Submitted to: Research Workers in Animal Diseases Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 11/12/2002
Publication Date: 11/12/2002
Citation: WESLEY, I.V., PINKERTON, A.L., RIVERA, F., LARSEN, S.T., HURD, H.S., MCKEAN, J., GRIFFITH, R., FRANA, T., NANNAPANENI, R., WAGNER, D. THE PREVALENCE OF L. MONOCYTOGENES IN CULL SOWS. CONFERENCE OF RESEARCH WORKERS IN ANIMAL DISEASES. 2002. ABSTRACT P. 69.
Technical Abstract: The goal of this study was to determine if the cull sow, when compared to the younger market-weight hog, presents any additional risk of introducing L. monocytogenes (LM) into the food chain. Two trials were conducted at a single cull sow packing plant in 2001 (n = 179 sows) and in 2002 (n = 160 sows). Animal tissues, carcass and environmental swabs were analyzed. LM was detected in 0.14% of the total samples (n = 2,858); Listeria spp., in 5.98% of samples. In Trial I, LM was detected in gut contents (2 hogs) and on both carcass swabs of another hog. Isolates were of either serotype 1a (gut isolates) or 4b (carcass swabs), which is the serotype associated with human foodborne outbreaks. Isolates were highly virulent (> 90%) in the cell hybridoma assay and similar in antimicrobial resistance profiles. In Trial II, LM was found in a single, chopped pork sample. In a previous study of 300 young market-weight hogs, we recovered LM from 2.5% of hog tissues (n = 1,849) and in ~ 50% of ground pork (n=340) samples. Thus, the prevalence of LM in the cull sow is at least comparable to that of market-weight hogs.