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141.
A malignant catarrhal fever-like syndrome in indonesian swamp buffalo was experimentally transmitted to one of 2 Bos indicus and 3 of 3 Bos javanicus cattle by intravenous inoculation of 250 ml of citrated, whole blood from affected buffaloes. The 4 cattle developed clinical signs of disease on average 32.5 days after receiving the inoculation of blood. The 4 cattle died after a variable period of illness. None of a further 3 B. javanicus cattle inoculated intravenously with a spleen homogenate prepared from another affected buffalo developed the disease. The experimental disease was clinically and pathologically similar to the natural disease in buffaloes although differences were noted. Attempts to adapt the agent to mice, guinea pigs and rabbits failed. A cytopathic agent (Japanese encephalitis virus) was isolated from the spleen of one buffalo with clinical signs but was not considered significant. Sixty-three B. indicus, 7 B. javanicus (and 6 of their crosses), 3 B. taurus and 4 Bubalus bubalis (Murrah buffalo) were kept in the same quarters where 50 of 177 swamp buffaloes died between September 1979 and May 1982. Four of the 7 B. javanicus cattle developed the clinical signs of disease and died. All the other cattle in contact remained healthy.  相似文献   
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A fifth stage Strongylus vulgaris migrated through the spinal cord of a 2-year-old, male donkey resulting in progressive paraparesis and then tetraplegia. A profound neutrophilic pleocytosis was detected on analysis of cerebrospinal fluid. The parasite appeared to have entered the mid-lumbar spinal cord, migrated to the cranial thoracic segments, exited, then re-entered the spinal cord a few segments craniad. It then traveled further cranially and was found in the third cervical spinal cord segment. Some parts of the lesion were remarkably free from tissue necrosis, hemorrhage and inflammation. Severe granulomatous myelitis with hemorrhage and necrosis were seen at other sites. The latter were quite similar to lesions seen in equine protozoal myeloencephalitis.  相似文献   
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In order to assess the role of Alcaligenes faecalis in respiratory disease of broilers, a study was conducted to determine the prevalence of this bacterium in North Carolina broilers and to determine the relationship of A. faecalis infection to clinical disease. Our studies showed that A. faecalis is prevalent in North Carolina commercial broilers during the winter months. Bacteriological examination of turbinates and tracheas revealed that almost 40% of individual birds between 35 and 45 days of age yielded positive cultures; 62% of tested flocks were infected. When present, A. faecalis was usually the predominant bacterium isolated. Furthermore, because of a higher frequency of A. faecalis isolation in broiler flocks with respiratory disease (75% vs. 29% in flocks without respiratory diseases), these studies suggest a causal relationship between this bacterium and clinical respiratory disease.  相似文献   
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A single-dilution indirect solid-phase radioimmunoassay (IRIA) was developed for the detection of low levels of anti-pseudorabies immunoglobulin G in swine sera. The assay derived increased sensitivity from the use of a second amplifying antibody. The IRIA was examined for its stoichiometry, amplification by secondary antibody, advantage of a single-dilution assay vs an end-point titration, sensitivity, and specificity. The assay had a near linear dose-response relationship with positive sera (serum-neutralization titer less than or equal to 1:16) and lacked a dose response with negative sera. With addition of the secondary antibody, the IRIA was enhanced 8.5-fold in net specific binding, and the end-point titer was amplified 32-fold. The single-dilution assay was proved to be a feasible test, compared with end-point titration. Anti-pseudorabies virus titers were at least 128-fold higher by IRIA than those by serum-neutralization test. Evidence indicated that there may be minimal or no cross-reactivity of IRIA antigen with anti-infectious bovine rhinotracheitis sera. The single-dilution IRIA was a rapid and sensitive test for anti-pseudorabies virus immunoglobulin G in swine sera.  相似文献   
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