Gold Nanoparticles Based Assay for Rapid Detection of Caseous Lymphadenitis in Sheep

Abstract

Corynebacterium pseudotuberculosis is responsible for Caseous Lymphadenitis (CLA) disease in small ruminants (goats and sheep). The disease is difficult to control because antibiotic therapy is not effective. The disease is characterized by caseous abscess formation in the internal and external lymph nodes. Diagnosis is currently achieved only by routine bacteriological culture of pus obtained from external abscess. The lateral flow immunochromatographic test (LFIT) was prepared and evaluated for discover the present of Corynebacterium pseudotuberculosis in pus samples obtained from abscess in superficial lymph nodes. The minimal count of bacterial that gave positive LFIT was 10 2 CFU/ 0.1ml. About 100 pus samples from external lymph nodes were examined by the LFIT and the results were compared with conventional microbiological method. The obtained results demonstrate that the specificity was calculated and found to be 88.24%, while sensitivity was 90.36% and finally the accuracy was 90% of LFIT as compared to conventional microbiological method. These findings indicate that the developed LFIT test is a fast, simple and inexpensive field test of good specificity, sensitivity and accuracy that can be used to enhance Caseous Lymphadenitis control among sheep and goats.

Preparation and evaluation of a lateral flow immunochromatographic nanogold diagnostic kit for brucellosis in sheep

“…The developed LFA strips could detect the Ab against Brucella in a serum sample at a minimal concentration relative to the Rose Bengal test, where the minimal amount of Ab against Brucella in the serum sample detected was 1.51.58 and 1.86 S/P in the LFA strips and Rose Bengal test, respectively; these lower cutoff values indicate a high sensitivity, which is one of the most important features of a good test [24]. In other studies on the detection of Corynebacterium pseudotuberculosis, the minimal concentration that gave positive results in LFIT was CFU/0.1 mL [25], while for, Staphylococcus aureus, the sensitivity was 106 CFU/0.1 mL [26]. For the evaluation of the specificity level, the standard antisera of Salmonella, E. coli, Mycoplasma, Pasteurella antisera, and positive Brucella were tested with the prepared kit.…”

Development of Lateral Flow Immunochromatographic Test for Rapid Detection of SARS-CoV-2 Virus Antigens in Clinical Specimens

“…The sample pad: Glass fiber (Ahlstrom 222), pretreated with sample pad buffer solution pH 8.5 (ultrapure water containing 1% (w/v) PVP, 2% (w/v) titronX100, 3.81% (w/v) borax 0.1% (w/v), 0.15% (w/v) SDS, casein sodium salt, 0.5% (w/v) sodium cholate and 0.02% (w/v) sodium azide) was dried at 37 °C. [ 19 ], as shown in Figure 1 .…”