The Pathological Diagnosis For The Clinical Case Of The Postweaning Multisystemic Wasting Syndrome In Weifang Area

The Postweaning Multisystemic Wasting Syndrome (PMWS) is associated with apathogenic porcine circovirus type 2(PCV-2)。PMWS affects nursery and early fatteningpigs mostly. Its clinical characteristics are that pigs show chronic wasting, weight loss, paleskin or yellow scour, diarrhoea, respiratory distress or laboured breathing, finally to death.PMWS was reported in many countries in the world since it was firstly reported in Canadain 1991.Recently,it brings great harm to the world pig farm due to its more and morepopular.Being greatly harmful to the pig feeding,the diease has become a focus for veterinaryresearch both in the world recently.Since it was reported and confirmed that PCV-2 waspopularly affected in pigherds in our country. The reports about PMWS in our native landare more and more recently. The disease was detected in Beijing, Tianjin, Guangdong,Shenzhen, Shanxi, Sichuan, Chongqing, Shanghai, Jiangsu, Zhejiang, Gansu and so on .PMWS is popular in our country now.Shandong is a big husbandry province,and Weifangis the city of husbandry-gathering most of Shandong.The number of pig husbandry ofWeifang is the first in Shandong,and now the biggest harm to pig husbandry is pigdiease.But the condition of the disease PMWS happening in Weifang is not reported. Thisstudy is to having a systematic pathological reseach to the PMWS-like pigs from four pigfarms,based on the lesons of Gross necropsy and etiological examination,to confirm thecondition of the disease PMWS happening in Weifang,and at the same time to give arefference of pathological diagnosis for the diagnosis of the PMWS-like pig for the pigfarms in Weifang district.1.Necropsy, etiological examition, histopathological observation were done to dozensof PMWS-like cases from four pig farms in Weifang district from the end ofNovember,2005 to February,2006.Results were that some characrestic lesions were foundin the tissues of the pigs; PCV-2 tested positive at the same time associated with PRRSV orActinobacillus pleuropneumoniae etal.These findings demonstrate that there werePMWS cases associated with PCV-2 and PRRSV or Actinobacillus pleuropneumoniae etalin Weifang district. 2. Histopathological examination revealed lymphocyte depletion, monocytes andmacrophages or eosinophil cells infiltration, syncytia and multinuclearmacrophages(langerhans-like cells) formation in the lyphoid tissues,numerouscytoplasmic inclusion badies in lymph nodes.Granulomatous lesions were apparent inlymphoid tissues.The characterristic lesions in lungs are interstitial and chronicmucopurulent bronchial pneumonia. The changes of hepatocytes necrosis hepatitis wasfound in the liver, and seen inflammatory cells and necrosic hepatocytes in the hepaticlobule. The histopathological lesion seen in these animals was mild multifocal interstitialnephritis lesons in the kidneys. Lesions of interstitial myocarditis includes mesangial cellsproliferation, mononuclear cells infiltration, multifocal necrosis of myocardialIt is indicated that PMWS associated with PCV-2 have existed in Weifang, and it is anow important epidemical disease that PMWS has seriously affected raiseing pigs.