Detection of Foot-and-Mouth Disease Virus in Swine Meat Juice

Abstract

Foot-and-mouth disease virus (FMDV) is a highly contagious agent that impacts livestock industries worldwide, leading to significant financial loss. Its impact can be avoided or minimized if the virus is detected early. FMDV detection relies on vesicular fluid, epithelial tags, swabs, serum, and other sample types from live animals. These samples might not always be available, necessitating the use of alternative sample types. Meat juice (MJ), collected after freeze-thaw cycles of skeletal muscle, is a potential sample type for FMDV detection, especially when meat is illegally imported. We have performed experiments to evaluate the suitability of MJ for FMDV detection. MJ was collected from pigs that were experimentally infected with FMDV. Ribonucleic acid (RNA) was extracted from MJ, sera, oral swabs, and lymph nodes from the same animals and tested for FMDV by real-time reverse transcription polymerase chain reaction (rRT-PCR). MJ was also tested for FMDV antigen by Lateral Flow Immunoassay (LFI). FMDV RNA was detected in MJ by rRT-PCR starting at one day post infection (DPI) and as late as 21 DPI. In contrast, FMDV RNA was detected in sera at 1–7 DPI. Antigen was also detected in MJ at 1–9 DPI by LFI. Live virus was not isolated directly from MJ, but was recovered from the viral genome by transfection into susceptible cells. The data show that MJ is a good sample type for FMDV detection.

Development of reverse-transcriptase, real-time PCR assays to distinguish the Southern African Territories (SAT) serotypes 1 and 3 and topotype VII of SAT2 of Foot-and-Mouth Disease Virus

“…All negative samples were defined as such by no amplification produced when tested by the FMDV 3D pan-serotype rRT-PCR but also the presence of a quality template by producing a Cq ≤ 35.99 on the Xeno rRT-PCR assay. Eighteen remnant clinical samples ( 42 ) and two mock viral infections were evaluated. These samples included five tissue sample homogenates (porcine lymph node, porcine tongue and three bovine tongue tissues from different animals), five porcine serum samples, four porcine oral swab samples, four porcine oral fluid samples and BHK-21 cell culture supernatant collected from PBS mock viral infections collected two and three DPI.…”

“…Evaluation of the SAT1, SAT3 and SAT2 topotype VII rRT-PCR assay diagnostic specificity was performed using samples that were confirmed to be true negatives by the FMDV 3D pan-serotype rRT-PCR. The samples were remnant negative samples obtained from previous animal experiments conducted in the laboratory ( 42 ). The samples included five tissue sample homogenates (porcine lymph node, porcine tongue and three bovine tongue tissues from different animals), five porcine serum samples, four porcine oral fluids samples, four porcine oral fluid samples and BHK-21 cell culture supernatant collected from PBS mock viral infections collected two and three DPI.…”

Advances in the differential molecular diagnosis of vesicular disease pathogens in swine

“…The sample content determination does not need to open the reaction tube, and can be analyzed by the fluorescence signal intensity generated during the qRT-PCR amplification process, avoiding cross-contamination between samples ( Galluzzi et al, 2018 ). qRT-PCR has the advantages of rapidity and sensitivity, and is suitable for different clinical sample types including swabs, sera, vesicular fluid, milk and tissue samples ( Burkhalter and Savage, 2017 ; Fontel et al, 2019 ; Yeo et al, 2020 ; Armson et al, 2020a ). At present, Real-Time PCR is a commonly used method to detect the pathogens of animal diseases.…”

“…Armson et al determined the utility of testing pooled milk by rRT-PCR as an alternative approach for FMD surveillance, and proved that pooled milk has potential value as a surveillance sample to reveal subclinical FMD infection ( Armson et al, 2020a , b ). Yeo et al amplified the FMDV genomic sequence in meat juice using qRT-PCR and confirmed the presence of FMDV RNA ( Yeo et al, 2020 ). The discovery indicated that meat juice can be used as a good sample type for FMDV detection and play a role in the import and export quarantine of meat products ( Yeo et al, 2020 ).…”

Meat Exudate for Detection of African Swine Fever Virus Genomic Material and Anti-ASFV Antibodies

“…The potential use of meat exudate for the detection of transboundary and endemic diseases has been explored previously. Genomic RNA of classical swine fever virus (CSFV) and foot and mouth disease virus (FMDV) have been successfully detected in meat exudate [ 34 , 35 , 36 ]. Meat exudate has also been used successfully employed for antibody-based serosurveillance of several other viral (influenza A virus, porcine circovirus 2, Aujeszky’s disease, porcine epidemic diarrhea virus, porcine reproductive and respiratory syndrome virus), bacterial ( Salmonella spp., Mycoplasma hyopneumoniae , and Yersinia enterocolitica ), and protozoal ( Trichinella spp.…”