PCR primer and method for identifying swine pseudorabies virus variants

Abstract

The invention relates to the technical field of identification on biological virus strains and particularly discloses a PCR primer and method for identifying a swine pseudorabies virus variant. The method comprises the steps: viral DNAs to be identified are extracted, first-step amplification is carried out by employing the primer designed by the invention, viral DNAs with two amplified straps arevariants or HB98 vaccine virus strains, and viral DNAs with one amplified strap are classical virus strains; and the viral DNAs with two amplified straps are then subjected to second-step amplification, amplification products with the molecular weight of 211bp are the variants, and amplification products with the molecular weight of 293bp are the HB98 vaccine virus strains. The sensitivity of first-step PCR can reach the viral load of 10TCID50 or the plasmid amount of 0.01 ng / ml, and the sensitivity of second-step PCR can reach the viral load of 10TCID50 or the plasmid amount of 0.1 ng / ml. The sensitivity can be used for effectively detecting whether pseudorabies virus infections are present in clinical cases or not and distinguishing pseudorabies virus classical virus strain infections from variant infections, and the accuracy is high.

Description

technical field [0001] The invention relates to the technical field of identification of biological strains, in particular to PCR primers and a detection method for identifying variant strains of porcine pseudorabies virus. Background technique [0002] Pseudorabies virus (Pseudorabies Virus, PRV) is a double-stranded DNA virus of the Herpesviridae family and Alphaherpesvirinae subfamily. 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...

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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