challenged pigs was detected in the mhp183 qPCR assay.For tissues, a CT cutpoint of 33 (equivalent to 0.023 ng of M.hyopneumoniae DNA/mL of tissue extract) was selected on the basis of histopathology results for right and left lung samples from challenged pigs, and yielded a sensitivity of 97.3% and specificity of 100% (Fig. 3).