Submitted to: International Symposium on Epidemiology and Control of Salmonella in Pork
Publication Type: Proceedings
Publication Acceptance Date: 4/16/1997
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: The effect of infection with Salmonella choleraesuis followed by infection with PRRS virus was studied. Fifty-four five-week-old Salmonella-free pigs were randomized into 8 treatment groups involving all combinations of the following parameters: S. choleraesuis (S) on day 0; PRRS (P) virus on day 3; and dexamethasone (D; 2mg/kg) on days 3 to 7. DEX was used as a proxy for stress. Clinical signs of disease were monitored daily. Body weight was determined on day 0 and at necropsy. Serum, feces, tonsil and nasal swabs were collected on days 0, 3, 7, 10, 14, 17, and 21. All pigs were necropsied on day 21 and tissues were collected for bacteriology. Pigs receiving PSD were more adversely affected than any other group followed by PS and SD. A statistical significance in mortality was observed for the PSD group (p=0.010). Temperature response was a result of infection with Salmonella but was exacerbated with either combination of P or D. More tissues were positive for Salmonella from the PSD group followed by SD, PS and S alone. Additionally, the PSD group shed significantly higher numbers of Salmonella (p<0.05) than any other group. These data indicate that clinical outbreaks of disease may be exacerbated when co-infection with Salmonella and PRRS occurs.