Lung consolidations assessment and associated bacterialpathogens detection in slaughter-aged pigs in Chiang Mai - Lamphun, Thailand

Abstract

Lung scoring assessment for consolidated lesions at the slaughtering level can be measured the severity of bacterial respiratory problem occurring at farm level. This study aims to evaluate the extent of lesion and identify the associated bacterial pathogens in slaughter-aged pigs using lung scoring and bacterial culture with PCR confirmation, respectively. The results obtained in this study could be applied in pig respiratory disease controls throughout the fattening period. From September 2016 to December 2016, a cross-sectional study was performed in 646 lung samples from 17 farm batches conducted across 3 slaughterhouses in Chiang Mai and Lamphun, Thailand. Three hundred and seventy-three (57.74%) of lung samples showed consolidation. The mean lung score for all lungs and consolidated lungs were 8.78 and 15.21, respectively. Forty-six randomly selected lung samples were tested for bacteria identification. Twenty, eleven and 13 samples tested positive for M. hyopneumoniae, M. hyorhinis and P. multocida type A, respectively. Seven lung samples had mixed infection. There was no significant difference between bacterial pathogen detected by PCR results and lung lesion score (p>0.05). This study concluded that bacterial pathogen-related pig respiratory problems are an important issue that warrants further study. Moreover, the bacterial pathogens identified from the affected lungs and vaccinated bacterins-type widely use in the area, were analogous. Strategies for bacterial pathogen control other than vaccination should be explored.