Diseases and agent | Age group affected | Nature of lesions | Signs, other lesions, comments |
Mycoplasmal polyserositis/arthritis Mycoplasma hyorhinis |
3-10 weeks. Occasionally in young adults. |
Swollen joints, serosanguinous or serofibrinous synovial fluid. Later, perhaps pannus and joint erosion. | Acute onset and lameness, fibrinous pericarditis, pleuritis, peritonitis singly or in combinations. Abdominal tenderness with sternal recumbency. Morbidity <25%, mortality usually low. |
Mycoplasmal arthritis Mycoplasma hyosynoviae |
8-24 weeks | Excessive serosanguinous joint fluid. Later, yellow membranes, perhaps pannus. | Stiffness, shifting lameness. Hind leg lameness common. Many slowly recover. Morbidity 1-50%, mortality low. |
Glasser’s disease |
Pigs from 2 weeks to 4 months old. Occasionally in young adults. | Swollen, painful, fluctuating joints with turbid fluid or green fibrin. Periarticular inflammation. | Classic lesions: serofibrinous or fibrinopurulent pleuritis, pericarditis and peritonitis or combination. Frequently meningitis and convulsions. Often affects best pigs. |
Streptococcal arthritis |
In weaners and growers up to market weight. | Acute suppurative polyarthritis. Meningitis common. | If meningitis, then CNS signs. Often fatal in weaners and growers. Can be epidemic with incidence up to 15%. Occasionally, valvular endocarditis. |
Streptococcal arthritis |
Suckling and postweaning pigs. | Hot swollen joints. Increased turbid synovia. Perhaps periarticular fibrosis, abscesses. | Accompanied by fever, depression and other evidence of septicemia. Endocarditis occasionally in older pigs. |
Erysipelothrix rhusiopathiae |
Young growing, weaned pigs. Also in finishers with acute erysipelas. | Growers: joint(s), especially hocks, knees, toes are swollen, painful; joint(s) decrease in size but remain enlarged. Finishers: limited swelling, severe pain. |
Growers: Number of swollen points in herd increases, often without an acute outbreak or much mortality. Finishers: Acute arthritis often a part of acute erysipelas. Identify erysipelas by culture of parenchymatous organs and acutely inflamed joints. |
Septic arthritis Other bacteria |
Neonates to piglets a few weeks old. | One or several painful, swollen joints. | Commonly caused by metastatic bacteria from infected navel, skin erosions/ulcerations at other sites. |
Key:
* Joints of knees, hocks, toes more visibly affected. Also examine shoulder, stifle, atlanto-occipital joints. Culture joints, parenchymatous organs.
CNS- central nervous system