The forms of pleurisy located in the dorso-caudal region are primarily caused by Actinobacillus pleuropneumoniae (A.p.) and to a lesser extent by other pathogens.
A.p. is responsible for serious acute clinical disease characterized from a patho-anatomical standpoint by cases of fibrino-necrotic-haemorrhagic pleuropneumonia, with variable mortality in animals afflicted according to the virulence of the serotype involved.
Figure 2: Pig lungs - Cases of fribrous dorso-caudal pleurisy, likely associated with A.p.
The chronic form of the infection is characterized by the development of chronic lung lesions appearing as fibrous pleurisy of variable gravity at the dorso- caudal side of lungs that can seriously impair the animal’s productive career. This is because the dorsal pleural lesions, even more than the apical lesions, impose a mechanical limitation and a level of pain during the animals’ respiratory movements that result in reduced daily weight gain and an increased number of days necessary for reaching slaughter weight.
The chronic pleural lesions, still present at the time of slaughter, can be easily observed in this context and provide key information regarding the health conditions of the farm, the timeliness of undertaking control measures or for assessing the results obtained by implementing them.