Francisella salimarina infection in farmed cobia (Rachycentron canadum) and dusky grouper (Epinephelus marginatus) in Brazil: A case report.

This study aimed to identify and characterize isolates of Francisella salimarina associated with an outbreak on a marine fish farm in Brazil and to analyse their genetic variability and antimicrobial susceptibility. In 2021, diseased cobias (Rachycentron canadum, n = 10) and dusky groupers (Epinephelus marginatus, n = 10) were sampled and subjected to bacteriological and pathological examinations. The isolates obtained were morphologically and biochemically characterized and identified by matrix-assisted laser desorption/ionization-time of flight (MALDI-ToF) and 16S rRNA gene sequencing. The genetic diversity of these isolates was analysed using repetitive extragenic palindromic-polymerase chain reaction (REP-PCR). Antimicrobial susceptibility was assessed using the disk diffusion technique. Macroscopically, the fish presented skin ulcerations, ocular lesions, hepatomegaly and splenomegaly. A pleomorphic, gram-negative, catalase- and oxidase-positive bacterium was isolated from seven cobias and two groupers. The 16S rRNA gene sequences showed >99% coverage and identity with other deposited sequences of F. salimarina. The results of the biochemical analysis corresponded to these bacterial species. Histologically, granulomas were observed in the spleen, liver and heart of the cobias (n = 6), and necrotizing and fibrinous dermatitis and myositis were identified in some groupers (n = 2). The isolates exhibited the same banding pattern when REP-PCR was performed, indicating that they were clonally related. Finally, the antibiogram test, no inhibition halo was observed for amoxicillin and trimethoprim-sulfamethoxazole. To our knowledge, this is the first report of F. salimarina infection in cobias and dusky groupers.

Edwardsiella tarda in Tambaqui (Colossoma macropomum): A Pathogenicity, Antimicrobial Susceptibility, and Genetic Analysis of Brazilian Isolates.

Edwardsiella tarda is a crucial pathogenic bacterium in tropical aquaculture. This bacterium was recently isolated from tambaqui (Colossoma macropomum), a commercially important fish species in Brazil. This study assessed the antimicrobial susceptibility, pathogenicity, and genetic diversity of the tambaqui-derived E. tarda isolates. Fourteen bacterial isolates isolated from tambaqui were identified as E. tarda by using matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry and dnaJ gene sequencing. Antimicrobial susceptibility tests were conducted against seven drugs using the disc diffusion assay. The pathogenicity test conducted by intraperitoneal injection of 2.4 × 107 colony-forming units (CFU) fish-1 of E. tarda (ED38-17) into tambaqui juveniles eventually revealed that neither clinical signs nor death were present. However, splenomegaly and whitish areas in the spleen and kidneys were observed. The histological investigation also revealed granulomatous splenitis, nephritis, and hepatitis occurring internally. Repetitive extragenic palindromic-PCR fingerprinting separated the 14 isolates into three genetic groups. The antibiogram revealed that all E. tarda isolates were wild-type (WT) to florfenicol (FLO), norfloxacin (NOR), neomycin (NEO), erythromycin (ERY), and oxytetracycline (OXY); however, some were non-wild-type to sulfamethoxazole/trimethoprim (7.1%) and amoxicillin (21.4%). Therefore, through experimental infection, E. tarda ED38-17 could induce pathogenic effects in C. macropomum. Additionally, three distinct genetic types were found, and the E. tarda isolates were WT to FLO, NOR, NEO, ERY, and OXY. These findings raise awareness of a bacteria causing unseen lesions, a pathogen that will potentially impact tambaqui aquaculture in the future.

Tilapia lake virus (TiLV) causes severe anaemia and systemic disease in tilapia.

Tilapia lake virus disease (TiLVD) is an emerging disease in tilapia that is associated with mass mortality affecting global tilapia aquaculture. In this study, red hybrid tilapias (Oreochromis spp.) were experimentally infected by intracoelomic injection with Tilapia lake virus (TiLV) to gain a better understanding of the clinicopathological changes during infection. Pale bodies and gill were observed in infected fish after 7 days of post-challenge (dpc) associated with severe anaemia. Further haematological analysis in TiLV-infected fish revealed decreased levels of haemoglobin and haematocrit at 3 dpc. Common pathological findings included pale and friable liver, pale intestine with catarrhal content, and dark and shrunken spleen in TiLV-infected fish at 7 dpc and 14 dpc. Histologically, reduced numbers of red blood cells and accumulation of melano-macrophage centre in the spleen were found in infected fish at 3 dpc, and severe lesions were more commonly observed at 7 and 14 dpc. Lymphocyte infiltration, syncytial cell formation and multifocal necrotic hepatitis were the prominent pathological findings in the liver of infected fish. The severity of pathological changes was associated with TiLV-infection with higher viral loads and with the expression pattern of pro-inflammatory cytokines and antiviral genes, including interferon regulatory factor 1 (irf1), interleukin (il-8), radical s-adenosyl methionine domain containing 2 (rsad2) and mx. Our study provides a comprehensive analysis of the haematological profile and pathological changes in tilapia during TiLV infection. Overall, lesions present in various organs, together with alteration of host immune response in TiLV-infected fish, indicate the systemic infection of this virus. The knowledge gained from this study improves our understanding of how TiLV causes pathological and haematological changes in tilapia.

Inclusion of fibroblasts and collagen fibrils in the cytologic grading of canine cutaneous mast cell tumors.

BACKGROUND: Fibroblasts and/or collagen fibrils have not been included in previous cytologic grading schemes of canine mast cell tumors (MCTs), and their association with biological behavior is broadly debated. OBJECTIVES: This study aimed to evaluate the cytologic findings of canine MCT, with emphasis on the microenvironment, and propose a novel cytologic grading system correlated with mortality and histologic grade. MATERIAL AND METHODS: Cytology smears of canine cutaneous MCTs were retrospectively reviewed and compared with their histopathologic counterparts using Cohen´s Kappa test. One-year survival rates were also compared with the cytologic and histopathologic variables using Pearson´s correlation test. RESULTS: From 92 first-occurrence canine cutaneous MCTs, the five features most associated with mortality were selected for a new grading system. The five features were cytoplasmic granulation, fibroblast and/or collagen fibril concentrations, and the presence of mitotic figures, multinucleation, and karyomegaly. Among concordant histopathologic and cytologic cases (ie, the same grades using both systems), mortality rates were 2.6% (1/38) for low-grade and 71.4% (10/14) for high-grade cases (P < 0.001, chi-square). For false-negative and false-positive results, mortality rates were 33% (1/3) and 45% (5/11), respectively (P = 0.707). CONCLUSIONS: Unlike the Camus cytologic grading system, the present amendment excluded binucleation and included fibroblasts and/ or collagen fibrils, which in higher concentrations were associated with increased survival and a low histopathologic grade. Cytologic grading with the inclusion of fibroblast and collagen fibril concentrations correlated with survival, as did the Camus cytologic and Kiupel histopathologic grades; however, further studies are needed to confirm the prognostic value of this novel cytologic grading scheme.

Isolation, Identification and Characterization of a Novel Megalocytivirus from Cultured Tilapia (Oreochromis spp.) from Southern California, USA.

In spring 2019, diseased four-month-old tilapia (Oreochromis spp.) from an aquaculture farm in Southern California, USA were received for diagnostic evaluation with signs of lethargy, anorexia, abnormal swimming, and low-level mortalities. At necropsy, non-specific external lesions were noted including fin erosion, cutaneous melanosis, gill pallor, and coelomic distension. Internal changes included ascites, hepatomegaly, renomegaly, splenomegaly, and multifocal yellow-white nodules in the spleen and kidney. Cultures of spleen and kidney produced bacterial colonies identified as Francisella orientalis. Homogenized samples of gill, brain, liver, spleen, and kidney inoculated onto Mozambique tilapia brain cells (OmB) developed cytopathic effects, characterized by rounding of cells and detaching from the monolayer 6-10 days post-inoculation at 25 °C. Transmission electron microscopy revealed 115.4 ± 5.8 nm icosahedral virions with dense central cores in the cytoplasm of OmB cells. A consensus PCR, targeting the DNA polymerase gene of large double-stranded DNA viruses, performed on cell culture supernatant yielded a sequence consistent with an iridovirus. Phylogenetic analyses based on the concatenated full length major capsid protein and DNA polymerase gene sequences supported the tilapia virus as a novel species within the genus Megalocytivirus, most closely related to scale drop disease virus and European chub iridovirus. An intracoelomic injection challenge in Nile tilapia (O. niloticus) fingerlings resulted in 39% mortality after 16 days. Histopathology revealed necrosis of head kidney and splenic hematopoietic tissues.

LIQUID NITROGEN CRYOSURGERY FOR CUTANEOUS AND OCULAR NEOPLASMS IN KOI (CYPRINUS CARPIO) AND GOLDFISH (CARASSIUS AURATUS): EIGHT CASES (2018-2019).

Cryosurgery, also known as cryotherapy and cryoablation, is a promising surgical technique that employs highly localized freezing to destroy damaged and diseased tissue, including benign and malignant neoplasms. This procedure has been reported in the treatment of chromatophoromas, fibromas, and peripheral nerve sheath tumors in piscine patients. This study presents eight clinical cases of cryosurgery on cyprinid pet fish for a wide array of neoplastic masses, including chromatophoromas, squamous cell carcinoma, and sarcomas that were diagnosed by histopathology. Surgical excision of external masses, liquid nitrogen cryotherapy, injectable medications (meloxicam and danofloxacin), and topical medical-grade honey were applied to the patients after biopsy sampling. Five out of seven cutaneous cases and two out of three ocular cases had complete resolution without recurrence for at least three months posttreatment. Treatment was unsuccessful for two of the cutaneous cases in which the cutaneous masses were extremely invasive, resulting in severe ulceration and deep invasion into the coelomic cavity. One of the ocular cases involved a corneal mass that did not change in size and had no complications after treatments, suggesting that the treatment might be useful in limiting growth. The effectiveness of cryotherapy appears to correlate with the tumor type, as well as the stage and progression of tumor invasion.

Effects of nanocapsules of poly-ε-caprolactone containing artemisinin on zebrafish early-life stages and adults.

Artemisinin extracted from Artemisia annua L. plants has a range of properties that qualifies it to treat several diseases, such as malaria and cancer. However, it has short half-life, which requires making continuous use of it, which has motivated the association of artemisinin (ART) with polymeric nanoparticles to increase its therapeutic efficiency. However, the ecotoxicological safety of this association has been questioned, given the scarcity of studies in this area. Thus, in this work the toxicity of Poly (ε-Caprolactone) nanocapsules added with ART (ART-NANO) in zebrafish (Danio rerio), embryos and adults was studied. Different endpoints were analyzed in organisms exposed to ART-NANO, including those predictive of embryotoxicity and histopatoxicity. Embryotoxicity was analyzed based on Organization for Economic Co-operation and Development (OECD) test guideline (236) for fish embryo acute toxicity applied to zebrafish (Danio rerio) at 96 hpf under five nominal logarithmic concentrations (0.125 to 2.0 mg/ L). Our results demonstrate, mainly, that fertilized eggs presented increased coagulation, lack of heart rate, vitelline sac displacement and lack of somite formation. On the other hand, adult individuals (exposed to the same concentrations and evaluated after 24 and 96 h of exposure) have shown increased pericarditis. Therefore, the treatment based on ART, poly (ε-caprolactone) nanocapsules and on their combination at different concentrations have shown toxic effects on zebrafish embryos and adult individuals.

Association of colonoscopy and histopathological findings of the canine large intestine and ileum abnormalities: 54 cases series / Associação de achados de colonoscopia e histopatologia do intestino grosso e íleo de cães: série de 54 casos

Colonoscopy is a minimally invasive technique used to assess the large intestine through direct inspection of the intestinal mucosa. When associated with histopathological examination of fragments collected from the intestine, the definitive diagnosis can be obtained. This retrospective study evaluated colonoscopy and histopathological exams of the large intestine and ileum of dogs with gastrointestinal disorders admitted at the Veterinary Hospital of the Federal University of Minas Gerais (UFMG) and the Veterinary Hospital São Francisco de Assis to determine the frequency of injuries, their distribution in the intestinal segments, and the relationship of the findings observed in these two analyzes. The colonoscopy and histopathological findings of the case series were described using absolute and relative frequencies, as well as nature and intensity classification of the findings. Cohen's Kappa coefficient was obtained to assess the concordance of nature and intensity classifications between colonoscopy and histopathology, and its 95% confidence interval constructed. The analyses were performed using the Software SAS University Edition. It was observed a moderate agreement between the classification of the nature of the findings by endoscopy and histopathology (Kappa coefficient = 0.39, CI = 0.20-0.59). This can also be observed when assessing the frequency of similar diagnoses between the methods, since only 39 (72.22%) were consistent, i.e., 15 (22.78%) diagnoses differed depending on the nature of the finding, which could have a great influence on the final diagnosis if histopathology was disregarded. For the intensity of the injuries, little agreement was observed between the methods (Kappa coefficient = 0.1243, C = -0.05-0.30). This was even more evident in the frequency of similar diagnoses in terms of intensity, of which 20 (37.04%) were similar and 34 (62.96%) were different. Inflammatory affections are the most frequently observed alterations in the large intestine and ileum of dogs. The most common finding that reveals inflammatory changes is the lymphoplasmacytic infiltrate. As for the proliferative and neoplastic lesions, adenomatous polyps and lymphoma were common. The most affected sites of the large intestine were the descending colon and the rectum. Findings such as edema and reddening of the mucosa were frequent by macroscopy. Although the changes observed by colonoscopy and histopathology may not be similar, these techniques are complementary, which makes biopsies mandatory for a diagnostic conclusion.(AU)

A colonoscopia é uma técnica pouco invasiva utilizada para avaliação do intestino grosso por meio de inspeção direta da mucosa intestinal. Quando associada ao exame histopatológico, com a coleta de fragmentos do intestino, o diagnóstico definitivo pode ser obtido. O objetivo desse estudo retrospectivo foi associar os achados de exames de colonoscopia e histopatologia do intestino grosso e íleo em 54 cães com distúrbios gastrointestinais dos Hospitais Veterinários da Universidade Federal de Minas Gerais (UFMG) e São Francisco de Assis. Na colonoscopia, as alterações mais frequentemente observadas foram edema, friabilidade e avermelhamento de mucosa. Quanto à distribuição de lesões por segmento intestinal, houve maior incidência de alterações inflamatórias, das quais foram as mais frequentes, com o infiltrado linfoplasmocitário sendo o mais comum em todos segmentos analisados (i.e. reto, cólon, ceco e íleo). O cólon ascendente e o reto foram os locais de alterações mais frequentes na colonoscopia e na histopatologia. Os pólipos hiperplásicos e o linfoma foram as lesões proliferativas de ocorrência mais comum. Houve baixa concordância entre as classificações por natureza e intensidade dos achados na colonoscopia e histopatologia. Assim, não foi possível associar alterações descritas nos exames histopatológicos quanto à natureza e intensidade das lesões utilizando a colonoscopia, o que leva à conclusão de que é essencial a realização de biópsias em todos os exames para conclusão diagnóstica.(AU)

Fecal microbiota transplantation via colonoscopy in a dog with Clostridioides (Clostridium) difficile infection / Transplante de microbiota fecal via colonoscopia em um cão com infecção por Clostridioides (Clostridium) difficile

ABSTRACT: In dogs, antimicrobial therapy for Clostridioides (Clostridium) difficile infection (CDI) is based solely on metronidazole, leaving limited treatment options in case of recurrent disease. Fecal microbiota transplantation (FMT) has been successfully used in humans with recurrent CDI, whereas the usefulness of this approach is largely unknown in dogs. In the present study, a dog with a chronic-recurring diarrhea was treated with FMT via colonoscopy. CDI was confirmed by A/B toxin detection and isolation of toxigenic C. difficile from ribotype 106, a strain also commonly associated with nosocomial infection in humans. The dog recovered well after the procedure and C. difficile was no longer isolated from its stool sample. The present research suggested that FMT could be a useful tool to treat recurrent CDI in dogs, corroborating the actual protocol in humans.

RESUMO: Em cães, a terapia antimicrobiana para infecções por Clostridioides (Clostridium) difficile é baseada apenas no uso de metronidazol, limitando as opções de tratamento nos casos de recorrência. O transplante de microbiota fecal (FMT) tem sido utilizado com sucesso em seres humanos com infecções recorrentes por C. difficile, porém a utilidade desse método é ainda amplamente desconhecida em cães. O presente trabalho relata a utilização de FMT para o tratamento de um cão com diarreia crônica-recorrente por C. difficile. A infecção foi confirmada por detecção das toxinas A/B e isolamento de uma estirpe toxigênica do ribotipo 106, linhagem comumente associada a infecção em seres humanos. Após o transplante via colonoscopia, o animal se recuperou do quadro e C. difficile não mais foi encontrado em novas amostras fecais. O presente trabalho sugere que o FMT possa ser útil para o tratamento de quadros de C. difficile em cães, corroborando protocolo atual de tratamento em seres humanos.

Association of colonoscopy and histopathological findings of the canine large intestine and ileum abnormalities: 54 cases series

ABSTRACT: Colonoscopy is a minimally invasive technique used to assess the large intestine through direct inspection of the intestinal mucosa. When associated with histopathological examination of fragments collected from the intestine, the definitive diagnosis can be obtained. This retrospective study evaluated colonoscopy and histopathological exams of the large intestine and ileum of dogs with gastrointestinal disorders admitted at the Veterinary Hospital of the Federal University of Minas Gerais (UFMG) and the Veterinary Hospital São Francisco de Assis to determine the frequency of injuries, their distribution in the intestinal segments, and the relationship of the findings observed in these two analyzes. The colonoscopy and histopathological findings of the case series were described using absolute and relative frequencies, as well as nature and intensity classification of the findings. Cohens Kappa coefficient was obtained to assess the concordance of nature and intensity classifications between colonoscopy and histopathology, and its 95% confidence interval constructed. The analyses were performed using the Software SAS University Edition. It was observed a moderate agreement between the classification of the nature of the findings by endoscopy and histopathology (Kappa coefficient = 0.39, CI = 0.20-0.59). This can also be observed when assessing the frequency of similar diagnoses between the methods, since only 39 (72.22%) were consistent, i.e., 15 (22.78%) diagnoses differed depending on the nature of the finding, which could have a great influence on the final diagnosis if histopathology was disregarded. For the intensity of the injuries, little agreement was observed between the methods (Kappa coefficient = 0.1243, C = -0.05-0.30). This was even more evident in the frequency of similar diagnoses in terms of intensity, of which 20 (37.04%) were similar and 34 (62.96%) were different. Inflammatory affections are the most frequently observed alterations in the large intestine and ileum of dogs. The most common finding that reveals inflammatory changes is the lymphoplasmacytic infiltrate. As for the proliferative and neoplastic lesions, adenomatous polyps and lymphoma were common. The most affected sites of the large intestine were the descending colon and the rectum. Findings such as edema and reddening of the mucosa were frequent by macroscopy. Although the changes observed by colonoscopy and histopathology may not be similar, these techniques are complementary, which makes biopsies mandatory for a diagnostic conclusion.

RESUMO: A colonoscopia é uma técnica pouco invasiva utilizada para avaliação do intestino grosso por meio de inspeção direta da mucosa intestinal. Quando associada ao exame histopatológico, com a coleta de fragmentos do intestino, o diagnóstico definitivo pode ser obtido. O objetivo desse estudo retrospectivo foi associar os achados de exames de colonoscopia e histopatologia do intestino grosso e íleo em 54 cães com distúrbios gastrointestinais dos Hospitais Veterinários da Universidade Federal de Minas Gerais (UFMG) e São Francisco de Assis. Na colonoscopia, as alterações mais frequentemente observadas foram edema, friabilidade e avermelhamento de mucosa. Quanto à distribuição de lesões por segmento intestinal, houve maior incidência de alterações inflamatórias, das quais foram as mais frequentes, com o infiltrado linfoplasmocitário sendo o mais comum em todos segmentos analisados (i.e. reto, cólon, ceco e íleo). O cólon ascendente e o reto foram os locais de alterações mais frequentes na colonoscopia e na histopatologia. Os pólipos hiperplásicos e o linfoma foram as lesões proliferativas de ocorrência mais comum. Houve baixa concordância entre as classificações por natureza e intensidade dos achados na colonoscopia e histopatologia. Assim, não foi possível associar alterações descritas nos exames histopatológicos quanto à natureza e intensidade das lesões utilizando a colonoscopia, o que leva à conclusão de que é essencial a realização de biópsias em todos os exames para conclusão diagnóstica.

Differential diagnoses in 83 dogs with icterus / Diagnósticos diferenciais em 83 cães com icterícia

Icterus (jaundice) is a yellowish pigmentation resulting from the depositing of bilirubin in tissues due to its high plasmatic concentration. The pathogenesis of icterus includes metabolic changes or obstructed bilirubin excretion and it is classified as pre-hepatic, hepatic and post-hepatic. This study aimed to evaluate and classify different causes of icterus in dogs during post mortem examination. These dogs were examined from 2014 to 2017, using macroscopic and histologic exams as well as ancillary tests. Eighty-three dogs were examined macroscopically and microscopically. They were separated into groups of icterus types: 24 (28.9%) dogs had pre-hepatic icterus, 45 (54.2%) had hepatic, 13 (15.7%) pre-hepatic and hepatic and one (1.2%) had post-hepatic icterus. Many factors were identified as a cause of icterus, including infectious agents (51/83), neoplasms (13/83), hepatic degeneration (11/83), chronic hepatic diseases (6/83), and obstructive causes (1/87). Among the infectious causes, leptospirosis, ehrlichiosis and disorders suggestive of septicemia were diagnosed. Neoplasms associated with icterus were cholangiocarcinoma, hemangiosarcoma and lymphoma. Other causes of icterus included degenerative diseases, such as lipidosis and glycogen degeneration. Hepatic fibrosis (cirrhosis) as a chronic disease and cholelithiasis also produced icterus. PCR was performed to confirm leptospirosis and ehrlichiosis. Samples of total DNA were used to amplify a fragment of a gene from Leptospira interrogans and Ehrlichia canis. In some dogs, co-infection of these agents was detected. The classification and identification of icterus etiologies in dogs is very important due to the number of diseases with this alteration, where ante mortem diagnosis is not always easily performed when some of these conditions are present.(AU)

Icterícia é a pigmentação amarelada decorrente da deposição de bilirrubina em tecidos devido à elevada concentração plasmática. A patogênese da icterícia inclui alterações no metabolismo ou na excreção de bilirrubina, sendo classificada em pré-hepática, hepática ou pós-hepática. O objetivo desse estudo foi identificar, avaliar e classificar as causas de icterícia em cães necropsiados de 2014 a 2017, associando as lesões macroscópicas, histológicas e exames complementares. Foram avaliados macro- e microscopicamente 83 cães com diferentes intensidades de icterícia. Os cães foram separados em grupos de acordo com o tipo de icterícia: 24 (28,9%) cães com icterícia pré-hepática, 45 (54,2%) cães com icterícia hepática, 13 (15,7%) com icterícia pré-hepática e hepática e um (1,2%) com icterícia pós-hepática. Foram identificadas várias etiologias associadas à icterícia, dentre elas pode-se destacar, agentes infecciosos (51/83), neoplasmas (13/83), processos degenerativos (11/83), crônicos (6/83) e obstrutivos (1/83). Dentre as causas infecciosas, destacam-se a leptospirose, a erliquiose e as lesões sugestivas de septicemia. Entre os neoplasmas associados com icterícia destacaram-se o colangiocarcinoma, hemangiossarcoma e linfoma. Outras causas de icterícia incluiriam os processos degenerativos como as degenerações gordurosa e glicogênica. Fibrose hepática (cirrose) e colelitíase foram também diagnosticados como causa de icterícia. A PCR foi utilizada para o diagnóstico confirmatório de leptospirose e erliquiose. Amostras de DNA total foram utilizadas para amplificar um fragmento dos genes de Leptospira interrogans e de Ehrlichia canis. Em alguns cães foi detectada co-infecção por estes agentes. A classificação e a identificação das causas de icterícia em cães são relevantes devido ao grande número de doenças que apresentam essa alteração, muitas vezes sem diagnóstico ante mortem.(AU)

A review of cardiac glycosides: Structure, toxicokinetics, clinical signs, diagnosis and antineoplastic potential.

Cardiac glycosides (CGs) are secondary compounds found in plants and amphibians and are widely distributed in nature with potential cardiovascular action. Their mechanism is based on the blockage of the heart's sodium potassium ATPase, with a positive inotropic effect. Some of the most well-known CGs are digoxin, ouabain, oleandrin, and bufalin. They have similar chemical structures: a lactone ring, steroid ring, and sugar moiety. Digoxin, ouabain, and oleandrin are classified as cardenolides, consisting of a lactone ring with five carbons, while bufalin is classified as bufodienolides, with a six-carbon ring. Small structural differences determine variations in the toxicokinetics and toxicodynamics of such substances. Most case reports of poisoning caused by CGs are associated with cardiovascular toxicity, causing a variety of arrhythmias and lesions in the heart tissue. Experimental studies also describe important similarities among different CGs, especially regarding species sensitivity. Recent studies furthermore focus on their antineoplastic potential, with controversial results. Data from research studies and case reports were reviewed to identify the main characteristics of the CGs, including toxicokinetics, toxicodynamics, clinical signs, electrocardiographic, pathological findings, antineoplastic potential and the main techniques used for diagnostic purposes.

Salmonella Typhimurium - associated meningoencephalomyelitis in a foal / Meningoencefalomielite por Salmonella Typhimurium em potro

ABSTRACT: A 10-day old foal presented with a history of acute recumbency and generalized weakness, that progressed to seizure episodes and death. Post mortem examination revealed necrotizing and purulent omphalophlebitis and fibrinopurulent meningoencephalomyelitis. Salmonella Typhimurium was isolated from the central nervous system and determined to be the cause of the meningoencephalomyelitis. Due to the lack of evidence of gastrointestinal disease, the umbilical cord was considered the most likely portal of entry of the bacteria. The isolated S. Typhimurium was resistant to ampicillin and cephalotin, and partially resistant to enrofloxacin. These drugs are commonly used in the treatment of salmonellosis. This is the first report of S. Typhimurium affecting the brain and spinal cord of a foal. Salmonellosis should be considered a differential diagnosis in foals with neurologic signs, even in the absence of enterocolitis.

RESUMO: Um potro de 10 dias de idade foi admitido com histórico de decúbito e fraqueza generalizada aguda, com progressão para episódios de convulsão e morte. A avaliação post mortem demonstrou onfalite necropurulenta e meningoencefalomielite fibrinopurulenta. Salmonella Typhimurium foi isolada do material purulento coletado do sistema nervoso central. A ausência de diarreia e lesões entéricas associadas à presença de onfalite sugerem que o umbigo foi possivelmente a porta de entrada do agente. O isolado de S. Typhimurium apresentou resistência a cefalotina e ampicilina e resistência intermediária a enrofloxacina, drogas utilizadas para o tratamento de salmonelose. Este é o primeiro relato de S. Typhimurium levando a alterações encefálicas e medulares em potro. A salmonelose deve ser considerada, portanto, como diagnóstico diferencial em potros neonatos com alterações neurológicas, mesmo na ausência de enterocolite.

Improved method for diagnosis of Nerium oleander poisoning in necropsy tissues / Método aprimorado para diagnóstico da intoxicação por Nerium oleander em tecidos de necropsia

Nerium oleander is an ornamental cardiotoxic plant found in tropical and subtropical areas of the World. Its toxicity is related to the content of cardioactive glycosides, mainly oleandrin, found throughout the plant. The present study aimed to describe a new and improved method for oleandrin detection in tissue samples. The determination of oleandrin was made after extraction with a modified QuEChERS technique and measurement by UFLC-MS/MS. A total of 36 guinea pigs (Cavia porcellus) were distributed into 3 groups (n=12): control group that received only water orally (CON), and two treated groups that received hydroalcoholic oleander extract at doses of 150mg.kg-1 (OLE 150) and 300mg.kg-1 (OLE 300) in single oral dose. After three hours, fragments of heart, kidneys, liver and brain were collected for determination of oleandrin levels. The extraction and chromatographic procedures were effective for oleandrin detection and quantification in tissues, with retention time of 1.2 min and detection limit of 0.001μg g-1. The chromatographic analysis of treated guinea pigs indicated that oleandrin is distributed equally among the analyzed tissues. The developed methodology is a reliable, effective and rapid form of diagnosis of N. oleander poisoning based on necropsy tissue samples.(AU)

Nerium oleander é uma planta cardiotóxica ornamental encontrada em áreas tropicais e subtropicais do mundo. Sua toxicidade é relacionada á presença de glicosídeos cardioativos, principalmente a oleandrina, encontrada em toda a planta. O presente estudo objetiva descrever um novo e aprimorado método para detecção da oleandrina em amostras de tecido. A determinação da oleandrina foi feita após extração utilizando técnica modificada de QuEChERS e mensuração por UFLC-MS/MS. Um total de 36 cobaios (Cavia porcellus) foi distribuído em três grupos (n=12): grupo controle que recebeu apenas água por via oral (CON), e dois grupos tratados que receberam extrato hidroalcóolico de oleander nas doses de 150mg.kg-1 (OLE 150) e 300mg.kg-1 (OLE 300) em uma única dose oral. Após três horas, fragmentos do coração, rins, fígado e cérebro foram coletados para determinação dos níveis de oleandrina. A extração e procedimentos cromatográficos foram eficientes na detecção e quantificação da oleandrina nos tecidos, com tempo de retenção de 1,2min e limite de detecção de 0,001μg g-1. A análise cromatográfica dos animais tratados indicou que a oleandrina é distribuída de forma equalizada pelos tecidos analisados. A metodologia desenvolvida representa uma forma de diagnóstica segura, efetiva e rápida da intoxicação por N. oleander a partir de amostras de tecidos de necropsia.(AU)

Comparação dos efeitos das folhas de Cestrum axillare Vell. com as saponinas isoladas em caprinos / Comparison of the effects of Cestrum axillare leaves with isolated saponins in goats

Cestrum axillare Vell. (formerly Cestrum laevigatum Schltd.), family Solanaceae, is the most important hepatotoxic plant in Brazil that causes acute poisoning. It occurs in the Southeast and Center-West regions and in coastal areas of the Northeast Brazil. Spontaneous poisoning was described in cattle, goats and sheep, with clinical signs evidenced within 24 hours after ingestion of the leaves and death within 48 hours after signs onset. The clinical signs observed in acute poisoning are apathy, anorexia, ruminal arrest, arched back, constipation with feces in small spheres, sometimes covered with mucus and blood streaks, muscle tremors, staggering gait and sometimes sialorrhoea. Neurological signs may be observed, due to interference in the urea cycle due to hepatic insufficiency resulting in hyperammonemia (hepatic encephalopathy). The main pathological finding is centrilobular hepatic necrosis. The toxic principle present in C. axillare was not yet definitively proven, but some authors attribute the toxicity of the plant to the presence of saponins gitogenin and digitogenin. However, it has not been determined whether the saponins present in C. axillare are responsible for the hepatotoxic effect of the plant. Thus, the objective of this work is to determine if the saponins are the compounds responsible for the hepatotoxic effects produced by the ingestion of the leaves of C axillare, using goats as experimental model. For this, the effects of the administration of the leaves were compared with those produced by the saponins isolated from the leaves in goats. Six goats were randomly assigned to three experimental groups that received [1] dry leaves of C. axillare (animals A1 and A2), [2] saponins extract from leaves (animals S1 and S2) or [3] control group (animals C1 and C2). For goats receiving the dry leaves the administered dose of plant was 10g/kg for one animal (A1) and 5g/kg for the other one (A2). For animals receiving the saponins extract, administration was done at a dose equivalent to 20g/kg repeated after 24 hours. The dry leaves administered at a dose of 10g/kg to a goat produced toxic effects, with alterations in biochemistry (indicating hepatic lesion) and histopathology showing centrilobular hepatic necrosis. At the dose of 5 g/kg of dry leaves, clinical signs of poisoning were not observed, but hepatic necrosis was found; after 15 days after the last administration, the hepatic parenchyma of this animal was already normal, with only hemorrhagic areas, demonstrating full regeneration. The administration of extracts of saponins containing gitogenin and digitogenin to goats did not produce significant toxic effects, proving that these compounds are not responsible for intoxication. In addition, goats are a good experimental model for studies of this intoxication.(AU)

Cestrum axillare Vell. (anteriormente C. laevigatum Schltd.), família Solanaceae, é a mais importante planta hepatotóxica do Brasil que causa intoxicação aguda. Tem ocorrência nas regiões Sudeste e Centro-Oeste e em áreas litorâneas do Nordeste. A intoxicação natural foi descrita em bovinos, caprinos e ovinos, com sinais clínicos evidenciados em até 24 horas após a ingestão das folhas e morte em até 48 horas após o início da sintomatologia. Os sinais clínicos observados na intoxicação aguda são apatia, anorexia, parada ruminal, dorso arqueado, constipação com fezes em formas de pequenas esferas, por vezes recobertas com muco e com estrias de sangue, tremores musculares, andar cambaleante e, às vezes, sialorreia. Podem ser observados sinais neurológicos, devido à interferência no ciclo da ureia pela insuficiência hepática resultando em hiperamonemia (encefalopatia hepática). O principal achado patológico é a necrose hepática centrolobular. O princípio tóxico presente no C. axillare ainda não está definitivamente comprovado, mas alguns autores atribuem a toxicidade da planta à presença das saponinas gitogenina e digitogenina. No entanto, ainda não foi determinado se as saponinas presentes em C. axillare são as responsáveis pelo efeito hepatotóxico da planta. Assim, o objetivo deste trabalho é determinar se as saponinas são os compostos responsáveis pelos efeitos hepatotóxicos produzidos pela ingestão das folhas de C. axillare, usando caprinos como modelo experimental. Para isto, foram comparados os efeitos da administração das folhas com os produzidos pelas saponinas isoladas destas folhas em caprinos. Foram utilizados seis caprinos, distribuídos aleatoriamente em três grupos experimentais que receberam [1] folhas secas de C. axillare (Caprinos A1 e A2), [2] extrato de saponinas das folhas (Caprinos S1 e S2), e [3] grupo controle (Caprinos C1 e C2). Para os caprinos que receberam as folhas secas a dose administrada de planta foi de 10g/kg para um animal (A1) e de 5g/kg para outro (A2). Para os animais que receberam o extrato de saponinas, a administração foi feita na dose equivalente a 20g/kg, repetida após 24 horas. Foi verificado que as folhas secas, quando administradas na dose de 10g/kg a um caprino, produziram efeitos tóxicos, com alterações na bioquímica (indicando lesão hepática) e histopatológica apresentando necrose hepática centrolobular. Na dose de 5g/kg de folhas secas, não foi observado sintomatologia clínica da intoxicação, mas houve necrose hepática; 15 dias após a última administração, o parênquima hepático deste animal já se encontrava normal, apenas com áreas hemorrágicas, demonstrando plena regeneração. A administração do extrato de saponinas contendo gitogenina e digitogenina a caprinos não produziu efeitos tóxicos significantes, comprovando não serem estes compostos os responsáveis pela intoxicação. Além disto, a espécie caprina é um bom modelo experimental para estudos desta intoxicação.(AU)

Ichthyosis fetalis in a cross-bred lamb.

BACKGROUND: Ichthyosis is a dermatological disease characterized by varying degrees of generalized hyperkeratosis and alopecia. Two congenital forms of ichthyosis are recognized in animals: fetalis (IF) and congenita. The disease occurs rarely in cattle, swine, dogs, chickens and a goat; it has not been reported in sheep. HYPOTHESIS/OBJECTIVES: To provide clinical, laboratory and pathological assessments of a case of IF in a cross-bred lamb. ANIMALS: A male cross-bred lamb. RESULTS: Physical examination revealed apathy, fever, ectropion and eclabium. Generalized thickening and scaling of the skin was noted; this was most severe on the face, ears, inner thighs, limbs and perineum. Deep fissures and wounds were present on the hind limbs and forelimbs. The lamb was monitored for 75 days. During this period, lesions progressed and occasionally obstructed the nostrils and increasingly made it difficult for the lamb to flex major limb joints. Postmortem findings included severe epidermal thickening, multiple subcutaneous abscesses, ectropion and corneal scars. Histological findings revealed diffuse orthokeratotic hyperkeratosis, follicular keratosis, irregular epidermal hyperplasia and atrophy of the sebaceous glands. Serum vitamin A concentration was within the normal range for the species. CONCLUSIONS AND CLINICAL IMPORTANCE: This case report describes a case of presumptive ichthyosis fetalis in a lamb. Greater awareness by practitioners is required for this disease to be included in the differential diagnosis of dermatopathies in this species.

SYSTEMIC HISTIOCYTIC SARCOMA IN A COMMON HIPPOPOTAMUS (HIPPOPOTAMUS AMPHIBIUS).

A 37-yr-old captive common hippopotamus (Hippopotamus amphibius) developed lethargy and decline in mobility that progressed to death, despite supportive therapy. Histopathologic examination revealed severe, diffuse, intravascular and interstitial infiltration of neoplastic histiocytes in the spleen, liver, lymph nodes, lungs, large intestine, kidneys, and thyroid gland. Neoplastic cells were pleomorphic with marked anisocytosis and anisokaryosis, scattered multinucleated giant cells, numerous bizarre mitotic figures, and marked erythrophagocytosis. Immunohistochemistry demonstrated that neoplastic cells were positive for ionized calcium-binding adapter molecule 1 (a histiocytic marker) and negative for CD3 (a T-cell marker) and myeloperoxidase, confirming the diagnosis of systemic histiocytic sarcoma.

Syzygium cumini seed extract ameliorates adenosine deaminase activity and biochemical parameters but does not alter insulin sensitivity and pancreas architecture in a short-term model of diabetes.

BACKGROUND: The effects of the aqueous seed extract of Syzygium cumini (ASc) in a short-term model of diabetes in rats are little explored. The present study was designed to evaluate the effect of the ASc on adenosine deaminase (ADA) activity and on biochemical and histopathological parameters in diabetic rats. METHODS: ASc (100 mg/kg) was administered for 21 days in control and streptozotocin (STZ)-induced (60 mg/kg) diabetic rats. ADA activity, lipoperoxidation (cerebral cortex, kidney, liver and pancreas) and biochemical (serum) and histopathological (pancreas) parameters were evaluated. RESULTS: The main findings in this short-term model of Diabetes mellitus (DM) were that the ASc (i) significantly reverted the increase of ADA activity in serum and kidney; (ii) ameliorated the lipoperoxidation in the cerebral cortex and pancreas of the diabetic group; (iii) demonstrated hypolipidemic and hypoglycemic properties and recovered the liver glycogen; and iv) prevented the HOMA-IR index increase in the diabetic group. Therefore, the ASc can be a positive factor for increasing the availability of substrates with significant protective actions, such as adenosine. Moreover, by maintaining glycogen and HOMA-IR levels, the extract could modulate the hyperglycemic state through the direct peripheral glucose uptake. CONCLUSIONS: Our data revealed that the short-term treatment with ASc has an important protective role under pathophysiological conditions caused by the early stage of DM. These results enhance our understanding of the effect of the ASc on the purinergic system in DM.

Cistos epidermais em ovinos / Epidermal cysts in sheep

São descritos os aspectos clínico-patológicos de cistos epidermais em quatro ovinos, com idade entre dois e 12 anos, oriundos da região central do Rio Grande do Sul, Brasil. Três desses ovinos apresentavam múltiplos nódulos cutâneos, distribuídos aleatoriamente pelo corpo, e um ovino apresentava nódulo cutâneo solitário na região cervical. O período entre o aparecimento do primeiro nódulo e o surgimento de múltiplos nódulos foi de oito meses, em um caso, e um ano, em dois casos. Os quatro ovinos eram os únicos animais afetados em seus respectivos rebanhos. Os nódulos cutâneos eram redondos ou ovais, salientes, flutuantes, não pruriginosos e recobertos por pele parcialmente alopécica. Esses nódulos variavam de 1,0 a 7,0cm de diâmetro e, ocasionalmente, apresentavam um pequeno orifício central, com 1-2mm de diâmetro, na superfície externa. Ao corte eram císticos, delimitados por uma parede fina e branca, com 0,5-0,8cm de espessura, e preenchidos por material branco ou amarelado e friável. Histologicamente, os cistos eram revestidos por epitélio, contendo todos os estratos de um epitélio escamosos estratificado, sobre uma fina cápsula de tecido conjuntivo fibroso denso. Os cistos eram preenchidos por agregados homogêneos e feixes de ceratina, arranjados de forma concêntrica. Baseado na localização e características macroscópicas e histológicas esses cistos foram diagnosticados como cistos epidermais infundibulares.(AU)

The clinic and pathological aspects of four cases of epidermal cysts in sheep are described. The affected two to 12-year-old sheep were from farms in the Rio Grande do Sul state, Brazil. Three sheep showed multiple nodules, scattered randomly throughout the body, while one sheep had a single nodule on the cervical region. The period between the emergence of the first nodule to appearance of multiple nodules was approximately eight months in a case, one year in two cases, and unknown in the remaining case. These four were the only affected sheep in their respective flocks. The cutaneous nodules were round to oval, raised, fluctuant, non-pruritic and covered by wooless skin. These nodules had 1-7cm in diameter and, occasionally, revealed a small 1-2mm central pore communicating the interior of the nodule with external surface. On cut surface, the nodules were cystic, demarcated by 0.5-0.8cm in thickness white wall, and filled by abundant white to yellow, friable material. Histologically, the cyst wall was lined by a rim of tissue containing all layers of a stratified squamous epithelium. This epithelium was anchored on and supported by a thin capsule of fibrous connective tissue. The cysts were filled with homogenous aggregates or concentrically arranged streams of keratin. Based on the location and on the gross and histological findings these nodules were diagnosed as infundibular epidermal cysts.(AU)

Intoxicação experimental por aflatoxina em bezerros / Experimental aflatoxin poisoning in calves

Foram realizados dois experimentos para determinar os efeitos tóxicos de diferentes doses de aflatoxinas em bezerros, considerando-se aspectos clínicos, produtivos e patológicos. ... No primeiro experimento, o ganho de peso dos bezerros recebendo AFB1 foi equivalente ao do grupo controle durante todo período experimental. ...Durante o período experimental, e três semanas após o término desse período, não foram observados sinais clínicos e alterações histopatológicas associadas ao consumo de aflatoxinas, em qualquer dos bezerros do grupo tratamento do primeiro experimento.... Níveis alterados da atividade sérica de FA e GGT foram observados em todos os bezerros do grupo tratamento durante grande parte do período experimental. Queda acentuada do nível da AS sérica foi observada na coleta do 49º dia do experimento no bezerro que recebia a maior dose de aflatoxina. Não foram observadas variações no hematócrito e na atividade sérica da AST, nem nos níveis séricos de proteína total, bilirrubina total e bilirrubina direta em qualquer dos bezerros desse experimento. Alterações histopatológicas nos bezerros intoxicados incluíram proliferação de ductos biliares, degeneração citoplasmática vacuolar consistente com acumulação hepatocelular de lipídios, fibrose periportal, ou em ponte, megalocitose, fibrose subendotelial das veias hepáticas terminais e edema. Achados de necropsia do bezerro recebendo a maior dose de AFB1 incluíram fígado levemente aumentado de tamanho, difusamente amarelo-claro e firme, discreta ascite, edema de mesentério e submucosa do abomaso. Os dados obtidos nesses experimentos permitem afirmar que doses de 500±100 ppb de AFB1 não causam alterações patológicas e produtivas em bezerros em condições experimentais, mas podem estar associadas à mínimas alterações bioquímicas, enquanto doses de 1.250, 2.500 e 5.000 ppb de aflatoxina B1 causam doença hepática crônica em bezerros em condições experimentais.

Two experiments were performed in order to determine the toxic effects of varying doses of aflatoxins in calves. Clinical, productive and pathologic aspects of affected calves were considered….During all the experimental period of the first experiment, the weight gain of the calves receiving AFB1 was equivalent to that of the control group.…During the whole experimental period and up to three weeks after the final of the experiment, no clinical signs or histopathological changes associated with the consumption of aflatoxins were observed in any of the calves of the first experiment….Increased activity of AF and GGT were observed in all the calves of the treated group during most part of the experimental period. A marked drop in the serum levels of SA was observed in the serum sampled on the 49º day of the experiment in the calf receiving. the largest dose of aflatoxin. No changes were observed regarding PCV, TP, total bilirubin, direct bilirubin and in the serum activity of AST in any of the calves of the second experiment. Histopathological changes in intoxicated calves included bile duct proliferation, cytoplasmic vacuolar hepatocelular degeneration consistent with hepatocelular deposit of lipids, periportal to bridging fibrosis, megalocytosis, subendothelial edema and fibrosis in terminal hepatic veins. Necropsy findings in the euthanatized calf which receive de largest doses of AFB1 included slight enlargement of the liver which was firm and diffusely light-yellow, mild ascites, and edema of the mesentery and of abomasal folds. Data stemmed from these two experiments allow to conclude that AFB1 doses of 500±100 in the ration do not cause pathologic changes or decrease in productivity in calves kept in experimental conditions, but can be associated to minimal serum biochemistry; while AFB1 doses of 1.250, 2.500 e 5.000 ppb in the ration cause chronic hepatic disease in calves in kept in experimental conditions.