3.2. Results of testing BAL fluid samples
The results of the analyses of BAL fluid in the 6-, 10-, 14- week-old pigs and at slaughter are presented in Table 3. In general, the number of animals that tested positive for M.hyopneumoniae in BAL fluid increased with increasing age of the animals (P < 0.05), with almost all animals positive at slaughter age. The average number of M. hyopneumoniae organisms detected in the BAL fluid by qPCR increased from 6 to 14 weeks. At slaughter, slightly lower (herds 2 and 3) or similar (herd 4) numbers of M.hyopneumoniae
organisms were found than at 14 weeks, except for herd 1
where the numbers were highest at slaughter.