Genomic insights into methicillin-resistant staphylococci and mammaliicocci from bulk tank milk of dairy farms in Serbia

Kos, Andrea (author), Papić, Bojan (author), Golob, Majda (author), Avberšek, Jana (author), Kušar, Darja (author), Ledina, Tijana (author), Đorđević, Jasna (author), Bulajić, Snežana (author)

The potential risk to human and animal health provides a rationale for research on methicillin-resistant staphylococci (MRS) and mammaliicocci (MRM) in dairy herds. Here, we aimed to estimate their occurrence in the bulk tank milk (BTM) samples collected in 2019–2021 from 283 bovine dairy farms in the Belgrade district. We used whole-genome sequencing to characterize the obtained isolates and assess their genetic relatedness. A total of 70 MRS/MRM were recovered, most frequently Staphylococcus haemolyticus and Mammaliicoccus sciuri. Five clusters of 2–4 genetically related isolates were identified and epidemiological data indicated transmission through, e.g., farm visits by personnel or milk collection trucks. Most MRSA isolates belonged to the typical livestock-associated lineage ST398-t034. One MRSA isolate (ST152-t355) harbored the PVL-encoding genes. Since MRS/MRM isolates obtained in this study frequently harbored genes conferring multidrug resistance (MDR), this argues for their role as reservoirs for the spread of antimicrobial resistance genes. The pipeline milking system and total bacterial count >100,000 CFU/mL were significantly associated with higher occurrences of MRS/MRM. Our study confirms that BTM can be a zoonotic source of MRS, including MDR strains. This highlights the urgent need for good agricultural practices and the continuous monitoring of MRS/MRM in dairy farms.

• Language: English
• Keywords: Staphylococcus aureus, milk, virulence factors, whole genome sequencing
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: VF - Veterinary Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2023
• Number of pages: 19 str.
• Numbering: Vol. 10, issue 10, [art. no.] 1529
• PID: 20.500.12556/RUL-151615
• UDC: 636.09:616:577
• ISSN on article: 2079-6382
• DOI: 10.3390/antibiotics12101529
• COBISS.SI-ID: 167972099
• Publication date in RUL: 12.10.2023

Record is a part of a journal

• Title: Antibiotics
• Shortened title: Antibiotics
• Publisher: MDPI
• ISSN: 2079-6382
• COBISS.SI-ID: 522975769

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 12.10.2023

Projects

• Funder: Other - Other funder or multiple funders
• Project number: BI-RS/23-25-007
• Name: Surovo mleko kot potencialni vir večkratno odpornih bakterij in genov za odpornost

• Funder: ARRS - Slovenian Research Agency
• Project number: P4-0092
• Name: Zdravje živali, okolje in varna hrana