PCR (polymerase chain reaction) identification method for porcine PRV (pseudorabies virus) variant strains

Abstract

The invention relates to the technical field of biological strain identification, in particular to a PCR (polymerase chain reaction) identification method for porcine PRV (pseudorabies virus) variant strains. The PCR identification method comprises steps as follows: DNA (deoxyribonucleic acid) of a to-be-identified virus is extracted for first-step amplification, a product with two bands amplified is a variant strain or an HB98 vaccine strain, and a product with one band amplified is a classical strain; DNA of the virus with the two bands amplified is subjected to second-step amplification, an amplification product with molecular weight of 293 bp is the variant strain, and an amplification product with molecular weight of 239 bp is the HB98 vaccine strain. The sensitivity of the first-step PCR can reach the virus amount of 2-20TCID50 or the plasmid amount of 0.5 ng / ml, and the sensitivity of the second-step PCR can reach the virus amount of 50TCID50 or the plasmid amount of 100 ng / ml. According to the sensitivity, whether PRV infection exists in a clinical pathological material can be effectively detected, classical strain infection or variant strain infection of the PRV are distinguished, and the accuracy rate is high.

Description

technical field [0001] The invention relates to the technical field of identification of biological strains, in particular to a PCR identification method for variant strains of porcine pseudorabies virus. Background technique [0002] Pseudorabies virus (Pseudorabies Virus, PRV) is a double-stranded DNA virus of the family Herpesviridae and the subfamily of Alphaherpesvirinae. The genome is about 140kd and encodes 69 open reading frames. The virus mainly causes abortion, stillbirth and respiratory symptoms in sows, and neurological symptoms and diarrhea in piglets, which has caused huge economic losses to the pig industry. At present, many countries in Europe and America have eradicated the disease through immunization and decontamination techniques. The disease has also been effectively controlled through the use of enhanced immunity and purification techniques in my country in the past ten years. However, at the end of 2011, the disease broke out again in pig farms immun...

AI Technical Summary

Problems solved by technology

Because the pig farms are immunized with vaccines such as Bartha-K61 at this stage, the national standard method is no longer suitable for identification, and the pseudorabies virus gE gene detection method for distinguishing vaccine virus from wild virus has been well applied, but due to pseudorabies The emergence of mutant strains of the virus has limited this method

This method cannot distinguish the variant strains from the classic strains, and the distinction between the variant strains and the classic strains is very important in immunity and monitoring, so a method that can effectively distinguish the classic strains of pseudorabies virus from the variant viruses is needed PCR diagnostic method

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