Comparative study of non-suppurative meningoencephalitis in cattle in Southern Brazil.

Viral neurologic diseases are common in cattle, although most non-suppurative meningoencephalitis (NSM) remains etiologically unknown. We compared the epidemiological, clinical, and pathological data among 79 cases of rabies, 12 cases of NSM of unknown etiology (NSM-UE), and 8 cases of herpetic meningoencephalitis previously diagnosed in cattle in Southern Brazil. Neurological clinical signs were similar among rabies and NSM-UE and different in cattle with herpetic meningoencephalitis. Only two herpetic meningoencephalitis cases had gross lesions in the central nervous system, characterized by malacia and hemorrhage. Histologically, all three groups had mild to severe multifocal infiltrates of lymphocytes, plasma cells, and macrophages/microglial cells in the Virchow-Robin space, neuropil, and leptomeninges, and gliosis. Other findings included malacia and eosinophilic intracytoplasmic inclusion in rabies, and malacia and intranuclear amphophilic inclusion in herpetic meningoencephalitis. By immunohistochemistry, the predominant inflammatory cells in all cases were T lymphocytes, followed by macrophages/microglial cells, B lymphocytes, and astrocytes. The T lymphocyte count showed statistically significant differences between the diseases. Our results revealed few differences between the groups. Although the etiological agent involved has not been identified in cases of NSM-UE, the characteristics observed in this study showed similarity with viral diseases.

Complex neural tube and skeletal malformations, resembling Chiari malformations, in two calves.

Two 1-day-old full-term female calves from different farms located in the Brazilian state of Rio Grande do Sul were unable to stand due to paresis of the pelvic limbs. Both calves had spina bifida on the spinal lumbar segment and were submitted to euthanasia due to poor prognosis. Postmortem examination revealed cerebellar herniation, caudal displacement of the brainstem, rostral deviation of the cranial nerves, caudal extension of occipital lobes, absence of dorsal lamina of lumbar vertebrae with exposed spinal cord, myelodysplasia, kyphosis, segmental spinal agenesis, renal fusion, muscular atrophy, and arthrogryposis. Histology highlighted myelodysplasia (syringomyelia and diplomyelia) and muscular atrophy. The reverse transcription-polymerase chain reactions for ruminant pestivirus were negative. Based on these lesions, the diagnosis of complex neural tube and skeletal malformations was made. A review of previous publications on calves diagnosed with these malformations, originally called Chiari or Arnold-Chiari malformations, revealed a wide range of nervous system and skeletal lesions. These variations amplified the uncertainty regarding whether all cases represent the same disorder and reinforced the importance of reconfiguring the terminology.

Parasitic Granulomatous Dermatitis Caused by Pelodera spp. in Buffalo on Marajó Island, Pará.

This is the first report of parasitic granulomatous dermatitis caused by Pelodera spp. in a buffalo. The affected buffalo was about seven years old, was a female of the Murrah breed and belonged to a property located on Marajó Island in the State of Pará. During the clinical examination, the animal was in a standing position and presented several multifocal nodular and placoid masses throughout the body, mostly on the forelimbs, hindlimbs, abdomen, mammary glands, perineum, vulva and tail. These masses were also observed on the nasal mucosa, head, neck, back and chest. On macroscopic examination, the skin had several multifocal-to-coalescent sessile nodular and placoid lesions. Histopathology of the skin showed a marked reduction in the number of hair follicles. In the superficial dermis, there was significant multifocal-to-coalescent inflammatory infiltration, consisting of macrophages, epithelioid macrophages, lymphocytes, plasma cells and multinucleated giant cells. In the remaining hair follicles, there were numerous cross and longitudinal sections of small rhabditoid nematodes characterized by a thin cuticle, platymyarian musculature, an intestinal tract, a rhabditiform esophagus and lateral alae (morphologically compatible with Pelodera spp.). The diagnosis of parasitic dermatitis was confirmed by histopathological skin lesions associated with the presence of intralesional rhabditiform larvae morphologically compatible with Pelodera spp.

Psoralges libertus mite infestation in Tamandua tetradactyla: a 127-year gap in the literature due to scarcity of reports.

This study addresses the report of Psoralges libertus mite infestations in Southern Tamandua (Tamandua tetradactyla) after a 127-year gap in the literature, detailing clinical conditions, histopathological findings, and mite identification via morphology. The research broadens our understanding of mite habitats, highlighting challenges in managing parasitic health in free-ranging and captive animals. It underscores the importance of ongoing surveillance for conservation and public health, including potential zoonotic concerns. A P. libertus report in T. tetradactyla after over a century highlights the scarcity of publications on mite-induced mange in this mammalian species. Investigating potential P. libertus' impacts on tamanduas' well-being necessitates further research, particularly regarding pathogenicity, agent epidemiology, and host interaction. This study enhances our comprehension of parasite-host interactions and their relevance to wildlife conservation.

Monensin poisoning outbreak in free-ranging and captive birds.

Monensin poisoning is uncommon and has been rarely reported in birds. This work aimed to described clinical-pathological aspects of an outbreak of monensin poisoning in captive and free-ranging birds. Thirty-seven of 600 captive birds fed a diet containing 893.19 mg/kg of monensin died within 10 days (mortality 6.17%). There was no ionophore antibiotics on the feed label supplied to captive birds, which established an error in feed production. Necropsies were performed on twelve animals: Muscovy duck (Cairina moschata) (2/12), greater rhea (Rhea americana) (2/12), black-necked swan (Cygnus melancoryphus) (2/12), garganey (Anas querquedula) (1/12), ostrich (Struthio camelus) (1/12), and common pigeon (Columbus livia) (4/12). These four common pigeons were free-ranging birds and died after eating the same contaminated feed. Birds were mainly found dead, however in animals which clinical signs were observed (Columba livia, Rhea americana, Cairina moschata, Anas querquedula, and Struthio camelus), they included incoordination, inability to stand, and intense prostration, that ranged from 24 to 72 h until death. Grossly, five birds had focally extensive pale firm areas in the myocardium and two had in the skeletal muscles, one being concomitant lesions. Histologically, muscle necrosis and degeneration were observed in striated musculature (skeletal and/or heart) in all birds analyzed. Monensin poisoning outbreaks can affect free-ranging birds that are fed on external feeders, as well as captive birds, due to an error in the feed formulation.

Histological and immunohistochemical features of carcinomas with pulmonary involvement in cattle.

Primary pulmonary neoplasms in cattle are rare. There are few studies on the pathological findings of these neoplasms in this species. This study aimed to describe the histological and immunohistochemical findings of primary and metastatic pulmonary carcinomas in cattle. We conducted a retrospective study of 19 cases of epithelial neoplasms with pulmonary involvement. Histologically, most of the neoplasms were classified as primary pulmonary neoplasms, including different adenocarcinoma subtypes (4/19, 21%) and adenosquamous carcinomas (3/19, 16%), followed by squamous cell carcinoma (6/19, 32%), metastatic uterine adenocarcinoma (4/19, 21%), metastatic hepatocellular carcinoma (1/19, 5%), and metastatic cholangiocarcinoma (1/19, 5%). By immunohistochemistry, all neoplasms were positive for pancytokeratin, and 4/19 (21%) were positive for vimentin. Primary pulmonary neoplasms had immunoreactivity for thyroid transcription factor-1 (6/7), while only 2 of these cases were positive for napsin A. All cases with squamous differentiation (9/9) had immunoreactivity for cytokeratin (CK) 5/6, while only 7 of these cases were positive for p40. CK20, CK7, and CK8/18 showed varied immunoreactivity in the primary and metastatic pulmonary carcinomas but were important markers to confirm the diagnosis of primary mucinous adenocarcinoma and metastatic cholangiocarcinoma. HepPar-1 was only positive in the metastatic hepatocellular carcinoma. The limited number of cases of metastatic uterine adenocarcinomas in this study precluded identification of a specific immunophenotype for this tumor. Immunohistochemistry proved to be an important tool to confirm the proper classification of these neoplasms.

Spontaneous orbitofacial neurofibroma in a sow / Neurofibroma orbitofacial espontâneo em uma matriz suína

Neurofibromas are neoplasms derived from nerve bundles and are frequent in humans but not common in animals. This report described the macroscopic, histologic, and immunohistochemistry findings of an orbitofacial neurofibroma in a sow. The sow presented left eyelids with marked expansion, associated with severe ectropion and reddening of both conjunctival mucosae. The mass on the cutting surface was homogeneous, with a light tan, and shiny, measuring 9.0 x 7.0 x 7.0 cm in width, compressing the eyeball. Microscopically, there was paucicellular neoplastic proliferation of elongated cells amid the accentuated myxoid matrix. There were multifocal areas where well-differentiated nervous fascicles and skeletal musculature were seen. Neoplastic cells were immunostained positive for GFAP, neurofilament, S-100, Sox-10, and vimentin. Cytokeratin showed immunolabeling around primitive nerve bundles and desmin around neoformed vessels and muscle bundles within the tumor. Orbitopalpebral and orbitofacial neurofibroma, despite being common in humans, have not been described in domestic pigs and should be considered as a differential diagnosis in eyelid tumors in pigs.

Neurofibromas são neoplasias derivadas dos feixes nervosos e são frequentes em humanos, mas incomuns em espécies animais domésticos. Esse relato tem como objetivo descrever os achados macroscópicos, histológicos e imuno-histoquímicos de um neurofibroma orbitofacial em uma matriz suína. O animal apresentava as pálpebras esquerdas acentuadamente expandidas, associada a severo ectrópio e avermelhamento de ambas as mucosas conjuntivais. A tumoração palpebral, na superfície de corte, era homogênea, levemente acastanhada e brilhante, medindo 9,0 x 7,0 x 7,0 cm, e comprimia o globo ocular. Microscopicamente foi observada uma proliferação neoplásica pobremente celular de células alongadas no meio de uma acentuada quantidade de matriz mixoide. Havia áreas intratumorias multifocais onde fascículos nervosos bem diferenciados e musculatura esquelética foram observados. As células neoplásicas foram positivas na imuno-histoquímica para GFAP, neurofilamento, S-100, Sox-10 e vimentina. Citoqueratina mostrou uma imunomarcação ao redor de feixes nervosos primitivos e desmina ao redor de vasos neoformados e feixes musculares dentro do tumor. O neurofibroma orbitofacial, apesar de comum em humanos, nunca foi descrito em suínos domésticos e deve ser considerado um diagnóstico diferencial para neoplasias palpebrais em suínos.

Pathological findings associated with Dipetalonema spp. (Spirurida, Onchocercidae) infection in two species of Neotropical monkeys from Brazil.

Among vector-borne helminths, filarioids of the genus Dipetalonema (Spirurida: Onchocercidae) localize in several tissues and body cavities of several animal species, causing mild to moderate lesions. The pathological findings associated with Dipetalonema spp. infection in Neotropical monkeys from southern Brazil are herein described, along with a fatal case due to filarial polyserositis and entrapment of an intestinal segment. At necropsy, nematodes were observed in abdominal and thoracic cavities, or in the pericardium of 37 (31.3%) out of the 118 individuals examined (i.e., 35 Alouatta guariba clamitans and two Sapajus nigritus). In addition, at histology, 27.0% of positive animals presented microfilarie (inside blood vessels of lung, spleen, liver, and brain) and 8.1% presented adult nematodes in the heart, lung, and liver. In two cases, cross-sections of filarioids were associated with areas of epicardial thickening with intense fibrosis and pyogranulomatous inflammation in the brain, heart, liver, lungs, or spleen. The DNA fragment was amplify using the cox1 gene, sequenced and analyzed to identify the nematode species collected; presence of Wolbachia was assessed in the filarioids using the 16S rRNA gene. At BLAST analysis of the cox1 gene, 10 sequences showed 91.7% nucleotide identity with Dipetalonema gracile, and two with D. gracile (98.5%) and Dipetalonema graciliformis (98.3%). Phylogenetic analyses clustered sequences of the cox1 obtained in this study in two clades corresponding with the host species. Wolbachia sp. endosymbiont was detected in four samples. Data herein reported provide a description of pathological lesions associated with the infection by Dipetalonema spp., suggesting that they may cause disease in Neotropical monkeys. In addition, a better understanding of diversity and biology of Dipetalonema spp. in South America is needed to assess the impact they may cause in native non-human primates from Brazil.

Acute necrotic hepatotoxicity caused by Melanthera latifolia (Asteraceae) in cattle.

This study aims to report a spontaneous and experimental intoxication in cattle by Melanthera latifolia (Asteraceae) for the first time, and to describe its epidemiological, clinical, and pathological findings. An outbreak of acute toxic hepatopathy in cattle occurred from December of 2021 to January of 2022 in a beef cattle farm from Rio Grande do Sul state, Southern Brazil, and resulted in 94 deaths from a herd of 430 animals. At necropsy, lesions consisted of enhanced lobular pattern of the liver, transmural gallbladder edema, and hemorrhages on the surface of multiple organs. The main microscopic lesion was marked hepatocellular necrosis in the centrilobular region associated with hemorrhage and infiltration of neutrophils. During the outbreak, multiple specimens of M. latifolia were noted in the paddocks where affected cattle were grazing and many showed signs of consumption. No other known acute hepatotoxic plants were found. Two 12-month-old steers were experimentally intoxicated with a single oral dose of the fresh plant (flowers, leaves, and less fibrous stalks). One bovine ingested a dose of 10 g/kg and was euthanized after 48 h, and the other ingested 15 g/kg and was euthanized 17 h later. Clinical signs, macroscopic, and microscopic lesions in both animals were similar to those observed in the spontaneous cases. Thus, this study demonstrates that M. latifolia was the cause of the outbreak of acute toxic hepatopathy with significant mortality in cattle. M. latifolia nor any plant of the genus Melantherahad ever been reported as toxic.

Streptococcus canis prostatitis and endocarditis with thromboembolism in a dog with sertoli cell tumour in a cryptic testis and prostatic squamous metaplasia.

We describe an unusual case of prostatitis caused by Streptococcus canis evolving to endocarditis and splenic, renal, and cerebral thromboembolism in a dog, associated with a Sertoli cell tumour in a cryptic testis and diffuse prostatic squamous metaplasia. A nine-year-old, intact male, mixed-breed dog was presented to a veterinary teaching hospital with abdominal pain and prostration. Physical examination and abdominal ultrasonography revealed an atrophic right testicle located in the subcutaneous tissue. The left testicle was in the abdominal cavity with increased dimensions and irregular contours. Complete blood count analysis showed marked neutrophilic leukocytosis and thrombocytopenia. After clinical worsening, euthanasia was performed, and the dog was submitted to post-mortem examination. The main gross findings included testicular malposition with one cryptic and one ectopic testis, enlarged prostate with purulent content, distension of the urinary bladder with cloudy urine, vegetative valvular endocarditis in the mitral valve, and spleen and renal infarcts. Histological examination showed a Sertoli cell tumour in the abdominal testis, diffuse prostatic squamous metaplasia with marked keratinization associated with bacterial prostatitis, fibrinonecrotic cystitis, bacterial endocarditis with marked myxomatous degeneration in the mitral valve, and splenic, renal, and cerebral thromboembolism. Microbiological analysis identified Streptococcus canis in the prostate and mitral valve. Sertoli cell tumour of cryptic testis increases oestrogen production and leads to squamous metaplasia of the prostate, which should be considered as predisposing factors for ascending S. canis infection from the urogenital tract to the prostate. Then, haematogenous spread of S. canis from the prostate to mitral valve cause endocarditis and subsequent thromboembolism and infarcts, all decisive to poor prognosis in this case.

Emergence of Mansonella sp. in free-ranging primates in southern Brazil.

Mansonellosis is a neglected and emerging tropical disease. Among all zoonotic filarial diseases, it is probably the most prevalent and least studied, with approximately 114 million people infected. The parasites of Mansonella spp. are among the most common blood parasitemias and are widely found in Africa and Latin America. Through molecular analysis of blood samples from free-ranging primates Sapajus nigritus (n 33) and Alouatta guariba clamitans (n 5) in the southern states of Brazil (Santa Catarina and Rio Grande do Sul), we identified samples positive for Mansonella perstans in two specimens of A. guariba clamitans. A fragment of 578 bp from the ITS intergenic region (5.8S-ITS2-28S) was targeted for an initial PCR screening. Subsequently, positive samples were subjected to other PCR assays targeting a fragment of the 12S and the 18S genes. This is the first record of molecular detection of the agent in this host in the Pampa Biome. With a wide distribution across Brazil and Argentina, these primates may represent a potential wild reservoir for the zoonotic agent of mansonellosis. Entomological and transmission studies are essential to avoid the urbanization of mansonellosis and to understand the cycles of agents in different environmental scenarios.

Clinical and pathological aspects of progressive hyperphosphatasemia associated with vacuolar hepatopathy and hepatocellular carcinoma in a Scottish Terrier bitch / Aspectos clínicos e patológicos da hiperfosfatasemia progressiva associada à hepatopatia vacuolar e carcinoma hepatocelular em uma cadela da raça Scottish Terrier

Hyperphosphatasemia refers to an increase in alkaline phosphatase serum activity, and Scottish Terriers (STs) are predisposed to develop this condition of uncertain pathogenesis. This study describes a case of progressive hyperphosphatasemia with vacuolar hepatopathy and hepatocellular carcinoma (HCC) in a ST bitch. This dog had a five-year clinical follow-up with progressive hyperphosphatasemia (up to 5503 U/L) and with ultrasound findings and histologic diagnosis of vacuolar hepatopathy, in addition to posterior onset of HCC. A steroidogenic adrenal panel revealed an increase of adrenocortical hormones, especially progesterone and androstenedione, consistent with a subdiagnosed hypercortisolism. Euthanasia was elected and at necropsy, multinodular, yellow to red masses were observed in the liver, which were histologically and immunohistochemically defined as HCC. The association of the clinical, imaging, biochemical, adrenal panel and pathologic findings allowed to characterize and confirm a progressive disorder in this ST bitch associated with elevated adrenocortical hormones.

Hiperfosfatasemia é o aumento sérico de fosfatase alcalina, sendo que Scorrish Terriers estão predispostos a desenvolverem essa condição de patogênese desconhecida. Este trabalho descreve um caso de hiperfosfatasemia progressiva com hepatopatia vacuolar e carcinoma hepatocelular em um canino da raça Scottish Terrier. Uma cadela Scottish Terrier foi acompanhada clinicamente por cinco anos devido à hiperfosfatasemia persistente (até 5503 U/L), com achados ultrassonográficos e histológicos compatíveis com hepatopatia vacuolar, além de posterior desenvolvimento de carcinoma hepatocelular. O painel esteroidogênico realizado indicou aumento dos hormônios adrenocorticais, principalmente progesterona e androstenediona, consistente com diagnóstico de hipercortisolismo subdiagnosticado "atípico". Devido ao prognóstico desfavorável, a eutanásia foi realizada e na necropsia, massas amarelas a vermelhas e multinodulares foram observadas no fígado, com diagnóstico de carcinoma hepatocelular pela análise histológica e imuno-histoquímica. A associação dos achados clínicos, de imagem, bioquímicos, do painel androgênico e patológicos permitiram caracterizar e confirmar um distúrbio progressivo no canino da raça Scottish Terrier associado ao aumento dos hormônios adrenocorticais.

Viral diseases of sheep in Brazil: a review and current status / Doenças virais em ovinos no Brasil: revisão e status atual

The increase in sheep production is directly related to the health status of the flock. Brazil is one of the largest sheep producers in the world, and the sheep flock is concentrated in southern and northeast regions. Infectious diseases are responsible for severe economic losses resulting from a decrease in milk and meat production, deaths, and cost of treatment. Among infectious diseases, viral diseases are described chiefly in case reports or retrospective studies. This study aimed to review the main features of viral diseases that affect sheep in Brazil and their current situation in the Brazilian territory. We included eight viral diseases described in Brazil: rabies, bluetongue, contagious ecthyma, foot and mouth disease, visna-maedi, enzootic nasal tumor, ovine pulmonary adenocarcinoma, and border disease. We review the etiological, epidemiological, clinical, and pathological findings for each agent and included differential diagnoses, information on recommended diagnostic methods to confirm the disease etiology, and control measures. This study served as quick consultation material for field veterinarians for an accurate diagnosis.

O aumento da produção ovina está diretamente relacionado ao status sanitário do rebanho. O Brasil é um dos maiores produtores mundiais de ovinos, e o rebanho está concentrado nas regiões nordeste e sul do país. As doenças infecciosas são responsáveis por perdas econômicas severas que resultam da diminuição na produção de leite e carne, mortes e custos com tratamentos. Entre os agentes infecciosos, as doenças de origem viral são, em sua maioria, descritas em relatos de caso ou estudos retrospectivos. Este estudo teve como objetivo revisar as principais características das doenças virais que afetam ovinos no território brasileiro, e qual sua situação atual. Nós incluímos oito doenças virais diagnosticadas no Brasil: raiva, língua azul, ectima contagioso, febre aftosa, maedi-visna, tumor enzoótico nasal, adenocarcinoma pulmonar ovino, e pestivirose. Revisamos os achados etiológicos, epidemiológicos, clínicos e patológicos de cada agente e incluímos seus respectivos diagnósticos diferenciais, informações acerca dos métodos diagnósticos para confirmação da etiologia da doença e medidas de controle e prevenção. Esse estudo tem o propósito de servir como objetivo servir de material de consulta rápida, especialmente para veterinários de campo realizar um diagnóstico acurado.

Clinical and pathological aspects of progressive hyperphosphatasemia associated with vacuolar hepatopathy and hepatocellular carcinoma in a Scottish Terrier bitch / Aspectos clínicos e patológicos da hiperfosfatasemia progressiva associada à hepatopatia vacuolar e carcinoma hepatocelular em uma cadela da raça Scottish Terrier

ABSTRACT: Hyperphosphatasemia refers to an increase in alkaline phosphatase serum activity, and Scottish Terriers (STs) are predisposed to develop this condition of uncertain pathogenesis. This study describes a case of progressive hyperphosphatasemia with vacuolar hepatopathy and hepatocellular carcinoma (HCC) in a ST bitch. This dog had a five-year clinical follow-up with progressive hyperphosphatasemia (up to 5503 U/L) and with ultrasound findings and histologic diagnosis of vacuolar hepatopathy, in addition to posterior onset of HCC. A steroidogenic adrenal panel revealed an increase of adrenocortical hormones, especially progesterone and androstenedione, consistent with a subdiagnosed hypercortisolism. Euthanasia was elected and at necropsy, multinodular, yellow to red masses were observed in the liver, which were histologically and immunohistochemically defined as HCC. The association of the clinical, imaging, biochemical, adrenal panel and pathologic findings allowed to characterize and confirm a progressive disorder in this ST bitch associated with elevated adrenocortical hormones.

RESUMO: Hiperfosfatasemia é o aumento sérico de fosfatase alcalina, sendo que Scorrish Terriers estão predispostos a desenvolverem essa condição de patogênese desconhecida. Este trabalho descreve um caso de hiperfosfatasemia progressiva com hepatopatia vacuolar e carcinoma hepatocelular em um canino da raça Scottish Terrier. Uma cadela Scottish Terrier foi acompanhada clinicamente por cinco anos devido à hiperfosfatasemia persistente (até 5503 U/L), com achados ultrassonográficos e histológicos compatíveis com hepatopatia vacuolar, além de posterior desenvolvimento de carcinoma hepatocelular. O painel esteroidogênico realizado indicou aumento dos hormônios adrenocorticais, principalmente progesterona e androstenediona, consistente com diagnóstico de hipercortisolismo subdiagnosticado "atípico". Devido ao prognóstico desfavorável, a eutanásia foi realizada e na necropsia, massas amarelas a vermelhas e multinodulares foram observadas no fígado, com diagnóstico de carcinoma hepatocelular pela análise histológica e imuno-histoquímica. A associação dos achados clínicos, de imagem, bioquímicos, do painel androgênico e patológicos permitiram caracterizar e confirmar um distúrbio progressivo no canino da raça Scottish Terrier associado ao aumento dos hormônios adrenocorticais.

Acute Oral Chromium Exposure Resulting in Ulcerative Gastritis and Perforated Ulcers in Swine.

Heavy metal poisoning poses a challenge in diagnostic practices and environmental safety. This study describes the epidemiological, clinical, and pathological aspects of a chromium (Cr) poisoning outbreak in growing/finishing pigs housed in pens with bedding of pine wood shavings containing Cr. A visit to the affected farm was conducted. Epidemiological data were collected, and necropsy and histopathological examinations and heavy metal quantifications were performed. Up to 30% of the animals from the affected pens displayed clinical signs 48 h after housing, characterized by apathy, rigid gait, distended abdomen, pain to abdominal palpation, fever, vomiting, and skin cyanosis. The lethality rate reached 76.6%. Main postmortem findings consisted of ulcerative gastritis with perforation of the glandular stomach in all necropsied swine. Heavy metal analysis revealed a higher concentration of Cr in the bedding of the affected pens, along with elevated levels of Cr in the livers of the affected swine. Given that Cr is a known cause of poisoning in humans (with acute oral exposure resulting in corrosive lesions in the gastrointestinal tract), this study marks the first diagnosis of acute oral natural Cr poisoning in animals. This diagnosis was established through the association of epidemiological, pathological, and heavy metal quantification data.

Outbreak of toxoplasmosis associated with muscular lesions in finishing pigs caused by an atypical Toxoplasma gondii genotype.

Toxoplasma gondii infections are usually asymptomatic in pigs, and an acute clinical disease is rare in this host. This study aimed to determine the pathological and molecular aspects of an outbreak of fatal systemic toxoplasmosis in finishing pigs in Brazil. The outbreak occurred on a commercial finishing pig farm in the state of Santa Catarina in southern Brazil. The farm had 1500 pigs and 3.8% of mortality rate during the outbreak. The pigs had fever, anorexia, apathy, and locomotor deficits. Seven pigs were necropsied. Gross findings included multifocal to coalescent pale areas in skeletal muscles, lymphadenomegaly, hepatosplenomegaly, and non-colapsed lungs. The histological findings included granulomatous lymphadenitis, hepatitis and splenitis, necrotizing myositis, and lymphoplasmacytic interstitial pneumonia. Lung and liver lesions were occasionally accompanied by T. gondii parasitic structures. Positive immunolabeling for T. gondii tachyzoites and encysted bradyzoites was detected in all examined pigs. PCR-RFLP (11 markers) and microsatellite analysis (15 markers) identified the non-archetypal genotype #278 in pigs. This is the first report of systemic toxoplasmosis in pigs with muscle lesions and additionally shows the diversity of disease-causing T. gondii genotypes circulating in animals in Brazil.

Pathological and etiological characterization of cases of bovine abortion due to sporadic bacterial and mycotic infections.

Opportunistic bacteria and fungi are commonly reported causes of bovine abortion in a small percentage of fetal losses of infectious etiology in cattle. The objective of this study was to characterize the pathological and etiological findings in fetuses aborted due to secondary bacterial and fungal infections submitted for postmortem examination between 2004 and 2019 in the State of Rio Grande do Sul, Brazil. Nineteen cases of bacterial etiology and five cases of fungal etiology were assessed. In cases of bacterial etiology, gross changes were uncommon and two different microscopic patterns were observed: (1) primary bronchopneumonia with occasional dissemination in cases of Staphylococcus sp., Streptococcus sp., and Mannheimia haemolytica infections; and (2) systemic disease with sepsis in cases of Escherichia coli and Listeria sp. infections. Aspergillus sp. was the main fungal agent identified, and cases of mycotic abortion were characterized by placentitis, dermatitis, and pneumonia. Fetal membranes were available for examination in less than half of the submissions (11/24), and placental lesions were observed in all cases. This study reaffirms the importance of postmortem examinations in the determination of causes of fetal loss in cattle and highlights pathological findings commonly observed in fetuses aborted due to sporadic bacterial and fungal agents.

Non-ambulatory pigs in two Brazilian growing-finishing farms: a clinic, etiological and pathological perspective on 76 cases.

BACKGROUND: Non-ambulatory pigs, colloquially known as downers or downed pigs, are animals presented with limited to no mobility, usually as a result of pre-existing neurologic or musculoskeletal conditions. Impaired ambulation is a major cause of euthanasia in pigs, leading to economic losses and animal welfare concerns. Additionally, reaching the underlying diagnosis of impaired ambulation in pigs is commonly a challenging task for swine practitioners. The aim of this necropsy-based study was to report the clinical, etiological, and pathological findings of 76 non-ambulatory grower-finisher pigs, and to correlate tail-biting lesions with the causes of death/reason for euthanasia in non-ambulatory pigs. Necropsies of downed pigs were performed during on-site visits to two pig farms in southern Brazil. RESULTS: The diagnosis of the conditions was based on the clinical, macroscopic, histopathological, bacteriological, immunohistochemical, and molecular findings. The diseases diagnosed in non-ambulatory pigs in this study were suppurative arthritis (29/76), suppurative spondylitis (10/76), PVC-2 associated diseases (8/76), bone fracture (7/76), non-suppurative meningoencephalomyelitis (4/76), suppurative meningoencephalitis (6/76), fibrocartilaginous thromboembolism (3/76), epiphysiolysis (3/76), ascending bacterial myelitis (3/76), and other conditions (3/76). The frequency of suppurative arthritis, suppurative spondylitis, and ascending bacterial myelitis/meningitis was higher in pigs with tail biting lesions than controls (P < 0.001). CONCLUSIONS: Non-ambulatory pigs were observed during the entire rearing period, however, the occurrence of non-ambulatory pigs increased in animals aged ≥ 150 days. Infectious diseases were the most common cause of downed pigs, mainly associated with chronic bacterial infections. Tail biting lesions were an important predisposing factor to suppurative arthritis, suppurative spondylitis, and ascending bacterial myelitis/meningitis.

Pathological aspects of cutaneous mast cell tumors with metastases in 49 dogs.

Cutaneous mast cell tumor (MCT) is one of the most frequent cutaneous neoplasms of dogs and may vary from well-differentiated to aggressive tumors with metastasis. The authors retrospectively described the gross and histologic aspects of metastatic MCT in 49 dogs. Primary MCT was most commonly identified in the inguinal region (14/35; 40%), and at necropsy multiple, cutaneous nodules were frequently reported (23/49; 47%). All primary MCT were classified as high-grade neoplasms, and metastases involved the lymph nodes (47/49; 96%), spleen (33/49; 67%), liver (29/49; 59%), bone marrow (20/49; 41%), kidneys (16/49; 33%), and heart (14/49; 29%), while the lungs were less commonly affected (9/49; 18%). The main gross findings included lymphadenomegaly in 47 cases; splenomegaly in 28 cases, with splenic nodules in 13 dogs; hepatomegaly in 28 cases, with white pinpoint foci in 9 cases; nodules on the capsular surface of the kidneys in 9 dogs; and epicardial nodules in 6 cases. Histologically, the lymph nodes were largely obliterated by neoplastic mast cells, while in the spleen, neoplastic cells were multifocally scattered (16/33; 48%), arranged in nodules (10/33; 30%), or obliterated the parenchyma (9/33; 27%). In the liver, the neoplastic cells mainly infiltrated the sinusoids (24/29; 83%), but were also arranged in random nodules (10/29; 34%). Interstitial and nodular metastases were observed in the kidneys and the heart. Grossly unapparent metastases were common in the heart (6/14; 43%), kidneys (4/16; 25%), and lungs (6/9). KIT III and KIT II staining patterns were observed in 29 and 20 cases, respectively.

Generalized and fatal felid alphaherpesvirus-1 natural infection with liver involvement in a feline leukaemia virus-positive adult cat: a case report.

Generalized and fatal felid alphaherpesvirus-1 (FeHV-1) natural infection with liver involvement is rarely reported in cats, and the occurrence of herpesvirus viraemia with internal organ histologic lesions in adult cats is unknown. A 1.5-year-old cat, female, mixed breed, positive for feline leukaemia virus (FeLV) presented in a veterinary teaching hospital with sneezing, nasal discharge, anorexia, and diarrhoea after two weeks, evolving to inspiratory dyspnoea. Complete blood count and serum biochemistry analysis showed marked leukopenia and thrombocytopenia. After clinical worsening and lack of treatment response, the cat was euthanized. Pathological findings included hepatic necrosis, fibrinonecrotic tracheitis, and bronchointerstitial pneumonia. Marked amounts of coccobacillary bacteria were observed covering the necrotic tracheal and bronchial mucosa, at the cytoplasm of alveolar macrophages, and free in alveoli lumen, mimicking a primary bacterial tracheitis and pneumonia. Both lung and tracheal bacteria exhibited marked immunolabeling in anti-Escherichia coli immunohistochemistry. In addition, rare epithelial cells of bronchi contained round, eosinophilic, intranuclear viral inclusion bodies (4-7 µm) that marginate the chromatin, characteristic of FeHV-1 infection. Strong multifocal anti-FeHV-1 immunolabeling was observed in necrotic epithelial cells of the liver, trachea, and lungs. Generalized herpesvirus infection with the occurrence of acute hepatic necrosis and severe respiratory illness is a potential differential diagnosis in FeLV-positive cats with respiratory signs. The immunodepression in these cats probably favours a FeHV-1 viraemia in addition to the development of opportunistic bacterial infections, such as Escherichia coli, and it is associated with a poor outcome.