Isolation And Identification Of Riemerella Anatipestifer Of Shandong Province And The Co-infection Of Duck Circovirus

The Riemerella anatipestifer infection is a contagious infectious disease,which mainly aggrieve ducks,turkeys and wild birds.Sometimes,it is also named as New duck syndrome,Anatipetifer syndrome,Infectious serositis,Pasteurella anatipestifer infection and so on.This disease always bring inflammation to the heart,liver,ballonet,brain and faltopian tube.It is a major disease confronting the duck industry all over the world,and it usually brings lots of economic losses to the duck industry because of high mortality and loss of weight.Usually,using antibiotics correctly is an effective way to cure this disease,but the RA come into being resistance to various antibiotics easily and quickly,so it is very important to investigate the drug-sensitivity.In this research,19strains of Riemerella anatipestifer(RA) were isolated from liver and heart samples of sick ducks from Weifang, Taian, Linyi, Yantai, Qingdao, Jinan and other regions of Shandong Province in2009-2010.These isolates were identified by typical colony morphology and colony staining, and biochemical tests according the method of Edwards PR. PCR rapid detection with the specific primers based on the published sequence was uesd for further identification of the19isolates.Serotype of19isolates were identified by slide agglutination test, agar diffusion test and four of RA1type,15for the RA2type. The Cherry Valley Duck was challenged by the isolates for animals test, all duck died120h after challenged.The Dead duck showing pericarditis, inflammation airbags, liver enlargement and surface with a layer of film-like fibrin exudate, enlarged spleen,.All changes consistent with the clinical manifestations of Riemerella anatipestifer infection.We did the drug-sensitivity test to amikacin, chloramphenicol, gentamicin, neomycin, kanamycin, tetracycline, erythromycin, ampicillin, penicillin, streptomycin and other10kinds by Kirby-Baure method,and we find that the strains are sensitive to CMP、ERY、TET,resistant to KAN、AKN、P-G、NEO. The results showed that:Shandong regional duck anatipestifer tuberculosis drug resistance are very serious,Many strains isolated are resistant to more than six antibiotics. Especially the kanamycin, D amine kanamycin, penicillin, neomycin has a strong tolerance to the isolates. All subjects strains most sensitive to erythromycin and chloramphenicol, the largest inhibition zone diameters are up to36mm, all19isolates RA is not one pair of chloramphenicol-resistant, all sensitive. The Shandong region of multi-drug resistance is extremely serious, seven-resistant and eight largest proportion of resistant strains, up to78.9%of the total number of strains.A pair of primers of DuCV specific detection was synthesized according to literature,19DNA samples extracted from duck spleen and bursa of Fabricius and other organ positive for anatipestifer were amplified by PCR and PCR products approximately228bp were cloned and sequenced, eight DNA samples show DuCV positive. This study also shows the spread of epidemi of DuCV infection may be of an incentive of high morbidity and mortality induced by duck anatipestifer and other bacterial diseases from one side.