Is staphylococci population from milk of healthy goats safe?
The aim of this study was to assess the species and the genetic diversity of the staphylococci population in raw milk from healthy goats. Isolates representative of all genotypes were screened for their potential pathogenicity by the occurrence of some relevant safety-related properties, such as antibiotic resistance, presence of virulence factor genes, biofilm formation ability and biogenic amine production. A total of 314 staphylococci were isolated, and randomly amplified polymorphic DNA-PCR analysis displayed 48 genotypes. Isolates were identified as belonging to S. epidermidis (87.5%), S. caprae (6.2%), S. aureus (4.2%) and S. simulans (2.1%) species. The antibiotic resistance varied strongly with strains, with S. epidermidis and S. aureus strains showing resistance to more number of antibiotics. A high occurrence of strains harbouring hemolysin genes was also found in both species. On the contrary, none of the strains assayed harboured enterotoxin or amino acid decarboxylase genes, and, although a moderate or high biofilm formation was observed in 29% of the strains, they did not harbour icaA or icaD genes. This study gives a first and extensive picture of safety-related properties within Staphylococcus species isolated from milk of healthy goats, displaying that these species can act as a reservoir for spreading genes related to safety.
Department of Analytical Chemistry and Food Technology, Environmental Sciences and Biochemistry Faculty, University of Castilla-La Mancha, Avda. Carlos III, s/n, 45071 Toledo, Spain.
Patricia
P
Ruiz
Department of Analytical Chemistry and Food Technology, Environmental Sciences and Biochemistry Faculty, University of Castilla-La Mancha, Avda. Carlos III, s/n, 45071 Toledo, Spain.
Iris
I
Barragán
Department of Analytical Chemistry and Food Technology, Environmental Sciences and Biochemistry Faculty, University of Castilla-La Mancha, Avda. Carlos III, s/n, 45071 Toledo, Spain.
Susana
S
Seseña
Department of Analytical Chemistry and Food Technology, Environmental Sciences and Biochemistry Faculty, University of Castilla-La Mancha, Avda. Carlos III, s/n, 45071 Toledo, Spain. Electronic address: MariaLlanos.Palop@uclm.es.
María Llanos
ML
Palop
D000588:Amines / Q000737:chemistry; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D018441:Biofilms; D024881:Drug Resistance, Bacterial; D004352:Drug Resistance, Microbial / Q000235:genetics; D004768:Enterotoxins / Q000235:genetics; D005516:Food Microbiology; D005838:Genotype; D006041:Goats; D008892:Milk / Q000382:microbiology*; D010641:Phenotype; D013203:Staphylococcal Infections / Q000662:veterinary; D013210:Staphylococcus / Q000235:genetics; D013211:Staphylococcus aureus / Q000235:genetics*; D013212:Staphylococcus epidermidis / Q000235:genetics*; D037521:Virulence Factors / Q000235:genetics
D000588:Amines; D000900:Anti-Bacterial Agents; D004768:Enterotoxins; D037521:Virulence Factors
Antibiotic resistance; Biofilm formation; Goat milk; Safety; Staphylococci; Virulence