title: Prevalence and distribution of Listeria monocytogenes serotypes and pulsotypes in sows and fattening pigs in farrow-to-finish farms (France, 2008).
abstract: This study was undertaken to acquire new data on the prevalence of Listeria monocytogenes in sows and fattening pigs in farrow-to-finish pig farms, and to analyze distribution of serotypes and genotypes of the bacterium within farms. Detection of L. monocytogenes was carried  out on 730 pooled feces samples from sows in 73 pig farms and on 172 pooled feces samples from fattening pigs in 43 of these farms. Isolates were serotyped and typed by pulsed-field gel electrophoresis. For sows, 46% of the farms and 11% of the samples were positive for L. monocytogenes.  A total of 124 isolates were collected and distributed in four serotypes: 1/2a (41%), 1/2b (36%), 4b (21%), and 1/2c (2%). Positive farms harbored one to three serotypes. The genetic diversity was high; 51 genetic profiles were obtained with 25, 16, 9, and 1 for the serotypes 1/2a, 1/2b, 4b,  and 1/2c, respectively. Positive farms harbored 1 to 6 genetic profiles. Isolates showing similar genotypes occurred in several farms. For fattening pigs, 25% of the farms and 14.5% of the samples were positive for L. monocytogenes. The 34 isolates belonged to four serotypes: 1/2a (32%),  1/2b (41%), 4b (24%), and 1/2c (3%). They were distributed in 20 genotypes: 6 for 1/2a; 8 for 1/2b, 5 for 4b, and 1 for 1/2c. Similar serotypes and pulsotypes were recovered in sows and fattening pigs from the same farms, suggesting common sources of contamination.
authors.affiliation: Anses, Unité Hygiéne et Qualité des Produits Avicoles et Porcins, BP53, 22440 Ploufragan, France. evelyne.boscher@anses.fr
authors.forename: Evelyne
authors.initials: E
authors.lastname: Boscher
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Houard
authors.forename: Martine
authors.initials: M
authors.lastname: Denis
mesh_terms: D000818:Animals; D003257:Consumer Product Safety; D016521:Electrophoresis, Gel, Pulsed-Field; D005243:Feces / Q000382:microbiology; D005506:Food Contamination / Q000032:analysis / Q000517:prevention & control; D005516:Food Microbiology; D005602:France / Q000453:epidemiology; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008089:Listeria monocytogenes / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D008088:Listeriosis / Q000453:epidemiology / Q000382:microbiology; D015995:Prevalence; D012703:Serotyping; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology / Q000382:microbiology