Everybody knew that it would happen sooner or later. Still the news that Germany was hit with ASF on the 9th of September shocked the whole industry. What we knew already from the recent Covid outbreak in humans is reconfirmed for ASF: Viruses don’t stop at borders. If we look back to the moment ASF entered the European continent in 2008 in Moldavia via infected meat from Africa we can conclude that until today the virus is spreading in Europe at a constant pace of a few 100 km per year, and it seems very hard to stop this. But how is the virus spreading and what can we do to stay safe from it?
Viral vectors and their importance
Animals
When thinking of animals that can transport the virus, the first ones that pop up are of course wild boars. It is proven that these animals spread the disease easily but it is also known that the territory of a wild boar is only about 15-20 km diameter. Recent outbreaks (also in Europe) are sometimes seen much further away in which case we have to look at other possible vectors. Next to wild boars it is proven that also flies and ticks can spread the virus. Not much research has been done on birds but in Asia there is a strong belief that crows would be spreading the disease as well when coming in contact with corpses of infected animals.
Humans
After animals, the main threat for spreading viruses are human. Big industrial farms try to keep biosecurity levels at the highest possible standard. However they have to rely on their staff. Industrial farm workers very often have pigs at home and here the level of biosecurity in barns is lower, meaning that the chances of getting infected are higher, especially when applying swill feeding.. In Asia the workers often travel long distances, possibly causing a very fast spreading of this disease across Asia.
Feed: the forgotten vector
There is no doubt that animals and humans are the biggest spreaders of ASF. However there are other pathways that should be considered when defining a strategy to keep a farm virus-free. Feed is an additional entrance gate that gets increasing attention when talking about biosecurity, as it is never produced completely on the pig farm.
Is it theoretically possible, from a scientific point of view, that African Swine Fever and other viruses are being spread from the field to the animals? The answer is YES! Recent research at K-State University proved that African swine fever can survive several months in animal feed. It can even survive conditions of high humidity and temperature (Nierderwerder et al.., 2019). Certain frequently used raw materials like soy bean meal or DDGS will even create favorable conditions for viruses to survive and this way extend their half lifetime up to 180 days (Dee et al., 2019). Next to this it was also reported that the infection dose needed in feed and water is very low.
Is this theory confirmed in practice? The answer is again YES! By interrogating over 655 farms in Romania, from which 200 were infected by ASF, scientists determined the factors that increase the risk of getting infected. Feeding cereals from infected areas appeared to be strongly correlated with the chance of being infected. This study was recently published in Nature (Bocklund et al., 2020) and is confirming previous studies performed in Estonia (Nurmoja et al., 2018) with similar conclusions.
In conclusion, securing feed is one of the protection measure that cannot be ignored in fighting against ASF speading.
A natural solution that respects viability of pig farms
Feed: the forgotten vector
To fill the need for an improved global biosecurity of the feed, Agrimprove recently developed FeedLock®. FeedLock® is a patented mixture of medium chain fatty acids (MCFA) with proven inhibiting effect on viral transmission via the feed. Independent research facilities in the US and Vietnam have proven the effects as well in vitro as with in vivo bio assay. FeedLock® is able to neutralize viruses in infected feed and this way safeguard the animal from being infected through this pathway. In that respect, a study was performed at the National Institute of Veterinary Research in Vietnam to test the efficacy of FeedLock towards ASF. In this in vitro study several prototypes were tested for their abilities to reduce the initial virus load in feed. Quantification by real-time PCR proved that FeedLock® reduces the risk of viral contamination 28-fold even at low concentrations.
Safety and profitability go hand in hand
Reducing viral transmission is the focus point of FeedLock®. However, since it is based on MCFA, other benefits will also be granted once the supplemented feed will be ingested by the pigs. Reduced bacterial load and increased performance in the animals are proven effects of Agrimprove MCFA blends. This way farmers receive a nice economical return when adding FeedLock® to their biosecurity strategy.
Biosecurity on farm level is currently the only possibility for farms to protect themselves against diseases like ASF and feed represents for the virus a gate that cannot be simply closed. These extra measures might lead to additional costs but will lead at the same time to wide additional benefits. Since only limited amount of viral particles are needed to cause an infection with a disastrous result, it is of utmost importance to close all gates. FeedLock® gives the unique opportunity to close also the last gate without adding additional costs or losing performance.
