3.4. Lung lesion scoring
The percentage of pigs at slaughter with lung lesionsand pleuritis and also the severity of pneumonia lesions are shown in Table 4. The prevalence of pneumonia lesions ranged from 38% (herd 3) to 98% (herd 1) and the prevalence of pleuritis from 2% (herd 3) to 23% (herd 1).The severity of pneumonia lesions was lowest in herd 3 (1.7), and highest in herd 1 (11.9).