Acute toxicity of five pesticides to Apis mellifera larvae reared in vitro          下载免费PDF全文

Pingli Dai  Cameron J Jack  Ashley N Mortensen  James D Ellis 《Pest management science》2017,73(11):2282-2286

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Viral wasting syndrome of swine: experimental reproduction of postweaning multisystemic wasting syndrome in gnotobiotic swine by coinfection with porcine circovirus 2 and porcine parvovirus   总被引：17，自引：0，他引：17  

Krakowka S  Ellis JA  Meehan B  Kennedy S  McNeilly F  Allan G 《Veterinary pathology》2000,37(3):254-263

One-day-old gnotobiotic piglets were inoculated intranasally with in vitro passaged porcine circovirus 1 (PCV-1), PCV-2, and porcine parvovirus (PPV) alone or in combination (PCV-1/PCV-2, PCV-1/PPV, and PCV-2/PPV). Piglets were evaluated for 1) the development of porcine postweaning multisystemic wasting syndrome (PMWS), 2) distribution of viral antigens by immunochemistry, and 3) viremia and the presence of viral DNA in nasal and ocular secretions and feces. All single agent-infected piglets and piglets infected with PCV-1/PCV-2 or PCV-1/PPV were clinically asymptomatic. They were transiently viremic and seroconverted to homologous virus(es). At termination of the study on postinfection day (PID) 35, microscopic lesions were restricted to focal inflammatory cell infiltrates in livers and myocardia. One piglet given PCV-1/PPV was PPV viremic for 2 weeks after infection and had lymphangiectasia of the spiral and descending colon associated with granulomatous inflammation. All four PCV-2/PPV-inoculated piglets developed PMWS, characterized by sudden onset of depression and anorexia, icterus, and submucosal edema. One piglet became moribund on PID 27, and the remaining three piglets were euthanatized between PID 27 and PID 30 because of severe disease. Lymph nodes were small and the livers were mottled. Disseminated angiocentric granulomatous inflammation was present in all tissues examined except the brain. Multiple lightly basophilic intracytoplasmic inclusion bodies were identified in macrophages and histiocytes. PCV-2 antigen was widely distributed within macrophages; PPV antigen was sparse. Hepatocellular necrosis and bile retention were prominent. PCV-2 DNA was identified in ocular, fecal, and nasal secretions. Terminal sera contained antibodies to PPV (4/4) and PCV-2 (3/ 4). Production of PMWS in gnotobiotic swine appears to require PCV-2 and additional infectious agents such as PPV for full disease expression in gnotobiotic piglets.  相似文献   

PMWS: experimental model and co-infections   总被引：12，自引：0，他引：12  

Allan GM  McNeilly F  Ellis J  Krakowka S  Botner A  McCullough K  Nauwynck H  Kennedy S  Meehan B  Charreyre C 《Veterinary microbiology》2004,98(2):165-168

Porcine circovirus type 2 (PCV2) is now recognised as the causal agent of porcine multisystemic wasting syndrome (PMWS), an economically important wasting disease of young pigs [J. Vet. Diagn. Invest. 12 (2000) 3]. Gross lesions of PMWS include generalised lymphadenopathy, hepatitis, nephritis and pneumonia and typical histological lesions include lymphocytic depletion and multinucleated giant cell formation in lymph nodes, degeneration and necrosis of hepatocytes, and multifocal lymphohistocytic interstitial pneumonia.This communication will review the results of experimental infections of gnotobiotic (GN), colostrum-deprived (CD) and colostrum-fed (CF) pigs within our group, and elsewhere, with PCV2 and the conclusions that can be drawn from this work.  相似文献