tailieunhanh - Báo cáo khoa học: "Advancing parity is associated with high milk production at the cost of body condition and increased periparturient disorders in dairy herds"

Tuyển tập các báo cáo nghiên cứu khoa học quốc tế về bệnh thú y đề tài: Advancing parity is associated with high milk production at the cost of body condition and increased periparturient disorders in dairy herds | J. Vet. Set. 2006 7 2 167-176 JOURNAL OF Veterinary Science Characterization of Chinook head salmon embryo phenotypes of infectious salmon anemia virus by real-time RT-PCR Khalid Munir Department of Pathology and Microbiology Atlantic Veterinary College University of Prince Edward Island 550 University Avenue Charlottetown PEI CIA 4P3 Canada We have previously described the development of a one-tube SYBR Green real-time RT-PCR assay for the detection and quantitation of infectious salmon anemia vứus ISAV in various biological samples. The twofold aim of the present study was to verify that the optimized SYBR Green real-time RT-PCR conditions could detect ISAV isolates of different geographic origins and to analyze the growth patterns of the selected ISAV isolates in the Chinook head salmon embryo CHSE -214 cells by this assay to better characterize their CHSE-phenotypes. A total of 24 ISAV isolates were used in this study. The results indicated that the SYBR Green real-time RT-PCR could detect ISAV of different geographic origins or laboratory sources. The capacity of ISAV isolates to cause cytopathic effects CPE in the Cl ISE-214 cell line viral titration of the infected CHSE-cell harvests and analysis of viral RNA levels in Cl ISE-214 cells at post-infection day zero 7 and 14 by SYBR Green real-time RT-PCR confirmed the existence of three CHSE-phenotypes of ISAV replicating cytopathic replicating non-cytopathic and non-replicating non-cytopathic. The identification of these three CHSE- phenotypes of ISAV has important implications from diagnostic and biological points of view. Key words CHSE-214 cell line infectious salmon anemia virus isolates SYBR Green real-time RT-PCR Introduction Infectious salmon anemia virus ISAV an economically important pathogen of farmed Atlantic salmon in the northern hemisphere is a type species under the new genus Isavirus within the family Orthomyxoviridae 1 21 42 Like the influenza A and B viruses IS AV particles are enveloped with