Through the years, salmonella, campylobacter, and avian influenza have resulted in sick days for consumers and loss for poultry and food producers. Although the authorities have increased the requirements for producers and increased controls over the years, it is difficult to avoid contamination altogether.
Soon, the pathogenic microorganisms can be detected faster than ever before. A newly developed device called Vetpod reduces the response time on samples collected in poultry or fresh meat production. It normally takes up to a couple of days to find out if the poultry is infected, as the samples must be taken to a laboratory, cultivated, and analysed. With Vetpod, it only takes 30-60 minutes. Vetpod was developed by DTU in the Vivaldi research project which is a collaboration with several European partners, including the Swedish veterinary institute, the University of Parma, and a number of companies.
As the device is so small that it can be held with one hand, all aspects of testing for infectious diseases can be done onsite at the poultry and food producer, enabling quick identification of any problems, explains Mogens Madsen, Senior Executive Officer at DTU Bioengineering.
“The project is driven by a constant demand for increased speed in food production from farm to table. It’s about avoiding disease in humans and not harming animal production. There’s thus a great need for rapid methods that can detect any problems before the food goes out to consumers,” says Mogens Madsen.
Speed is crucial
The EU currently has salmonella monitoring programmes for the production of broiler chickens. Approximately two weeks before the animals are slaughtered, local authorities take samples in each flock and send the samples for laboratory analyses. This is implemented throughout the EU and has reduced the risk of infection. In Scandinavia, the authorities also take random samples of finished food products before they are sent to consumers. Here, speed is also crucial, as the producers must withhold the products until they know if the food is free of salmonella. Nevertheless, pathogenic bacteria can escape through chicken production, which amounts to hundreds of millions of chickens in the EU, says Mogens Madsen.
“There have been plenty of cases involving salmonella, which were unfortunately not detected until consumers got sick. It’s in the interest of both society and businesses that we prevent that. The sooner we know whether there are infectious microbes in a flock or in the finished product, the sooner the producers can react and prevent the infection from spreading,” he says.
Lab-on-a-chip
The device was developed in a project headed by Professor Anders Wolff from DTU Bioengineering, in close collaboration with Professor Dang Duong Bang from DTU Food. With the help of a specially designed chip that was also developed and produced in the clean room at DTU, the device can examine whether samples taken from the animals’ throat or rectum are infected with unwanted microorganisms.
“Vetpod can quickly detect viruses and bacteria based on their genetic material. We use a familiar method that we’ve made much simpler and more user-friendly,” says Anders Wolff.
The method referred to by the Professor is called loop-mediated isothermal amplification (LAMP). With LAMP, you can multiply the genetic material of the microorganisms. In a Vetpod test, samples from the animals are placed in what looks like small holes in the chip. These holes contain different reagents and enzymes in dry form. When the chip is inserted in the device, the samples are heated to 65°C. This causes a reaction where a specific piece of the microorganisms’ genetic material is copied. The reaction forms a by-product called pyrophosphate, which in turn reacts with magnesium ions that make the liquid in the sample cloudy. This means that if the sample is contaminated, there will be less light coming through it. The result can be read on a display after 30-60 minutes.
“When the samples are positive, the DNA code can then be analysed in detail in a laboratory to find possible routes of transmission and infection risks. That’s why Vetpod is a tool for screening,” says Anders Wolff. Mogens Madsen continues: “A great many samples are taken out there to monitor the health of the animals in general or in connection with outbreaks.
This overloads the laboratories because the samples just keep coming in. With Vetpod, you can quickly find out if there’s a problem and concentrate the effort. That’s the great value of the project,” says the Senior Executive Consultant.
Close to commercialization
The researchers have ensured that all the components of the Vetpod are standard components, so the device itself is easy to put into production. They are already in dialogue with the biotech company DNA Diagnostic in Risskov, Aarhus, Denmark, which specializes in testing systems for the poultry industry. The company sees a market for Vetpod, according to Jogvan Houmann, Chief Sales Officer in DNA Diagnostic.
“The potential is really good. There’s definitely a market for the product and it should be successful. Vetpod can be used locally, which is what many producers need,” says Jogvan Houmann, who goes on to explain that while the industry’s major producers often have well-functioning and established systems for control, Vetpod can play a key role for small and medium-sized producers especially, where a portable device is a clear advantage.
Over the coming year, Vetpod will undergo validation, the purpose of which is to prove that the new technology is at least as good at detecting viruses and bacteria as the conventional methods.
“The preliminary tests show that Vetpod is just as precise and sensitive as existing methods. Our solution is just much faster, so it’s going well,” says Anders Wolff.
Vetpod so far detects salmonella, campylobacter, and avian influenza, but the solution is generic and can therefore be further developed to test for other bacteria such as E. coli or listeria.