August 23, 2018

US livestock farmers told imported feed ingredients could be carriers of viruses

The US livestock herds face the risk of getting infected by foreign animal diseases via imported feed ingredients.

The recent summer conference of the Academy of Veterinary Consultants (AVC) suggested more emphasis on feed biosecurity to help reduce this risk, Drovers reports.

In the conference, Dr. Scott Dee, director of research of Pipestone Veterinary Services in Minnesota, summarised his company's research on survival of viral pathogens in feed ingredients.

In their study, Dee and his colleagues tested the survivability of several viruses in a variety of feed ingredients. They inoculated feed samples with the viruses and stored the samples in environmental chambers simulating the actual time and conditions for feed shipping across common Pacific and Atlantic routes such as from Beijing or Warsaw to Des Moines, Iowa.

As per the Drovers report, the researchers found that some viruses remained very stable in certain feeds through the simulated shipping process. The researchers used Seneca virus as a surrogate for FMDV (foot and mouth disease virus) because of federal restrictions. They found that Seneca virus survived in most feeds and that the African swine fever virus survived well in soy meal.

However, some other viral pathogens such as PRRSV (porcine reproductive and respiratory syndrome virus), BHV (bovine herpesvirus) and BVDV (bovine viral diarrhea virus) did not survive well in feeds.

Previous research also demonstrated that PEDV (porcine epidemic diarrhea virus) could survive in feed. 

Dee said that there was a need for more research in this area and more screening of imported feed ingredients. He added that research should include testing actual shipments of imported feeds to determine whether virus survival trends resemble those found in the simulations.