com a manifestação de resistência e susceptibilidade à doença Scrapie ( similar ovina da “doença da vaca louca” ou Encefalite Espongiforme Bovina – BSE). Translation for ‘encefalite’ in the free Portuguese-English dictionary and many Internacional de Epizootias relativa à encefalite espongiforme bovina e nos. 8 nov. Cervical CMICV – Cirurgia Minimamente Invasiva da Coluna DDD – Doença Degenerativa Discal EEB – Encefalite Espongiforme Bovina EIA.
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Neospora caninum as causative agent of bovine encephalitis in Brazil.
Neospora caninum como agente causal de encefalite bovina no Brasil. A sample of cattle presenting neurological syndrome and negative for rabies, aged 0 to 18 years, from herds in 10 Brazilian states was evaluated for N. Only the male presented severe multifocal necrotizing encephalitis associated with mononuclear cell infiltration, a pathognomonic lesion caused by parasites of the family Sarcocystidae, and only this case was associated with N.
Infected calves may be born underweight, unable to rise and with no clinical signs of disease. Hind limbs, forelimbs or both may be flexed or hyper-extended. Neurologic examination may reveal ataxia, decreased patellar reflexes, and loss of conscious proprioception. Calves may show exophthalmia or asymmetric eyes. Encephalomyelitis was the predominant lesion in live born calves but clinically affected or that developed clinical disease soon after birth and were necropsied by 2 weeks of age PARISH et al.
In Brazil, cases of neurological syndrome associated with N. The World Organization for Animal Health requires the diagnosis of causative agents of encephalitis for compliance with international sanitary standards for trade of animals and animal products OIE, Many countries have implemented new diagnostic techniques and applied them in epidemiological studies in order to participate in the global marketplace and to guarantee food safety.
In order to comply with the PNCRH, laboratories that perform rabies diagnoses are encouraged to conduct differential diagnosis of other etiological agents causing neurological syndromes when the CNS is negative for rabies virus.
Immunohistochemistry IHC is highly specific when used to identify N. To improve the sensitivity and specificity of N. The aim of this study was to examine the differential diagnosis for N.
Specimens that were negative for rabies were examined for N. A second set of sections were mounted on slides, along with controls, and processed for IHC according to Cabral et al.
As a positive control, goat fetal heart was taken from a pregnant goat that had been inoculated with the Illinois-NC strain of N. The IHC negative control was not exposed to the primary antibody. Slides were placed in a microwave oven at watts for 10 minutes for antigen retrieval.
The primary polyclonal antibody, anti- N. The amplification was a modification of Hughes et al. The amplification was a modification of Barratt et al. The first amplification was: Results, Discussion and Conclusions.
encefalite – English translation – Portuguese-English dictionary
A total of CNS specimens collected from cattle with neurological syndrome were analyzed. Convenience sampling was used, and diagnosis of encephalitis due to N. According to Dubey et al.
For this reason, histological findings should be interpreted as complementary to tests such as IHC and nested-PCR to identify the causative agent. The IHC protocol used negative control positive block without primary antibodyand it did not show non-specific staining, while the positive control evidenced cysts with typical morphological structures intensely stained by DAB, confirming it as a very specific method, as reported by Cabral et al.
The genomic nested-PCR Nc5 revealed two positive cases 0. The sequence of primers from the NC5 region was not consistent with the genomes of Toxoplasma gondiiSarcocystis capracanisS. The low frequency of CNS positive specimens for N.
It is thus not possible to determine if the positive nested-PCR represented disease neurological syndrome or latent infection. The most predominant breeds were zebu Bos indicus The two animals 0. Most cattle were female The two positive animals were a male 0.
The animals were aged 0 to 18 years.
encefalite espongiforme bovina pdf files
Most were adults over two years old Age was unknown for 6. The low prevalence of disease in this study may be associated with the low number of animals at the age of risk, given that several authors report that calves with clinical neosporosis die within the first four weeks of life DUBEY et al. The female testing positive by PCR, a 72 month-old cross-breed, did not exhibit pathological lesions in the CNS, and this may be considered a N.
The positive PCR 20 month-old cross-breed male showed clinical signs of neurological syndrome such as sialorrhea, incoordination, recumbency and paddling, and opisthotonus, and died in four days. Histological examination of the CNS revealed severe multifocal necrosis in the neuropil Figure 2meningeal mononuclear infiltrate Figure 3and mononuclear perivascular cuffing Figure 4. The clinical signs, histopathology, and PCR positivity implied that only the young male had encephalitis associated with N.
This is the espongifforme report in Brazil blvina a bovine older than one year diagnosed with N. Recent studies have associated inflammatory changes in the CNS identified by histology, positivity to molecular techniques and IHC to confirm active infection of N. When neosporosis is studied in mature animals, histopathologic findings should be combined with molecular analysis since the parasite may cause unrecognized chronic infection, or the animal may be an asymptomatic carrier, and no lesions are found because the animal is immunologically protected.
The low prevalence of N. The present study applied a protocol suggested by Baszler et al. Freezing and autolysis destroys the architecture of parasite cells, which can explain the non-visualization of parasitic cysts or tachyzoites by IHC, a technique that combines morphology and antigen binding antibodies marked with chromogen. Immunohistochemistry is a specific technique that has low sensitivity and can be effective when applied to intact tissues and those fixed in formalin EPERON et al.
Tissue fixation with formalin forms multiple connections with proteins methylene bridgeswhich masks N. In the present study antigen retrieval from CNS-tissue containing paraffin blocks was improved by heating the slides in microwave oven, as described by Cabral et al. Because veterinarians use different methods for preservation of CNS specimens that are sent to laboratorial analysis, it is required for the detection of the parasite the association of techniques that are specific, such as IHC, or nested-PCR that are both specific and sensitive, preferably in conjunction with identification of histopathological lesions SAGER et al.
Histological, microbiological, and parasitological analyses are esplngiforme for the differential diagnosis encefapite etiologic agents of encephalitis, and veterinarians should be encouraged to increase the number of CNS specimens sent for screening.
With respect to Espongiofrme. Milton McAllister for providing the positive control paraffin block, and primary polyclonal antibody against N. Anim Reprod Sci ; 2: Neospora -like protozoal infections associated with bovine abortions. Vet Pathol ; 28 2: Bovinw Neospora infection in calves born from cows that had previously aborted Neospora -infected fetuses: J Am Vet Med Assoc ; 1: Experimental reproduction of bovine fetal Neospora infection and death with a bovine Neospora isolate.
J Vet Diagn Invest ; 6 2: The development and evaluation of a nested PCR assay for detection of Neospora caninum and Hammondia heydorni in feral mouse tissues. Mol Cell Probes ; 22 4: Detection by PCR of Neospora caninum in fetal tissues from spontaneous bovine abortions. J Clin Microbiol ; 37 Effect of heat-induced antigen retrieval following inconsistent formalin fixation.
Appl Immunohistochem Mol Morphol ; 13 3: The comparative pathogenesis of neosporosis. Trends Parasitol ; 18 Diagnosis of Neospora caninum in bovine fetuses by histology, immunohistochemistry, and nested -PCR.
Braz J Vet Parasitol ; 18 4: Quantitative detection of Neospora caninum in bovine aborted fetuses and experimentally infected mice by real-time PCR. J Clinical Microbiol ; 40 4: The fluorescent antibody test. Laboratory techniques in rabies.
“encefalite” in English
World Health Organization; Arch Vet Sci [online]. Clinical, pathological and diagnostic aspects of congenital neosporosis in a series of naturally infected calves.
Vet Rec ; 4: Neospora caninum -like protozoon associated with fatal myelitis in newborn calves. J Parasitol ; 75 1: Neospora caninum – associated myocarditis and encephalitis in an aborted calf. J Vet Diagn Invest ; 2 1: Clinical neosporosis in a 4-week-old Hereford calf. Vet Parasitol ; 43 Neosporosis associated congenital limb deformities in a calf. Appl Parasitol ; 34 4: A review of Neospora caninum and neosporosis. Vet Parasitol ; 67 Hydrocephalus associated with Neospora caninum -infection in esponyiforme aborted bovine fetus.
J Comp Pathol a; 2: Structures of Toxoplasma gondii tachyzoites, bradyzoites and sporozoites and biology and development of tissue cysts. Clin Microbiol Rev b; 11 2: