizing adrenalitis, suppurative endometritis, and multicentric reactive lymphadenopathy. Bacteriology and molecular analysis with sequencing of the 16S rRNA gene identified S. phocae from lung, brain, and adrenal gland tissue. Immunohistochemical analysis for morbillivirus detection revealed positive immunolabeling in the epithelium of the choroid plexus of the fourth ventricle. Published reports on S. phocae infection in cetaceans are rare, and pathological details are limited. The present case indicates that S. phocae has potential pathogenic capacity in common dolphins. The pathogenesis is proposed to have involved cutaneous penetration after a skin trauma, leading to initial cutaneous disease and eventual systemic infection.

Verminous Arteritis Due to Crassicauda sp. in Cuvier's Beaked Whales (Ziphius Cavirostris).

The vascular system of Cuvier's beaked whales (CBW) (Ziphius cavirostris; family Ziphiidae), an extremely deep, prolonged-diving cetacean, is increasingly receiving anatomic and physiologic study due to possible anthropogenic interactions; however, vascular pathology rarely has been reported in this species. Thirteen CBW stranded in the Canary Islands from June 2008 to June 2014 were autopsied. A careful dissection of the thoracic and abdominal vasculature was performed on these animals. All had moderate to severe and extensive chronic fibrosing arteritis with aneurysms, hemorrhages, and thrombosis primarily involving the mesenteric and gastroepiploic arteries and the thoracic and abdominal aorta. Microscopically, the lesions varied from subacute subintimal hemorrhages and severe neutrophilic, eosinophilic, and histiocytic dissecting arteritis with intralesional nematode larvae to marked, chronic, fibrosing arteritis with thickening and distortion of the vascular wall with calcification and occasional cartilage metaplasia. In addition, adult nematodes in renal arteries and veins, renal parenchyma and/or ureter were identified morphologically as Crassicauda sp. Nucleic acid sequenced from renal nematodes from 2 animals yielded closest nucleotide identity to C. magna The pathogenesis is proposed to involve a host response to larval migration from the intestine to the kidney through the mesenteric arteries, abdominal aorta, and renal arteries. Severe consequences for such lesions are possible and could vary from reduced vascular compliance to chronic renal disease and predisposition to the development of disseminated intravascular coagulation and multiorgan failure. Severe chronic arteritis in CBW is associated with renal parasitism by Crassicauda spp.

Fatal Erysipelothrix rhusiopathiae septicemia in two Atlantic dolphins (Stenella frontalis and Tursiops truncatus).

We describe gross, histopathologic, ultrastructural, immunohistochemical, and microbiologic features of acute septicemia by Erysipelothrix rhusiopathiae in an Atlantic spotted dolphin Stenella frontalis and an Atlantic bottlenose dolphin Tursiops truncatus. Generalized lymphadenomegaly and widespread hemorrhages were the most consistent macroscopic findings. Tricavitary effusion and icterus were noted in one individual. Histologically, all organs examined showed numerous variably sized bacillary bacterial emboli (Gram-positive; Ziehl-Neelsen-negative), typically associated with systemic congestion, edema, hemorrhages, and fibrinocellular thrombi. These bacteria were frequently intravascular, either extracellular or intramonocytic/macrophagic, and to a lesser extent, free within the interstitium of parenchymal organs. In both cases, microbiological analysis yielded E. rhusiopathiae. A primary anti-E. rhusiopathiae antibody created in mice from one of the strains isolated allowed positive immunohistochemical detection. Electron microscopy and dual immunohistochemistry with lysozyme and MAC387 antibodies confirmed the intramacrophagic location of the bacilli. E. rhusiopathiae, a known multispecies and zoonotic agent, should be considered as a potential etiologic agent in septicemia cases in free-ranging individuals of these dolphin species.

Decompression sickness ('the bends') in sea turtles.

Decompression sickness (DCS), as clinically diagnosed by reversal of symptoms with recompression, has never been reported in aquatic breath-hold diving vertebrates despite the occurrence of tissue gas tensions sufficient for bubble formation and injury in terrestrial animals. Similarly to diving mammals, sea turtles manage gas exchange and decompression through anatomical, physiological, and behavioral adaptations. In the former group, DCS-like lesions have been observed on necropsies following behavioral disturbance such as high-powered acoustic sources (e.g. active sonar) and in bycaught animals. In sea turtles, in spite of abundant literature on diving physiology and bycatch interference, this is the first report of DCS-like symptoms and lesions. We diagnosed a clinico-pathological condition consistent with DCS in 29 gas-embolized loggerhead sea turtles Caretta caretta from a sample of 67. Fifty-nine were recovered alive and 8 had recently died following bycatch in trawls and gillnets of local fisheries from the east coast of Spain. Gas embolization and distribution in vital organs were evaluated through conventional radiography, computed tomography, and ultrasound. Additionally, positive response following repressurization was clinically observed in 2 live affected turtles. Gas embolism was also observed postmortem in carcasses and tissues as described in cetaceans and human divers. Compositional gas analysis of intravascular bubbles was consistent with DCS. Definitive diagnosis of DCS in sea turtles opens a new era for research in sea turtle diving physiology, conservation, and bycatch impact mitigation, as well as for comparative studies in other air-breathing marine vertebrates and human divers.

Mixed testicular neoplasia in a short beaked common dolphin Delphinus delphis.

A diagnosis of mixed testicular neoplasia in a short beaked common dolphin Delphinus delphis involving a Sertoli cell tumor, an interstitial (Leydig) cell tumor and a seminoma is presented. Lymphatic spread of the Sertoli cell tumor to an adjacent retroperitoneal lymph node was observed. Testicular neoplasms have been infrequently reported in marine mammals. Demonstration of clinical signs and further health implications is extremely challenging when dealing with non accessible wildlife species, such as dolphins. However, metastatic potential for these neoplastic conditions should be considered.

Cardiac disease in the Spix Macaw (Cyanopsitta spixii): two cases.

Cardiovascular disease in avian species, other than poultry, is being increasingly reported. In psittacine birds, atherosclerosis and congestive heart failure are the leading cardiovascular diseases, often resulting in multiorgan dysfunction and demise. The Spix's macaw (Cyanopsitta spixii) is arguably the most endangered psittacine species worldwide. We aimed to describe the gross and microscopic findings in two adult Spix's macaws wherein severe cardiovascular pathology resulted in sudden death. Bird 1 had pathologic findings consistent with fibrinoheterophilic vegetative pulmonic valvular endocarditis with luminal obliterative thrombosis, myocarditis and epicarditis, myocardial fibrofatty infiltration and cardiomyocyte loss, as well as generalized septicaemia. Microbiological analysis yielded Pantoea septica from the intestines and Acinetobacter baylyi from the cerebrum. Bird 2 had changes suggestive of right brachiocephalic coarctation-like obliterative arteriopathy. The latter is a novel cardiovascular pathology in avian species, and its severity and extent likely led to acute decompensation of pre-existing cardiac disease. These results add to the body of knowledge on avian cardiovascular pathology and may aid in veterinary medical decisions on caged birds, including those part of ex situ conservation efforts.

Dandy-Walker-Like Malformation in a Free-Ranging Atlantic Harbour Seal Pup (Phoca vitulina concolor).

An 88.5 cm long, 12.9 kg, 3-week-old stranded male Atlantic harbour seal (Phoca vitulina concolor) presented with cerebellar ataxia, delayed postural reactions, hyperaesthesia and nystagmus. The skull was enlarged and domed. Ultrasound through a persistent fontanelle in the frontal bone revealed hydrocephalus. Magnetic resonance imaging showed diffuse enlargement of the ventricular system, an absent cerebellar vermis, hypertrophy of the choroid plexus of the fourth ventricle and enlargement of the caudal fossa. Throughout rehabilitation, the seal failed to achieve milestones critical for successful release or placement in a managed care facility, including the ability to feed independently and haul out. Three months into rehabilitation it began to regurgitate and staff had difficulty administering food to the seal. The seal was euthanized due to a poor prognosis. Post-mortem examination confirmed a) aplasia of the dorsal cerebellar vermis and hypoplasia of the most dorsal portions of the right and left cerebellar hemispheres, b) severe, diffuse, congenital communicating hydrocephalus, and c) aplasia of the interthalamic adhesion and corpus callosum. This case represents the first report of Dandy-Walker-like malformation (DWLM) in a marine mammal and illustrates the importance of advanced imaging and thorough post-mortem examination in free-ranging pinnipeds that strand with evidence of neurological disease.

Trypanosoma cruzi Genotype I and Toxoplasma gondii Co-infection in a Red-Necked Wallaby.

While the health effects of trypanosomes in Australian mammals in their native range are not fully understood, there is evidence of an impact in those species introduced to other geographical regions. Here we report the pathological and molecular features of concurrent fatal trypanosomiasis and toxoplasmosis in an adult female captive red-necked wallaby (syn. Bennett's wallaby; Macropus rufogriseus) from Bee County, Texas, USA. The animal exhibited no clinical signs prior to sudden death. On necropsy, the main findings were generalized organ congestion and bilateral renal petechiation. Microscopically, the main finding was lymphohistiocytic and necrotizing pancarditis with intrasarcoplasmic protozoal pseudocysts containing amastigotes and occasional intrahistiocytic amastigotes, morphologically compatible with Trypanosoma cruzi, as well as rare intrasarcoplasmic protozoal tissue cysts with zoites morphologically compatible with Toxoplasma gondii. Other lesions included acute centrilobular to panlobular necrotizing hepatitis with intrahepatocellular T. gondii cysts, necrotizing splenitis, pulmonary oedema with fibrin, histiocytosis and rare fibrin microthrombi, and acute renal tubular degeneration with proteinosis and pigmented casts suggestive of haemoglobinuria or myoglobinuria. Immunohistochemical labelling confirmed intralesional T. gondii cysts and molecular analyses identified T. cruzi genotype I and T. gondii. This is a unique case that, to the best of our knowledge, represents the first description of T. cruzi and T. gondii co-infection, as well as the first record of naturally occurring infection T. cruzi genotype I infection in macropodids. This case adds to the epidemiological knowledge on Chagas disease in the USA, particularly in Texas where there is a high prevalence of human and canine trypanosomiasis.

Pathological Findings in Leatherback Sea Turtles (Dermochelys coriacea) During an Unusual Mortality Event in São Paulo, Brazil, in 2016.

The leatherback sea turtle (LST; Dermochelys coriacea) is highly migratory and is primarily distributed throughout tropical and subtropical regions. The LST populations found in Brazil are critically endangered. An unusual mortality event occurred between August and November 2016 with 23 LSTs stranded along a 100 km coastal segment in Iguape, Ilha Comprida and Ilha do Cardoso in southern São Paulo state. This study investigated the pathological findings and most likely causes of death of 10 LSTs. Male (n = 9) and adult (n = 9) animals predominated. All but one animal was in good body condition and all were found dead. The most prevalent gross findings were suggestive of bycatch, namely cutaneous erosions, abrasions and/or lacerations around the neck and flippers (n = 9), generalized congestion (n = 8) and pulmonary oedema (n = 6). Other prevalent gross findings were: cutaneous epibiosis by Stomatolepas elegans (n = 7); ileocecal diverticulitis (n = 7); distal oesophagitis (n = 5); and fibrinous coelomitis (n = 5). Microscopically, the most prevalent findings were: hepatic melanomacrophage centre hypertrophy or hyperplasia (n = 9); interstitial pneumonia (n = 8); multisystemic congestion (n = 6); pulmonary oedema with or without aspirated material (n = 5); adrenal coccidiosis (n = 5) with variable multiorgan involvement; and multiorgan bacterial disease (n = 5). Five animals had food ingesta (cnidarians, crustaceans) in the oesophagus or stomach; only one had evident plastic foreign bodies. Asphyxia due to entanglement in nets was the most frequently identified cause of death (n = 8); a cause of death was not identified in two animals. Our findings provide evidence of the severe negative impact of entanglement in fishing nets in LSTs, raising concerns for conservation. These findings also contribute to knowledge of the pathology of LSTs in South American populations.

Facial Squamous Cell Carcinoma and Abdominal Peripheral Nerve Sheath Tumour with Rhabdomyoblastic Differentiation in a Rough-toothed Dolphin (Steno bredanensis).

We report the pathological features of a facial squamous cell carcinoma (SCC) and an abdominal peripheral nerve sheath tumour (PNST) with rhabdomyoblastic differentiation in an aged free-ranging rough-toothed dolphin (Steno bredanensis). The animal was found stranded dead in poor body condition. On external examination, there was a 25 × 7 × 3 cm extensively ulcerated area on the right maxillary region of the rostrum, involving the oral mucocutaneous junction with prominent nodular edges, severe soft tissue loss and extensive maxillary and premaxillary bone lysis. On abdominal dissection, a 5 × 4 × 3.5 cm pale tan to red, raised mass expanded the inner aspect of the right transverse abdominis muscle. Microscopically, the aggressive facial lesion was an acantholytic SCC with extensive osteolysis; there was no evidence of metastasis in the tissues examined. The abdominal mass had cytohistomorphological features compatible with a localized PNST, including whorling, Antoni A and Antoni B areas and Verocay bodies intermixed with rhabdomyoblastic components, as suggested by phosphotungstic acid haematoxylin stain. This neoplasm was locally infiltrative, yet no metastases were observed in the tissues examined. No immunohistochemical investigations could be performed due to lack of tissue availability. Total DNA from the formalin-fixed and paraffin wax-embedded SCC was extracted and tested by polymerase chain reaction for herpesvirus and papillomavirus genetic material. There was no amplification for either of these genera. Other pathological findings observed in this animal were related to the 'live-stranding stress response'. The severity and extent of the facial SCC likely related to anorexia and poor body condition and might have played a role in the stranding and death of this dolphin. These two tumour subtypes add to the relatively uncommon reports of neoplasia in cetaceans. Specifically, these appear to be the first neoplasia records for rough-toothed dolphins, including the first documentation of a PNST with features compatible with rhabdomyoblastic differentiation in a marine mammal.

Pathological Findings in Lowland Tapirs (Tapirus terrestris) Killed by Motor Vehicle Collision in the Brazilian Cerrado.

The lowland tapir (Tapirus terrestris) is the largest land mammal in South America. The species faces steady population decline due to poaching, habitat loss and fragmentation, road-kill, pesticide pollution, competition with domestic livestock and fires, among other threats. The lowland tapir is currently listed as vulnerable to extinction. Little information is available about natural disease processes for the species. This study aimed to report the pathological findings recorded in a cohort of 35 lowland tapirs killed by motor vehicle collision (MVC) on highways of Mato Grosso do Sul State, Brazil, between 2015 and 2018. The main gross pathological findings were those associated with MVC, primarily involving skeletal fractures and internal multiorgan damage with extensive bleeding and/or severe central nervous system injury. The most prevalent concurrent histopathological findings, unrelated to the cause of death, were: adrenal gland degeneration, necrosis and loss of fascicular and reticular cells with replacement fibrosis and cortical atrophy (9/15; 60%); interstitial pneumonia (20/34; 59%); glossitis (9/24; 38%); pulmonary anthracosis (12/34; 35%); colitis (9/28; 32%); and cholangitis/pericholangitis (9/35; 26%). The aetiopathogeneses and clinicopathological significance of some of these findings are unclear; however, parasitic infections appear to be common. Our results highlight the importance of wildlife health information obtained through the study of carcasses of roadkills.

Cerebral and cardiac congenital malformations in neonatal West Indian manatees (Trichechus manatus).

Strandings of live new-born West Indian manatees (WIMs; Trichechus manatus) are one of the main challenges for the conservation of this species in Brazil, particularly in the northeastern states. Congenital malformations (CMs) are rare in sirenians. We identified CMs in two of 19 stranded WIMs that were rescued, rehabilitated and subjected to complete pathological examinations in Ceará and Rio Grande do Norte States between 1992 and 2017. In case 1, dilation of the cerebral lateral and fourth ventricles with abundant cerebrospinal fluid (internal hydrocephalus), was diagnosed. Furthermore, this animal developed necrotizing enterocolitis associated with pneumatosis intestinalis and aspiration pneumonia late during rehabilitation. Cardiac malformations in case 2 included: right ventricle hypoplasia with marked stenosis of the tricuspid outflow, high ventricular septal defect, segmental pulmonary artery aneurysm, mitral valve haemocyst and left ventricular hypertrophy. Herein, we provide the first description of a neural tube defect, specifically a developmental internal hydrocephalus, and multiple cardiac congenital anomalies, together with their respective clinicopathological features in manatees. Although the aetiology of the CMs remains unknown in these cases, a genetic basis is plausible given the low genetic variability in this population. These cases add to the body of knowledge on health and disease aspects of manatees and may provide scientific basis for future medical and conservation efforts on neonatal WIMs.

Histopathological Findings in the Viscera of Malformed Neotropical Viperids.

Congenital malformations (CMs) or developmental abnormalities are pathological processes defined as morphological defects that originate during embryonic stages. A wide variety of CMs is observed in reptiles, most of which are incompatible with normal life. Characterization of CMs and their pathogenesis are of great importance for the conservation of reptiles, including neotropical viperids (NVs). External CMs are often reported in these species, but little is known about concomitant microscopical findings in the viscera of malformed individuals. In order to partially fill in this gap in knowledge, we aimed to investigate and characterize histopathological findings in the viscera of malformed NVs, jararacas (Bothrops jararaca) and South American rattlesnakes (Crotalus durissus), correlating these findings with features of external CMs. From 78 malformed snakes analysed, 100% (19/19) of rattlesnakes and 98.3% (58/59) of jararacas had histopathological changes in the viscera. Liver and/or kidney fatty degeneration was the most common finding in malformed and control animals. Renal glomerulocystic and tubular disease was significantly correlated with brachygnathia (P < 0.05) in jararacas. These results add to the body of knowledge of snake pathology and demonstrate some associations between external CMs and visceral histopathological findings, some of which could have implications for individual survival.

Primary Multicentric Pulmonary Low-grade Fibromyxoid Sarcoma and Chelonid Alphaherpesvirus 5 Detection in a Leatherback Sea Turtle (Dermochelys coriacea).

We describe the gross, microscopical, histochemical and immunohistochemical features of a sclerosing pneumopathic disease process resembling primary multicentric pulmonary low-grade fibromyxoid sarcoma in a juvenile female leatherback sea turtle (Dermochelys coriacea). The animal was fresh, presented in good body condition and stranded dead in Aracaju, Sergipe state, Brazil, in September, 2017. Grossly, the lungs were enlarged bilaterally and the parenchyma was replaced by large, coalescing, white, firm masses that extended into the bronchi and bronchioles and to the pleura. Microscopically, these masses consisted of paucicellular populations of well-differentiated, spindle-shaped fibroblasts with low pleomorphism and low mitotic count, but tissue invasion. Abundant collagen in compact areas merged with peripheral fibromyxoid foci and inflamed stroma. Antibodies specific for cytokeratins AE1/AE3 and smooth muscle actin (SMA) labelled pneumocytes lining the remaining distorted alveoli and the hypertrophied and hyperplastic bronchial muscles, respectively. Tumour cells were negative for SMA; neither neoplastic nor normal tissues cross-reacted with antibodies specific for vimentin or Ki67. Chelonid alphaherpesvirus 5 (ChHV5) polymerase chain reaction analysis from formalin-fixed, paraffin wax-embedded lung tissue sections amplified a 450 base pair fragment of DNA-polymerase (UL30 region) that had 100% homology to sequences previously detected in green sea turtles (Chelonia mydas) on the Brazilian coast. Enterocolitis was a concomitant condition that likely caused morbidity in this case. These findings contribute to the body of knowledge on sea turtle health and expand the known geographical range for ChHV5 in the southern hemisphere.