Download full article: V.2,-N.1,-01-20881_2009_12_30_20_27
Download full article: V.2,-N.1,-02-20881_2009_12_30_20_43
Bovine eurytrematosis in Brazil is induced by Eurytremacoelomaticum and is endemic in some Brazilian States. The pathology of the disease is not fully understood and there are few descriptions of the histopathological associated lesions. This study analyzed the histopathological patterns of 117 bovine pancreatic samples obtained randomly. Samples were collected during one year from the municipal slaughterhouse of Campo Mourão, Paraná, Brazil, during routine meat inspection; this location is endemic for bovine eurytrematosis. Five predefined histopathological patterns were analyzed. Differences between the types of lesions were analyzed statistically. The pancreas of 11.97% (14/117) animals was normal; 31.62% (37/117) demonstrated initial proliferative periductal lesions; 17% (21/117) revealed severe proliferative periductal lesions; 21.37% (25/117) were characterized as chronic multifocal interstitial pancreatitis; while 17.09% (20/117) demonstrated chronic diffused interstitial pancreatitis. Statistically cases classified as initial proliferative interductal and chronic multifocal interstitial pancreatitis were the most frequently occurring lesions. The pathogenesis of lesions associated with this disease is also discussed.
Key Words: Eurytrema coelomaticum, pathology, cattle, pancreas.
Download full article: V.2,-N.1,-03-20881_2009_12_30_21_42
The objectives of this work were: 1) to investigate L. intracellularis antibodies in grower-finisher pigs from 30 herds by immunofluorescent antibody test (IFAT) 2) To evaluate the porcine proliferative enterophaty (PPE) lesions by histopathology, histochemistry (Warthin Starry) and immunohistochemistry (IHC) in ileum samples obtained at slaughterhouse from 10 ed herds, 9 seropositive and 1 control seronegative. At each farm, 30 grower-finisher pigs (18 to 20 weeks old pigs) were randomly ed for blood sampling. The sera were analyzed with a commercial IFAT kit (IleiTest, Elanco Animal Health). The overall percentage of positive pigs was 31.2% (281/900), whereas the percentage of positive farms was 76.7% (23/30). The within-herd mean percentage of positive sera ranged from 27.5 to 53.6%. Only 1 out of the 10 ed farms showed characteristic gross and histopathological lesions at slaughterhouse. On the other hand, 4 farms were positive by immunohistochemistry . In conclusion L. intracellularis infection is widespread among Argentinean farms even though the within-herd percentage was quite variable. Slaughter pigs without microscopic lesions showed immunoreactivity to L. intracellularis.
Key Words: Lawsonia intracellularis, porcine proliferative enteropathy, swine
Download full article: V.2,-N.1,-04-20881_2009_12_30_22_25
Nile tilapias (Oreochromis niloticus)were intraperitoneally infected with a Streptococcus agalactiae suspension containing 105CFU/mL. The strain of S. agalactiae used to experimental infection was isolated from naturally infected tilapias from Paraná, south Brazil. Fishes were kept in laboratory aquaria with adequate limnologic parameters, being euthanized 3, 7, 14, 21 and 28 days post-inoculation. The isolate caused exophtalmia, ocular opacity, erratic swimming, lethargy and darkness of the skin 3, 7 and 14 post-inoculation. Histopathology revealed a septicemia with a severe mononuclear infiltrate in meninges, epicardium and eyes. Inflammation occurred mainly 3 and 7 days post-inoculation, and at 21 and 28 days was not observed. A significant association was verified between infection with S. agalactiae and the presence of melanomacrophages centers in the liver and spleen. S. agalactiae was reisolated from brain and kidney 3, 7 and 14 days post-inoculation.
Key Words: Streptococcus agalactiae, tilapia, histopathology, septicemia.
Download full article: V.2,-N.1,-05-20881_2009_12_30_22_45
An experimental study was performed in order to analyze the histopathological findings of gastrointestinal mucosa and regional lymph-nodes in piglets intoxicated with T-2 toxin as well as the mechanism of T-2 induced apoptosis in the intestinal crypt epithelia. Sixteen piglets were divided into 4 groups receiving a single oral administration of T-2 toxin. Group A: 2.5 mg T-2/kg b.w.; group B: 2 mg T-2/kg b.w.; group C: 1.5 mg T-2/kg b.w.; group D: control group without toxin. Organ lesions were classified in grades 0 to 4 according with severity and were statistically analyzed. Apoptosis was examined in intestinal sections only in groups A and D. Group A piglets showed clinical signs and pathological changes related with those seen in circulatory shock. Microscopic lesions were observed only in pigs from groups A and B. In stomach, lesions consisted of congestion, hemorrhages and necrotic cells in the isthmus and neck regions. Submucosal edema and necrotic crypt epithelial cells were seen in duodenum, jejunum, ileum, cecum and colon. The greatest grade of lesions was observed in colon. In lymph node, grade of lymphocytes depletion and necrosis was significantly higher in cortex than paracortex. Apoptotic bodies were present in intestinal crypt cells, lymphoid cells from lamina propria and ileal Peyer´s patches. Apoptosis seems to be the mechanism involved in the development of intestinal lesions.
Key Words: T-2 mycotoxin, pig, apoptosis, pathology.
Download full article: V.2,-N.1,-06-20881_2009_12_30_23_50
Canine hemangiopericytomas (CHP) are soft tissue neoplasms, originary from pericytes. They are frequently diagnosed in dogs and can be seen more frequently in limbs as circumscribed and firm nodules. The histopathology of CHP reveals the presence of spindle cells around blood vessels, forming whorls. In this study, cases of CHP from the Animal Pathology Service of the Veterinary Hospital of the School of Veterinary Medicine and Animal Science, registered from 1990 to 2003, were studied. All cases were reviewed and classified in the three histological subtypes recently described – perivascular (PVHP), storiform (SHP) and epithelioid (EHP). Immunohistochemical markers (vimentin, S-100 protein, CD34, Factor VIII and glial fibrillary acidic protein – GFAP) were applied to all tumors. Samples were submitted to the immunostaining of PCNA, and the labeling indexes were obtained. The mitotic index was also quantified in each subtype. Apoptosis bodies were morphologically identified in H&E stained sections, subsequently confirmed by fluorescence microscopy and then quantified in the three histological subtypes. Dog owners were contacted by telephone, and asked to inform about the outcome of their dogs. The survey revealed 61 cases of CHP, in which 21 (34.43.%) belonged to the perivascular subtype, 18 cases (29.51.%) belonged to the storiform subtype, and 22 cases (36.06.%) belonged to the epithelioid subtype. PCNA labeling index, mitotic and apoptotic indexes were significantly higher in the epithelioid subtype. Records of the follow-up of each case revealed 59% of recurrence rate in the epithelioid subtype, 55% in the storiform subtype and 17% in the perivascular subtype. According to these results, epithelioid hemangiopericytomas seem to be the most aggressive CHP subtype. Therefore, we conclude that the histopathological analysis with classification in subtypes, as well as the quantification of cell proliferation and apoptosis rates, can help in the establishment of prognosis for CHP.
Key Words: Hemangiopericytomas; Dogs; PCNA; Prognosis; Mitosis; Apoptosis.
Download full article: V.2,-N.1,-07-20881_2009_12_30_24_15
Reticuloendotheliosis virus (REV) infection can result in immunosuppression, runting syndrome, high mortality, acute reticular cell neoplasia,T- and/or B-cell lymphoma, in a variety of domestic and wild birds. Histopathological changes of reticuloendotheliosis (RE) are not sufficient to differentiate it from Avian Leukosis (AL) and Marek’s disease (MD). Currently there are no available diagnostic methods for detection of active REV infection. In order to develop immunohistochemistry (IHC) and in situ hybridization (ISH) assays for detection of REV active infections, experimentally inoculated formalin-fixed and paraffin embedded DF-1 chicken embryo fibroblasts were used as an infection model. IHC and ISH assays proved to be efficient for the detection of several REV strains, and to differentiate those strains from representative strains of the avian leukosis/sarcoma group of retroviruses (ALSV).
Key Words: Immunohistochemistry, in situ hybridization, Reticuloendotheliosis, chicken, fibroblast.
Download full article: V.2,-N.1,-08-20881_2009_12_30_24_31
Clostridium difficile is a Gram-positive opportunistic anaerobic bacterium found in the soil, water as well as the digestive tract of several species of mammals. Currently in high-health herds and not related with antibiotic treatment, C. difficile has been emerged in association with neonatal catarrhal, fibrinouspurulent colitis in 2 to 7 day-old piglets. Mesocolon edema and colitis with a “volcano” lesion are pathological key marks of C. difficile infection. In farm 1, the prevalence of neonatal piglet mesocolon edema and colitis was evaluated in an extensive study of postmortem preweaning mortality. Lectinhistochemistry pattern of normal colon and colon with edema and colitis were analyzed in order to provide more accurate information related with pathogenesis of C.difficile infection. In farm 2, a clinical description of an outbreak of neonatal colitis in piglets due to C. difficile infection was reported. A total 820 piglets were post-mortem examined, from them, 8 cases were classified as suspected of C. difficile infection (0.1%). Age of affected piglets varied between 3 to 14 days. In all of them, the key mark was the severe mesocolon edema and 2 cases were characterized by focal necrosis and loss of epithelial cells associated with a focal infiltration of neutrophils and macrophages in the lamina propria and lumen like erupted volcano. Lectins SBA and DBA that has affinity to &945; Gal epitope were negative in normal samples but reacted strongly positive at the glycocalix of the villi enterocytes of the affected samples indicating a change in the carbohydrates pattern of the cells surfaces that might favor the binding of C. difficile toxin A (TcdA). In farm 2, from 11 examined piglets, 6 of them (54%) showed different degree of mesocolon edema and in only 2 of them; volcano lesions were the main histopathological findings. Rectal swab from 8 diarrheic and 5 postmortem examined piglets were surveyed for eltA estI estII and stx2e virulence gens of E. coli andall samples were negative. Clostridium difficile toxins A and B were identified only in the sample with severe gross and microscopic changes. Isolation of C. difficile was unsuccessfully. Infection of C. difficile is present in Argentinean pig farms. Diagnosis of subclinical infection might be negligent if post-mortem studies of preweaning mortality at weekly intervals are not performed. However, when clinical disease appeared, mortality might be high as it was reported in the farm 2. Comparative lectinhistochemistry studies from field cases added further information of the carbohydrates present on glycocalix of villi enterocytes related with toxin receptors.
Key Words: Mesocolon edema, colitis, clinical disease, Clostridium difficile, pathological studies, neonatal piglets.
Download full article: V.2,-N.1,-09-20881_2009_12_30_26_34
Nodular fasciitis is a benign soft tissue lesion commonly diagnosed in human beings, but with rare description in dogs and cats. A female, spayed, 7.5 years old, otherwise healthy Labrador was examined because of a nodular growth of rapid development in the infraorbital region. The histopathological examination from the excisional biopsy revealed a well circumscribed proliferation of plump and moderately pleomorphic fibroblasts and vascular proliferation with a small central area of degeneration. Nodular fasciitis was diagnosed and several months pos surgical excision, no recurrence was observed. This report illustrates an histologically well circumscribed lesion of cutaneous nodular fasciitis in a dog, similar to some lesions in human beings and different from what is usually reported in veterinary patients.
Key Words: Nodular fasciitis, vimentin, cytokeratin, GFAP, S100, dog.
Download full article: V.2,-N.1,-10-20881_2009_12_30_28_20
This report describes two cases of cat infection by Platynosomum fastosum in the city of Belo Horizonte, Minas Gerais, Brazil. In case1, a female shorthair presented at necropsy high infestation by this fluke and had macroscopic and histopathological lesions related to P. fastosum. In case 2, a female shorthair was submitted at necropsy and didn´t showed significant lesions. At Histopathological exam of liver there were a few biliary ducts with flukes with the same characteristics of case 1. In both cases the diagnosis of P. fastosum was based on morphological appearance this fluke at histological exam. Additionally , in case 1 a parasitological analysis was performed . To authors knowledge this is the first report of P. fastosum in the city of Belo Horizonte and emphasizes the importance of this agent to be considered in the differentials related to cholangitis in cats.
Key Words: Cholangiohepatitis, Platynosomum fastosum, cat.
Download full article: V.2,-N.1,-11-20881_2009_12_30_28_54
Vesicular Stomatitis (VS) is caused by Vesicular stomatitis viruses (VSV), negative single stranded RNA arthropod-borne members of the Family Rhabdoviridae. The VSV virion is composed of the host derived plasma membrane, the envelope, and an internal ribonucleoprotein core. The envelope contains a transmembrane glycoprotein, the G protein, which mediates viral entry and exit from the cell. The ribonucleoprotein core contains the viral genome encased within the nucleocapsid protein, the N protein. The large protein (L), the nucleocapsid (N) and the phosphoprotein (P) have key roles in viral replication. The matrix protein (M protein), located between the envelope and the nucleocapsid core, participates in viral assembly, and particle budding. The VSV serotypes involved with disease in livestock are New Jersey and Indiana 1, 2 and 3. Serotypes New Jersey and Indiana 1 occur from USA through Central America to much of South America. Serotype Indiana 3 (or Alagoas) occurs in the North, Northeast and Central Brazil. The serotype Indiana 2 (or Cocal), occurs in Southern Brazil and in Argentina. Outbreaks of VS in Brazil in recent years have resulted in severe economic losses. The clinical disease in horses, cattle, and pigs is characterized by vesicles in tongue, planum nasale, planum rostrale, coronary bands (CB) of the feet, prepuce, and teats. Subclinical disease, with seroconversion and lack of vesicle formation is common under natural conditions and can be induced experimentally depending on the site of inoculation. VSV infection typically involves cytolytic infection of mammalian host cells at specific sites of inoculation. Transmission can occur via infected insect bite but animal-to-animal contact could also be important in within-herd spread. There is some evidence to suggest that biting insects may play a role in the pathogenesis of VSV infection, although mechanisms of pathogenesis are not well understood. Viral spread seems to stop at the draining lymph nodes with no viremia. As a well-known in vitro producer of interferon, it is hypothesized that the host immune response to VSV infection may limit viral spread. A better understanding of pathogenic aspects could allow development of prevention and disease control strategies.
Key Words: VSV, vesicular stomatitis, transmission, biting insects, pathogenesis.
Download full article: V.2,-N.1,-12-20881_2009_12_30_29_6