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African swine fever virus (ASFV) is a highly pathogenic and rapidly disseminated virus with strong viability in the environment, suggesting the importance of environmental detection for prevention and control in all the pig industry. However, the detection results of environmental swabs cannot always reflect the accurate status of viral pollution, leading to persistent ASFV environmental contamination. In this study, we developed an ASFV eluant with higher environmental ASFV detection efficiency relative to 0.85% saline solution, which obtains the patent certificate issued by the China Intellectual Property Office (patent number:202010976050.9). qPCR analysis showed that in the environmental swab samples, the number of viral copies was 100 times higher for the ASFV eluant treatment than the traditional eluant treatment (0.85% saline solution). And besides, the high sensitivity of the ASFV eluant had be verified in a slaughterhouse environmental sampling detection. In soil samples, the ASFV eluent showed the same extraction effect as the TIANamp Soil DNA Kit, in contrast to no extraction effect for 0.85% saline solution. Simultaneously, this eluent could protect ASFV from degradation and allow the transportation of samples at ambient temperature without refrigeration. In clinical practice, we monitored the environmental contamination condition of the ASFV in a large-scale pig farm. The results shown that the ASFV load decreased after every disinfection in environment. This study provides an effective solution for surveilling the potential threat of ASFV in environment. Key points: The ASFV eluant can significantly improve the positive detection rate in environmental samples in clinical practice. The ASFV eluant is economical and convenient compared to commercial kit.. The ASFV eluant can provide a caution for the environmental safety for China's pig industries, slaughter houses, and transportations and facilitate ASFV eradication. [ABSTRACT FROM AUTHOR]

[Display omitted] • The erosion resistance of magnesium phosphate cement slurry to a solution mimicking saline soil was studied. • Resistance to saline soil erosion was evaluated by measuring the cement's macro-mechanical properties. • The mechanism of resistance to saline soil erosion was studied by microstructural analysis. The durability of concrete structures is affected by dry-wet and freeze–thaw cycling, and erosion by saline soils, such as those common to western China. In this study, the anti-erosion properties of magnesium phosphate cement paste (MPC) in salinized soil were investigated. The influences of the magnesium-to-phosphorus ratio (M/P), water-to-cement ratio (W/C), borax-to-magnesium ratio (B/M) and fly ash admixtures were studied in MPC specimens subjected to dry-wet cycle tests in water and saline solutions, with naturally cured specimens used as controls. The compressive strength of MPC was analysed by range analysis, analysis of variance and factor index analysis under various numbers of dry-wet cycles. Mass losses were quantified, morphologies were observed, and X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TG-DSC) were used to assess MPC before and after erosion. It was found that M/P and B/M were the major influences on the compressive strength of MPC. In MPC under natural curing, M/P was a strong influence on strength, while in MPC in water and saline solution, B/M was more important. The MPC slurry was most resistant to saline soil erosion with a 20% fly ash admixture, M/P = 2.5, borax admixture = 0.09 and water-cement ratio = 0.17. After dry-wet cycling, the MPC's mass in water gradually decreased while that in saline solution gradually increased. With 40% fly ash, the compressive strength corrosion resistance coefficient of MPC placed in saline solution for 180 dry-wet cycles was 78.28%, indicating that a moderate amount of fly ash can enhance the saline soil anti-erosion performance of MPC. According to TG-DSC and XRD analyses, when MPC was subject to dry-wet cycling in water, the content of MgKPO 4 ·6H 2 O(MKP) was the highest. The content was lower under natural curing and lowest in the saline solution. According to SEM, the degree of hydration of MPC was higher under dry-wet cycling than under natural curing, but the crystal structure of MKP was loosely arranged, which reduced the strength of the MPC. [ABSTRACT FROM AUTHOR]