Development and clinical verification of a loop-mediated isothermal amplification method for detection of Salmonella species in suspect infected ducks

Abstract

To detect Salmonella spp. in suspect infected ducks, a loop-mediated isothermal amplification (LAMP) assay was developed. With the help of this assay, we can detect Salmonella enterica serovar Enteriditis and Salmonella enterica serovar Anatis above 6.0 cfu/test and 4.8 cfu/test, respectively, in pure-culture conditions, even in the existence of 0.01 g of duck liver or spleen homogenates; the detection thresholds were still achieved at 6.0 cfu per test tube. Further experiments of the test strains indicated the high specificity of this LAMP assay. In the detection of clinical specimens, a total of 115 Salmonella suspect infected clinical samples was analyzed by traditional culture method, LAMP, and PCR. The results suggested that 11 samples were positive by LAMP and culture methods; however, only 8 specimens were positive by PCR. In consideration of the high sensitivity and fast scanning speed of our LAMP method in clinical specimens, it was more suitable for field application and epidemiological investigation.

Rapid Detection of Salmonella spp. in Animal Origin Foods by In-House Developed Loop-Mediated Isothermal Amplification (LAMP) Assay

“…indicating that LAMP was 10 times more sensitive than PCR in their experiment. The findings are similar with Tang et al, (2012), Zhang et al, (2012) and Wang and Wang et al, (2013) who reported the sensitivity of LAMP assay 10 times higher than the PCR-based method. The results are also in accordance with Abdullah et al, (2014) who reported that LAMP method was highly specific and 10 times more sensitive in detecting S. typhi as compared to the optimized conventional PCR method.…”

Detection of Salmonella spp. by a loop-mediated isothermal amplification (LAMP) method targeting bcfD gene

“…; Tang et al . ), to our knowledge, this is the first report to directly detect Salmonella in the faecal samples free of pre‐enrichment.…”

“…While the established LAMP methods have been used to detect Salmonella in different food matrices (Hara-Kudo et al 2005;Okamura et al 2008;Li et al 2009;Ueda and Kuwabara 2009;Chen et al 2011;Tang et al 2012), to our knowledge, this is the first report to directly detect Salmonella in the faecal samples free of pre-enrichment.…”

Loop-mediated isothermal amplification assay for the detection of Salmonella spp. in pig feces

“…LAMP assay have been applied to eggs [2,14] and pork [19] to detect the Salmonella spp. The detection limit of Salmonella targeting rfbJ and fim Y was 10 3 CFU/mL in previous reports [15,18] which was lower than that of our LAMP assay. However, the reaction time was 60 min in a previous report [15], whereas the reaction time in this study was 30 min.…”