ND Virus Antigens Shed In Chicken Flocks Immunized With Live ND Vaccines

The NDV strains were multiplied in 9 days SPF chicken embryos respectively and the viruses were purified by plaque formation and sucrose density gradient centrifugation and the genomic RNA was extracted respectively.After the agarose gel electrophoresis,recovery and purification,the genome cDNA of virus were diluted 1:1,1:2,1:4,1:8,1:16,1:32 by 0.9% Nacl. Then PCR the gene and make sure the sensitivity of the detection. The resurts shows that that the nucleotide the gene is 686bp long encoding a protein of 228 amino acids respectively, which is the same as the designed before,the negative contrast have no nucleic acid straps. Attenuated the genome cDNA ,and then multiproportive attenuated follow the former way. The supersensitivity of cDNA can reach about 23 multiproportive attenuated.After immunized with ND live vaccines,the chicken of differenct immune groups were detected of NDV antigens in cloaca swabs and breast meats by virus isolation and identification. Collect baenosome muscle 25-30g of the tissue sample,put them into the sample pocket.After sample were dealed, inoculated them to separate the virus,and then collected allantoic fluid to do some HA and HI...