Relationship between growth during the fattening period and lung lesions at slaughter in swine

The examination of lung lesions on fattening pigs at slaughter is a useful tool for estimating the importance of respiratory diseases in a farm. The aim of this study was to evaluate the relationship between prevalence and extent of lung lesions at slaughter and the previous pig growth during the fattening period. Data were collected on near of 7000 pigs from 14 French farms, individually identified. weighed. and then scored at slaughter. Simple notation scales (0 to 28 for pneumonia, 0 to 2 for pleurisy), easy to apply during the slaughtering process, were used. At the farm level, there is a significant (p=0.008) negative correlation between prevalence of pneumonia and growth. At the individual level, there is a significant (p<10(-3)) negative correlation between pneumonia score and growth, with a weight gain loss of about 0.7% for each point of pneumonia increase. The pneumonia score is also significantly (p<10(-3)) linked with the age at slaughtering, especially for the high scores. The analysis also shows significant (p<10(-3)) differences for growth and age at slaughtering depending on the pleurisy scores.