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Kill more Pasteurella the (Pasteurella mutocida, Pm) is the main pathogens of the bovine hemorrhagic septicemia, sporadic or endemic diseases caused by bacteria, mainly as sepsis and hemorrhagic inflammation, fever, pneumonia or acute gastric enteritis and visceral extensive bleeding as the main feature. At home and abroad caused by bacteria calf pneumonia has rarely been reported. In 2007, Shihezi, Xinjiang has six large-scale dairy farms 1-9 weeks old calves sudden onset, a total of more than 90 calves died, the main clinical symptoms of fever, cough, diarrhea is characterized by. In order to determine the cause the calf disease cause of death, to avoid the spread of the disease and effectively control the spread of the disease. Acquisition incidence calves diseased Pathogen culture characterization, physiological, biochemical and molecular biological identification, animal infection test isolates, detection of virulence factors and susceptibility testing. The results are as follows: 1,4 isolates were gram-negative short bacillus, rounded at both ends. Isolates morphological characteristics and cultural characteristics consistent with previous cause of adult cattle sepsis like Pasteurella isolates biochemical identification results and kill more the Pasteurella biochemical characteristics. Reference kill Pasteurella species specific gene kmtl and the capsular serotype specific gene HYAD-HYAC bcbD dcbF ecbJ, fcbD sequence to design primers for four isolates with multiplex PCR amplification results isolates could be amplified less than 500bp and 1000bp bands, Actinobacillus pleuropneumonia, enterococci and E. coli as a template can be amplified specific bands, send the sequence in GenBank nucleotide than , indicating that the isolates were capsular serum type A Pasteurella multocida. And those who primer Kmtl amplification for positive strains biochemical results are in line with the PM standard. Pure culture isolates were inoculated mice, rabbits, experimental animal pathogenic isolates showed strong pathogenicity test group of mice all died within 48h, the rabbits were 72 hours after death, can be recovered from the dead rabbits and mice inoculated with bacteria. 4, susceptibility test results show that the separation of 4 pm ofloxacin, gentamicin higher sensitivity. To ciprofloxacin, neomycin sensitivity is not high, but for ampicillin sodium sensitivity. In our study, more than kill Pasteurella multocida the iron uptake related tbpA gene encoding type 4 of pili ptfA gene, isolates the detection of virulence factors, the results of sequencing analysis detected only ptfA genes. From calves, mice, rabbits pathological histological changes visible primary lesions in the lungs, alveolar wall can be seen telangiectasia congestion, alveolar serous edema, alveolar cellulosic exudate, which shows a small amount of neutrophils and erythrocytes. Other organs are varying degrees of bleeding. The results confirmed that the isolates of Pasteurella multocida. This is the first confirmed Xinjiang region killed Pasteurella multocida capsular serum caused by type A calf pneumonia, and systematic study of the Xinjiang Pasteurella multocida biological characteristics, while establishing a common biochemical identification to molecular biology fast detection diagnostic mode.
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