Studies On Epidemiology Investigation On Causes Of Avian Embryo's Death

The disease of avian embryo is refers to the chicken embryo's growth deviation, even the pathological change, abnormal and death in growth, as a result of certain unusual physics and chemistries and biotic factors. It can be divided into the hereditary embryopathy ,the trophism embryopathy ,the infectious embryopathy as well as the embryopathy caused by improper hatching condition. Among all, the infectious embryopathy has been most common, fatal to economy. Therefore this experiment systematically researched causes of the disease and the epidemiology investigation to provide the rationale of prevention and control of the disease of avian embryo. The research was divided into three parts:Part One: Studies on multiple PCR to detect E.coli, Salmonella bacillus and StaphylococcusAccording to the conservative gene which had been published on Genbank, three pairs of primers were designed to detect E.coli, Salmonella bacillus and Staphylococcus, carrying on the sensitive and specificity experiments. The specificity experiment indicated that the multiple PCR could only amplify corresponding specificity fragments of E.coli, Salmonella bacillus and Staphylococcus, but chain coccus and Haemophilus paragallinarum were negative. The sensitive experiment indicated that this method could detect 10ng E.coli, Salmonella bacillus and Staphylococcus and 100pg E.coli and Salmonella at least. Then this multiple PCR indicated that it was fit for the studies on the epidemiology investigation of E.coli, Salmonella bacillus and Staphylococcus which has good sensitivity and Specificity.Part Two: Studies on multiple PCR to detect REV, H9N2, CIAV and VAV According to the conservative gene which had been published on Genbank, four pairs of primers were designed to detect REV, VAV and H9N2 by multiple PCR. The specificity experiment indicated that it could only amplify corresponding virus, others were negative. The sensitive experiment indicated that the multiple PCR were positive when virus nucleic acid were diluted five times. The research showed that it was an accurate and quick detection methods which has good sensitivity and Specificity, and also a good way to detect REV, CAV, REO and H9N2.Part Three: Studies on epidemiology investigation on in ShanDongTo detect the reasons of avian embryo's death of large-scale broiler breeder farm by established multiple PCR, the results indicated that the detection rate of E.coli, Salmonella bacillus and mycoplasma in death embryo were separately 25%,4%,2.5%, the detection rate of Staphylococcus was 0.The detection of virus of broiler breeder indicated that H9N2,CAV,REV and REO were negative.