T Gelbícová1, R Karpísková. 1. Masarykova univerzita, Ustav experimentální biologie, Ceská sbírka mikroorganismů, Brno. terezag@sci.muni.cz
Abstract
BACKGROUND: Evaluation of the incidence and characteristics of L. monocytogenes in samples of raw cow's milk collected on farms (bulk tank milk samples) and from vending machines. MATERIAL AND METHODS: Detection of L. monocytogenes and enumeration were carried out according to EN/ISO 11290--1, 2. Strains were characterised by serotyping and macrorestriction analysis using pulsed-field gel electrophoresis. RESULTS: The presence of L. monocytogenes was detected in 3,2 % (11/346) of bulk tank milk samples and 1,8 % (4/219) samples of raw cow's milk from vending machines. Findings of L. monocytogenes in raw milk were sporadic. Only on one farm strains of L. monocytogenes were detected repeatedly. Thirteen strains of L. monocytogenes belonged to serotype 1/2a, two strains to serotype 1/2b and one to serotype 4b. Macrorestriction analysis revealed considerable heterogeinity of profiles, with nine different pulsotypes being detected. Pulsotype 711 was the most frequent. This pulsotype was found on three different farms. CONCLUSIONS: The incidence of L. monocytogenes in raw cow's milk is relatively low in the Czech Republic. The results confirmed that some clones of L. monocytogenes from raw milk are identical with food and human strains.
BACKGROUND: Evaluation of the incidence and characteristics of L. monocytogenes in samples of raw cow's milk collected on farms (bulk tank milk samples) and from vending machines. MATERIAL AND METHODS: Detection of L. monocytogenes and enumeration were carried out according to EN/ISO 11290--1, 2. Strains were characterised by serotyping and macrorestriction analysis using pulsed-field gel electrophoresis. RESULTS: The presence of L. monocytogenes was detected in 3,2 % (11/346) of bulk tank milk samples and 1,8 % (4/219) samples of raw cow's milk from vending machines. Findings of L. monocytogenes in raw milk were sporadic. Only on one farm strains of L. monocytogenes were detected repeatedly. Thirteen strains of L. monocytogenes belonged to serotype 1/2a, two strains to serotype 1/2b and one to serotype 4b. Macrorestriction analysis revealed considerable heterogeinity of profiles, with nine different pulsotypes being detected. Pulsotype 711 was the most frequent. This pulsotype was found on three different farms. CONCLUSIONS: The incidence of L. monocytogenes in raw cow's milk is relatively low in the Czech Republic. The results confirmed that some clones of L. monocytogenes from raw milk are identical with food and human strains.
Authors: Krzysztof Skowron; Ewa Wałecka-Zacharksa; Katarzyna Grudlewska; Natalia Wiktorczyk; Agnieszka Kaczmarek; Grzegorz Gryń; Joanna Kwiecińska-Piróg; Klaudia Juszczuk; Zbigniew Paluszak; Katarzyna Kosek-Paszkowska; Eugenia Gospodarek-Komkowska Journal: Pol J Microbiol Date: 2019-09-03