Histopathological study of pulmonary lesions and molecular detection of pasteurellosis and mycoplasmosis in Fariman slaughter house

The most economically significant bacterial pneumonias are pasteurellosis and mycoplasmosis as causative agents of reduction in production, weight loss, increasing mortality rates in dairy and fattening sheep herds. This study was conducted to determine the histopathological and molecular properties of lung lesions caused by pasteurellosis and mycoplasmosis in slaughtered sheep at Fariman. A total of 4960 lungs were collected from sheep slaughtered at Fariman abattoir in 2019-2020. 90 of 4960 (1.81%) lungs which were macroscopically suspected to be suffering from pneumonia were examined microscopically. The polymerase chain reaction test was carried out for molecular detection of Pasteurella multocida and Mycoplasma ovipneumonia. Furthermore, statistical analysis was performed using the Chi-square test and the data were analyzed by SPSS software version 20. The molecular analysis showed that 16 specimens (0.032%) were positive for P. multocida, but M. ovipneumonia was negative in all specimens. In the histopathological investigation, the most common lesion was suppurative bronchopneumonia (1.16%). In addition, there was no significant association between age, sex and season with P. multocida (P˃0.05). These findings revealed that P. multocida is one of the common cause of bacterial pneumonia in slaughtered sheep at Fariman and its histopathological characteristics are notable.