Syngenta UK
Farminguk
25 September 2016 | Online since 2003
Less co2 Limited


25 April 2012 12:16:01 |Animal Health,Pigs,News

Swine infection screening using oral fluids


Large numbers of pigs could be screened more quickly and cost-effectively for a range of common pathogens, such as PRRSV, SIV and PCV2, thanks to a new PCR-based test system developed in the US.
The system uses samples of oral fluids which can be obtained quickly and easily by leaving a cotton rope in each pen for pigs to chew on. After 20 minutes or so, the rope can be retrieved and the saliva and gingival crevicular fluid squeezed into a sample bag and represents a pooled sample from the group.
Studies have demonstrated that oral fluid samples collected in this way can form the basis of a quick and cost-effective method for screening a range of common viral pathogens. The samples were tested using a commercially available sample preparation and real-time PCR test system which can isolate and identify viral nucleic acid in a matter of hours.
For PRRS, pooled samples of oral fluids were collected from groups of experimentally infected pigs using the rope technique, along with serum samples from each individual pig on the same days.
Both serum samples and oral fluids were processed using the same Applied Biosystems preparation system and real-time PCR test, both of which were supplied by Life Technologies.
The results showed that PRRSV nucleic acid was detectable in both serum and oral fluid samples from the day of infection through to 40 days after infection.
For PCV2, 24 pigs that were free of PRRSV and SIV were divided into 4 pens in separate rooms, and challenged with two different virus strains (PCV2a and PVC2b) at different times. One pen acted as a (non-challenged) control.
Oral fluids were collected regularly up to 140 days after initial challenge and tested using real-time PCR. High titres of PCV2 were detected from day 12 to day 28 post infection and virus was detectable throughout the entire testing period (days 2 to 98).
For SIV, a total of 180 spiked oral fluid samples were tested using real-time PCR, and subtyping reagents were also used to identify haemagglutinin and neuraminidase subtypes. The results showed that SIV nucleic acid was detectable in oral fluid samples spiked with high, medium and low copy numbers of SIV, and all positive samples could be successfully sub-typed.
"Collecting samples in this way is far less invasive for the pigs and so avoids unnecessary stress. And because all of the pigs will chew on the rope, it provides a very broad sample from the group, which is the key to assessing overall herd health," said Christina Boss, European Professional Service Veterinarian for Life Technologies. "In addition, if the pooled sample provides a positive result, then the animals in that pen can be tested individually to identify those that are infected."
"These results show that the simplicity of oral fluid sampling, combined with the speed and sensitivity of a PCR-based system, provides a practical and cost- effective way of monitoring large numbers of pigs for common virus pathogens."
The use of a semi-automated, PCR-based diagnostic system means that nucleic acid purification can be achieved in just 25 minutes and results from the real-time PCR available in 90 minutes. The molecular test is very specific and reliable, so the veterinarian can initiate individual testing as quickly as possible and make confident recommendations to the producer.
Screening for PRRS using samples of oral fluids has been gaining popularity over recent years because large numbers of pigs can be tested without increased cost or labour. The new research is due to be presented as a poster at the ESPHM meeting in Bruges in April.

Download

0 Comment

loginuserlogo
Name

Please enter your name


Email

Please enter your email

Please enter valid email


Comment

Please enter your comment


Post Comment

Your comment has been submitted successfully. Please wait for admin approval.


Comments

No comments posted yet. Be the first to post a comment


Ireland | 23 September 2016
Farmers who left safety net of EU subsidies to make fortune

Irish farmers have proved that they don't need subsidies from the EU to be massively successful in their chosen profession. Some have chosen to leave the payment safety net behind and seek their fortu...


China | 23 September 2016
China lays groundwork to be major producer of GMO crops

China has a fifth of the world’s population, but only about 7 percent of its arable land. Farming plus safe and healthy foods are national obsessions. So it came as no surprise that government-own...


USA | 23 September 2016
Drought grips parts of South, parches ground, withers crops

Extreme drought conditions are persisting in parts of Alabama and Georgia, wilting crops and raising the specter of wildfires. Thursday's U.S. Drought Monitor, a weekly report that tracks drought c...


China | 23 September 2016
China to reopen beef market to American producers after 13 years

American beef producers are expected get access to China for the first time in 13 years, raising the possibility that the U.S. could recapture lost market share in one of the fastest-growing global ma...


Australia | 23 September 2016
Greener pastures: the dairy farmers committed to sustainability

It was a soil bacteria course in New Zealand that convinced Reggie Davis to change his farming methods. The fourth-generation Victorian dairy farmer had become increasingly concerned by the costs, ...



Trending Now

Viewed
Discussed


Top stories you may have missed
FarmingUK
FarmingUK Logo

FarmingUK

A herd of rare White Park cattle could die out if its owners do not urgentl...


FarmingUK
FarmingUK Logo

FarmingUK

The UK government is "failing" to support farmers in the long-term accordin...


FarmingUK
FarmingUK Logo

FarmingUK

Retailer Co-op has announced that from May 2017 all of its bacon and lamb w...


FarmingUK
FarmingUK Logo

FarmingUK

Over 50 wildlife organisations have compiled a stock-take of all the UK's n...


FarmingUK
FarmingUK Logo

FarmingUK

In the run up to the EU farm ministers meeting the agricultural sector have...


FarmingUK
FarmingUK Logo

FarmingUK

The RPA must iron out a number of problems that still exist with 2015 BPS p...


FarmingUK
FarmingUK Logo

FarmingUK

Tourism businesses in the countryside are being held back due to the uncert...


FarmingUK
FarmingUK Logo

FarmingUK

A 24 point action plan aimed at revitalising Scotland's sheep sector after ...


FarmingUK
FarmingUK Logo

FarmingUK

A new survey has revealed that the vast majority of British consumers belie...


FarmingUK
FarmingUK Logo

FarmingUK

The British public are overwhelmingly in favour of keeping or strengthening...


closeicon
Username
Password