Submitted to: Pig Veterinary Society International Congress Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 6/5/2002
Publication Date: 6/5/2002
Citation: HURD, H.S., MCKEAN, J., GRIFFITH, R., ROSTAGNO, M.H. MEASURING SALMONELLA PREVALENCE IN FINISH SWINE: EVALUATION OF THREE METHODS. PROCEEDINGS CONGRESS OF THE INTERNATIONAL PIG VETERINARY SOCIETY. 2002. P. 313. Interpretive Summary:
Technical Abstract: The study objective was to evaluate three methods of Salmonella enterica prevalence estimation in swine herds (fecal culture, culture of abattoir collected samples, and serum ELISA). From each of six swine herds, we necropsied ~ 100 finishing pigs (> 70 Kg); one-half on-farm and the other half at the abattoir, after transport and ~ 2.5 hours holding. We collected the same samples for S. enterica culture at both locations (1 g fecal, 10 g cecal contents, ileocecal lymph nodes, superficial inguinal lymph nodes, 25 g of gluteal muscle for serum ELISA). On-farm, the 1 g fecal sample only detected 13.3% (2 of 15) of all positive pigs necropsied on-farm. However, with abattoir and on-farm results combined, the fecal sample detected 57.4% (74/129) of positive pigs. Abattoir collected samples provided prevalence estimates much higher than on-farm collected samples (39.9% versus 5.3%; P < 0.001). This study shows that fecal samples have a low sensitivity for detecting infected pigs and that abattoir collected samples overestimate the on-farm S. enterica prevalence. For most herds, serology overestimated the on-farm culture prevalence.