Evaluation of a new transdermal Mycoplasma hyopneumoniae bacterin to control mycoplasmal pneumonia in pigs experimentally co-infected with PRRSV and Mycoplasma hyopneumoniae

摘要

Mycoplttsma hyopneumoniae, the causative agent of en-zootic pneumonia, induces a mild, chronic pneumonia commonly complicated by opportunistic infections with other bacteria. Porcine reproductive and respiratory syndrome virus (PRRSV) remains one of the most important pathogens in the swine industry, PRRSV and M hyopneumoniae are the two pathogens found most frequently in the porcine respiratory disease complex (PRDC), an economically significant respiratory disorder characterized by slow growth, decreased feed efficiency, lethargy, anorexia, fever, cough and dyspnea. Research conducted in our laboratory found that M hyopneumoniae potentiated the pneumonia induced by PRRSV as measured by significantly prolonged and increased the severity of PRRSV-induced pneumonia. Microscopically, lesions typical of M hyopneumoniae were more extensive in the dual infected pigs. However, no obvious potentiation of the M hyopneumoniae-in-duced pneumonia was observed macroscopically. These results suggest that controlling M hyopneumoniae infection is an important intervention strategy in the control of PRDC and PRRSV induced respiratory disease.