title: Listeria monocytogenes in faeces from clinically healthy dairy cows in Sweden.
abstract: Faecal samples from 102 clinically healthy dairy cows, representing 34 farms in the Swedish province of Uppsala, were analysed for the presence of Listeria spp. using an enrichment procedure. Listeria monocytogenes was isolated from six (6%) and L. innocua from 2 (2%) cows. From each of the 6 samples positive for L. monocytogenes, 5 isolates were further characterised by restriction enzyme analysis using the 3 enzymes Apa I, Sma I, and Asc I, followed by pulsed-field gel electrophoresis. Three of the L. monocytogenes positive cows lived at the same farm, and they all harboured the same clonal type. One of these 3 cows also harboured a further clonal type of L. monocytogenes. The fact that one of the cows harboured 2 different clonal types of L. monocytogenes is important from an epidemiological point of view when routes of infection are to be investigated.
authors.affiliation: Department of Food Hygiene, Faculty of Veterinary Medicine, Swedish University of Agricultural Sciences, Uppsala, Sweden. helle.unnerstad@lmhyg.slu.se
authors.forename: H
authors.initials: H
authors.lastname: Unnerstad
authors.forename: A
authors.initials: A
authors.lastname: Romell
authors.forename: H
authors.initials: H
authors.lastname: Ericsson
authors.forename: M L
authors.initials: ML
authors.lastname: Danielsson-Tham
authors.forename: W
authors.initials: W
authors.lastname: Tham
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology / Q000382:microbiology*; D004269:DNA, Bacterial / Q000737:chemistry / Q000302:isolation & purification; D015252:Deoxyribonucleases, Type II Site-Specific / Q000737:chemistry; D004197:Disease Reservoirs / Q000662:veterinary*; D016521:Electrophoresis, Gel, Pulsed-Field / Q000662:veterinary; D005243:Feces / Q000382:microbiology*; D005260:Female; D008089:Listeria monocytogenes / Q000737:chemistry / Q000145:classification* / Q000235:genetics; D008088:Listeriosis / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D015183:Restriction Mapping / Q000662:veterinary; D013548:Sweden / Q000453:epidemiology
chemical_list: D004269:DNA, Bacterial; C078382:endodeoxyribonuclease AscI; C025651:CCCGGG-specific type II deoxyribonucleases; D015252:Deoxyribonucleases, Type II Site-Specific; C038485:GGGCCC-specific type II deoxyribonucleases