Abstract

AMBROGI, Arnaldo et al. Postweaning Multisystemic Wasting Syndrome (PMWS) in pigs reared in an outdoor system in the farm in Argentina.. Rev Colom Cienc Pecua [online]. 2005, vol.18, n.3, pp.240-245. ISSN 0120-0690.

To carry out a clinical and pathological study in pigs reared in an outdoor system farm showing signs of wasting and witch then died between 40 and 90 days of life.The study was carried out between May, 2001 and February, 2002. Mortality was registered in animals in both weaning and postweaning periods. Sixteen animals with obvious signs of wasting were selected. Blood samples were extracted and necropsies were performed. Tissue samples were fixed in formaldehyde at 10%, stained with H/E and analyzed with inmunohistochemical techniques. Bacteriological, parasitological and viral studies were also carried out. Mortality was higher during first part of the period studied in weaning and postweaning. The animals that survived, showed decreased growth rate and weight loss, not being able to reach the same body size as their contemporaries. Clinical signs observed included growth retardation, weight loss, respiratory distiess and death. Necropsy revealed mucosal paleness, enlarged and brittle lymph nodes, pericardial and abdominal edema. Both bronchointerstitial and interstitial pulmonary pneumonia were observed in the lungs. The kidneys showed whitish areas in the renal cortex and renal pelvis edema. The lesions observed microscopically were: lymphoid depletion in lymph tissues, infiltration of histyocites, presence of giant cells, intracytoplasmic inclusion bodies, and focal necrosis. Giant cells, inclusion bodies and the macrophages of the follicular areas of the lymphoid tissues were inmunoreactive to the ABC technique in the presence of CVP2 monoclonal antibody. These findings confirm the presence of PMWS in pigs reared in an outdoor system farm. The animals showed clinical pathological symptoms similar to those described for animals in stall fed systems.

Keywords : circovirus; inclusion bodies; giant cells; lymph depletion; pigs; wasting.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )