Biological Characteristics And Isolated Of Canine Distemper Virus Of Fur-bearing Animals

During the period from June 2015 to June 2016,in mideastern Shandong Province,the s ubmission of 118 clinically suspected canine distemper virus infection in mink,raccoon and f ox's lungs are 83 parts,17 parts and 18 parts.According to Genbank published a highly cons erved region of canine distemper virus N gene design primers,to establish RT-PCR detection method,measured the number of positive diseases: 71,13 and 13,the positive rate was 85.54% 76.47% and 72.22%.In the positive samples,some samples were isolated by MDCK cell s.Four isolates of canine distemper were isolated from mink source samples.Raccoon source samples were isolated from a strain.Fox source samples were not isolated.The strains were n amed CDV103,CDV114,CDV122,CDVDH2 and CDVLC2.Positive samples were treated with some samples showed significant CPE and some samples without significant CPE.By th e cell freeze-thaw RT-PCR detection,no part of the CPE cell freeze-thaw was positive,the res ults show that CDV has different adaptability to MDCK cells.Analysis of Nucleotides and Amino Acid Sequences of Isolated Strains by DNAstar Soft ware.According to Genbank has been published as a reference strain,the genetic phylogeneti c tree was constructed and analyzed.H gene nucleotide sequence analysis results: The nucleot ide sequence analysis of H gene showed that the nucleotide sequence homology between the f ive isolated CDV strains was between 90.7% and 100.0%.The nucleotide homology of CDVL C2 strain and CDVDH2 strain was found to be 100.0%.Before the two with the other three st rains also have a relatively high nucleotide homology of 90.7%-91.1%.The potential N-linke d glycosylation sites of CDV103,CDV114 and CDV122 strains were found to have 9 sites,th e potential N-linked glycosylation sites between 309 to311 the are peculiar to wild strains.The majority of Asian-1 lineage has nine potential N-linked glycosylation sites.The potential N-li nked glycosylation sites of CDVDH2 and CDVLC2 strains were seven,which was the same a s the number of potential N-linked glycosylation sites of the H protein amino acid sequence of the foreign vaccine strain of Convac.Results of H gene phylogenetic analysis: CDV103,CD V114 and CDV122 belonged to Asia-1 lineage and had a close relationship with JN(08)(2009ChinaFJ810213fox).The isolates isolated from CDVDH2 and CDVLC2 belonged to the A merican-1 lineage and had a closerelatinshio with the Convac vaccine strain and the Onderste poort vaccine strain.The nucleotide sequence analysis of F gene showed that the nucleotide sequence of five iso lates was found to be 90.3%-100%.The nucleotide homology of the isolates of cDV103,CD V114 and CDV122 with the Onderstepoort vaccine strain was between 90.4% and 90.7%.The nucleotide homology of CDVDH2 and CDVLC2 strain with Onderstepoort vaccine was 99.0%.The amino acid sequences of the Fsp genes of CDV103,CDV114 and CDV122 contain t wo potential N-glycosylation sites at positions 62 and 108,the potential N-glycosylation sites being the same as the Asian-1 lineage.The five strains were located in two genotypes.CDV103,CDV114 and CDV122 isolates belonged to Asia-1 lineage,which was closely related to Z YL(2016ChinaKX499865fox).The isolates of CDVDH2 and CDVLC2 belonged to the Amer icas-1 lineage,and had a close relationship with the foreign Onderstepoort vaccine strains.The nucleotide sequence analysis of N gene showed that the nucleotide homology betwe en the five isolates was above 99.5% and the range was between 99.5% and 100.0%.CDV103 strain and CDV114 strain similarity up to 100.0%.The nucleotide homology of CDVLC2 str ain and CDVDH2 strain was 99.5%;N gene system analysis results:The five strains belonged to America-1 lineage and had a close relationship with derstepoort vaccine.In this study,we investigated the epidemiological investigation of canine distemper virus in Shandong province.RT-PCR was established.The positive samples were isolated from M DCK cells.The isolates were identified and genotypes were constructed.Mainly to overcome the difficult problem of canine distemper virus isolation,summed up the experience of canine distemper virus separation process.This study provides important molecular epidemiological data for the prevention and control of canine distemper virus.For the future canine distemper virus molecular biology research bedding.