Today, we are sharing a new article from the Corzo lab, published in Porcine Health Management earlier this month. This study looks at the number of weeks it takes for processing fluids to become negative after a Senecavirus A outbreak. The full article is available on the journal’s website in open access.
Methods
- 10 breed-to-wean farms experiencing a Senecavirus A outbreak
- Processing fluids were collected for up to 50 litters per sampling event
- Sampling occurred bi-weekly for the first 4 months after detection of the outbreak. After that, sampling was done monthly until the end of month 6.
- Samples were tested by Rt-PCR.
Results
- 310 samples were tested across the 10 farms.
- Farms 1 and 2 had an average of 4.3 and 2.1 samples per tested week, while all others had only one tested sample per week.
- Processing fluids were found positive up to three weeks before the detection of vesicles by the farm staff.
- Processing fluids were found positive from 1 week to 21 weeks post outbreak (mean=11.8 ; 95% CI– 8.1, 15.5).
- Production parameters remained constant in all farms for which data was available.
Abstract
Senecavirus A (SVA) causes vesicular disease in swine and has been responsible for a rampant increase in the yearly number of foreign animal disease investigations conducted in the United States. Diagnostic investigations for SVA are typically performed by sampling animals individually, which is labor-intensive and stressful. Developing an alternative aggregate sampling method would facilitate the detection of this virus at the population level. In a preliminary study, SVA was detected in processing fluids (PF) collected in a breeding herd before and after outbreak detection. The objective of this study was to estimate the average number of weeks PF remain SVA-positive after an SVA outbreak. Ten farrow-to-wean breeding herds volunteered to participate in this studyby longitudinally collecting PF samples after an SVA outbreak was detected and submitting samples for RT-rtPCR testing. The PF samples from the 10 farms were SVA-positive for an average of 11.8 weeks after the outbreak. Here, we show that testing of PF may be a cost-effective method to detect SVA and help halt its spread in SVA-endemic regions.