Comparison of a microtitration complement-fixation test and a tube latex agglutination test for diagnosis of Mycoplasma hyopneumoniae swine pneumonia.

Comparison of a tube latex agglutination (LA) test and a microtitration complement-fixation (CF) test for the diagnosis of Mycoplasma hyopneumoniae swine pneumonia was done. In a group of 107 pigs from Iowa, Texas, and California (survey A), correlation of data on microscopic pulmonary changes with the LA and CF titers indicated the LA test might be a better indicator of microscopic lesions than the CF test. In another field study involving lungs from 50 pigs from various herds (survey B), both LA and CF test results predicted gross lesions at a 0.01 significance level, using chi-square analysis. Data from 3 Nebraska swine herds (survey C) indicated good correlation of gross and microscopic pulmonic lesions with CF and LA test results in 2 of the 3 herds. In the 3rd herd, results of the CF test failed to agree with either gross and microscopic pulmonic lesions or culture results, whereas LA test results closely correlated with these variables. Chi-square analysis at 0.5 significance level of 106 pigs from 5 Iowa specific-pathogen-free herds (survey D) indicated a correlation of CF and LA test results with the microscopic pulmonic changes of penmates.