The Detection Of Porcine Parvovirus And Streptococcus From Pig Farm Soil And Screening Of The Disinfectant

With the fast development of our country's stock raising, especially the intensivism breeding, the pollution problem of soil environment around the breeding farm is getting more and more attention. So we create a method of choosing the porcine porvovirus (PPV) and the porcine streptococcus (S.suis) as two index to evaluate the soil environment pollution extent by inspecting those two bacteria in the soil, then we choose a optimal disinfector by the method to effectively control the soil pollution aroud farm.1. The establishment and application of the method of inspecting PPVChoosed the VP2 gene segment of PPV as the target gene and designed 4 primers to recognize 6 specific position of the destination gene segment with the software of LAMP primer-designing, We found no unspecific-amplification reaction by LAMP amplification reaction of usual bacteria in the soil, meaning that this was a specific method. The sensitivity was 0.002 TCID50, it was about 10 times sensitive than PCR. We inspected 92 samples collected from 18 breeding farm in Hubei province, the 14 samples were positive by LAMP and 10 by PCR,indicating that the LAMP is a high specific, sensitive, fast and convenient inspecting method.2. The establishment and application of the inspecting method of the S.suisBy choosing the GDH gene segment of S.suis as the target and using PCR, we inspected 21 positive samples from 92 samples collected from 18 breeding farm in Hubei province, the positive rate is 22.83%.Simultaneously we filtrated the culture medium of S.suis. By the difference of each antibiotic's MIC90 to S.suis and their anti bacteria spectrum we choose Polymyxin B Sulfate B, acheomycin, Sulfamonomethoxine as the antibiotic additive of culture medium, the concentration of each additive was 30μg/mL,15μg/mL,15μg/mL. The growth rate of the S.suis in such culture medium was 94.1%, indicating that it was suitable to separate the S.suis from soil.3. The sterilization function of disinfector to the soil S.suis in this experimentWe test Yi lv xiao, Glutaraldehyde, An bi sha and Tian ran jing to evaluate their sterilization effection to the soil S.suis, following is the result:diluent:optimal diluent is 0.1%Tween80/PBS.Neutralization liquid:An bi sha:0.5% Na2S2O3+l% lecithin+1% Tween80/PBS.Yi lv xiao:0.5% Na2S2O3+l% Tween80/PBS; Glutaraldehyde:1% glycin+1% lecithin+1% Tween 80/PBS.Soil carrier test:Yi lv xiao including Chlorine dioxide (100mg/L) sterilizing for 1 h or 0.1% Glutaraldehyde for 10 min could kill 100% S.suis,indicating that the Yi lv xiao and Glutaraldehyde were more effective,and An bi sha must sterilize for 30 min in high concentration(2000mg/L), but Tian ran jing had no sterilization function to S.suis. So we choose Yi lv xiao and Glutaraldehyde as the disinfector in later field experiment.Field experiment result showed that the sterilization rate to S.suis was 100% by using Yi lv xiao including Chlorine dioxide(600mg/L) or 0.1% Glutaraldehyde for 24 h and 48 h, that could effectively control the pollution of S.suis to the soil.Our research set up the detection method of PPV and S.suis in soil, which supply theory bases for the future desease prevention and control, and filtrated disinfector of S.suis in soil of around breeding farm, controlled the contamination of soil, prevented pervasion of the pathogeny.