Novel Multiplex Diagnostic Assays Development for Diagnosis of Porcine Respiratory Disease Complex02 April 2014
Researchers at South Dakota State University report a study representing the 'proof of concept' phase for a simple and cost-effective on-farm diagnostic test for Porcine Respiratory Disease Complex (PRDC).
PRDC is a significant economic problem for swine producers. PRDC outbreaks can cause elevated mortality, decreased feed efficiency, higher cull rates, increased days to market and increased treatment costs.
This syndrome is caused by the interaction of multifactorial aetiologies, including the participation of porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza virus (SIV) and porcine circovirus (PCV2) in the disease progression. In aid of PRDC prevention and control, producers and veterinarians desire multiplex tests that can readily detect multiple pathogens at the same time, in the same sample, and at a reasonable cost.
In this study, Ying Fang of South Dakota State University generated a panel of recombinant viral antigens and monoclonal antibodies (mAbs) for the diagnosis of PRRSV, SIV and PCV2 infections. Using these reagents, Fang and colleagues developed a multiplex fluorescent immunomicrosphere assay (FMIA) for detection of PRRSV, SIV and PCV2 simultaneously using serum or oral fluid samples.
Standard reagents and protocols have established through this study, and have been shared with major diagnostic laboratories and swine disease researchers.
Development of rapid, multiplex, cost-effective diagnostic tests will be important in population-based epidemiological studies, which provide important data on the early identification of susceptible groups in the population and evaluation of vaccination and herd management strategies.
These assays present advantages of simplicity, rapidity, cost-effectiveness and potentially increase the sample number of representative individual animals in a large population.
The dipstick test is user-friendly format, and can be performed on-site on a swine farm by untrained personnel.
It is expected that the dipstick test can be used as an on-site initial screening test to determine the disease status of a swine population in the field, and the multiplex FMIA will be used as a laboratory confirmation test for the accurate identification of various pathogens in PRDC.
Importantly, these tests are more suitable in the PRDC surveillance programme at a population level. Technologies developed in this study could apply to other swine pathogens, such as porcine respiratory coronavirus (PRCV), Mycoplasma hyopneumoniae (M. hyo.) and swine brucellosis.
Dr Fang added that the ultimate goal is to develop a rapid test to detect various swine pathogens simultaneously to help preventing and controlling of PRDC.
You can view the full report by clicking here.