Feed or feed transport as the potential route for a porcine epidemic
diarrhea outbreak in a 10,000-sow breeding herd in Mexico
Abstract
Porcine epidemic diarrhea virus (PEDV) produces infection in pigs
characterized by vomiting and diarrhea. PEDV is transmitted via
oral-fecal and a very low oral dose is enough to infect susceptible
pigs, causing devastating consequences in production. A 10,000-sow
farrow-to-wean farm located in northwest Mexico was infected with PEDV.
After the observation of the first clinical signs, an outbreak
investigation take into place to determine the most probably source of
infection. A systematic collection of samples including rectal swabs,
gestation and lactation feed, surface swabs from the interior or feed
bins and many points of the feed truck delivering the implicated feed
was performed. Samples were tested for PEDV polymerase chain reaction
(PCR). Positive PCR results showed the evidence of PEDV RNA in lactating
feed, the interior walls of the feed bins and in the interior of the
auger boom of the feed truck. This, connected with the location of first
clinical signs point that the most probably incursion of PEDV in to this
breeding herd was contaminated feed. This paper shows how feed or feed
transport can be a potential source of PEDV infection in farms and
highlight the importance of stablishing biosecurity programs to mitigate
the risk of PEDV infections.