A Canadian study has found that it is possible to produce piglets, negative for Porcine Respiratory Coronavirus (PRCv), from a PRCv-positive farrow-to-finish herd. This was achieved through early weaning and segregation.
The research was published in this summer's edition of the Journal of Swine Health and Production, published by the American Association of Swine Veterinarians (AASV).
PRCv is variant of TGEv
In their article, the researchers describe Porcine Respiratory Coronavirus (PRCv) as 'a variant of transmissible gastroenteritis virus (TGEv)'. "Porcine respiratory coronavirus colonises the respiratory tract of swine, as opposed to TGEv, which selectively infects and replicates in enterocytes in the small intestine. [...] Pigs are infected by direct contact or airborne transmission. Swine population density, season, and swine-farm proximity influence the transmission and epidemiology of PRCv."
The researchers point out that the virus is endemic in North America and that a negative status for PRCv is required by certain countries wishing to import swine from North America.
Producing PRCv-negative piglets
The researchers conducted a study to determine if PRCv-negative piglets could be produced from PRCv-positive sows by early weaning and removal off-site for rearing.
A 250-sow herd located in southwestern Ontario, Canada, was selected for the purpose of this study, which mostly took place in 2010. In total, 40 piglets were early weaned from a PRCv-positive sow herd and tested monthly for PRCv antibodies and virus for a total of four months. While some piglets tested positive for PRCv at the beginning of the study, all pigs tested negative at the end of the study, the researchers write.
Demonstrating a method for pig exporting
The researchers conclude that the study demonstrates a method by which PRCv-negative animals may be attained for the purposes of export to countries requiring PRCv-negative status.
The research was carried out by Dr Sue Burlatschenko and Dr Christa Arsenault. Burlatschenko is attached to Goshen Ridge Veterinary Services, Tillsonburg, ON, Canada. Arsenault was attached to the Canadian Food Inspection Agency, Mitchell, ON, Canada; she is currently with the Ontario Ministry of Agriculture, Food and Rural Affairs, Guelph, ON, Canada.