title: Prevalence and antibiotic susceptibility of coagulase-negative Staphylococcus species from bovine subclinical mastitis in dairy herds in the central region of Argentina.
abstract: Coagulase-negative staphylococci (CNS) are a common cause of bovine subclinical mastitis (SCM). The prevalence of CNS species causing SCM identified by genotyping varies among countries. Overall, the antimicrobial resistance in this group of organisms is increasing worldwide; however, little information exists about a CNS species resistant to antibiotics. The aim of the present study was to genotypically characterize CNS at species level and to determine the prevalence and antibiotic resistance profiles of CNS species isolated from bovine SCM in 51 dairy herds located in the central region of the province of Cordoba, Argentina. In this study, we identified 219 CNS isolates at species level by PCR-restriction fragment length polymorphism of the groEL gene. Staphylococcus chromogenes (46.6%) and Staphylococcus haemolyticus (32%) were the most prevalent species. A minimum of three different CNS species were present in 41.2% of the herds. S. chromogenes was isolated from most of the herds (86.3%), whereas S. haemolyticus was isolated from 66.7% of them. The broth microdilution method was used to test in vitro antimicrobial susceptibility. Resistance to a single compound or two related compounds was expressed in 43.8% of the isolates. S. chromogenes and S. haemolyticus showed a very high proportion of isolates resistant to penicillin. Resistance to two or more non-related antimicrobials was found in 30.6% of all CNS. S. haemolyticus exhibited a higher frequency of resistance to two or more non-related antimicrobials than S. chromogenes.
authors.affiliation: Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas,Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta 36 km 601 (X5806JRA), Río Cuarto, Córdoba, Argentina. Electronic address: craspanti@exa.unrc.edu.ar.
authors.forename: Claudia G
authors.initials: CG
authors.lastname: Raspanti
authors.affiliation: Laboratorio de Diagnóstico Veterinario - Calidad de Leche - Nutrición Animal, CP 436 Parajón Ortiz (X5900KBJ), Villa María, Córdoba, Argentina.
authors.forename: Cesar C
authors.initials: CC
authors.lastname: Bonetto
authors.affiliation: Departamento de Patología Animal, Facultad de Agronomía y Medicina Veterinaria, Universidad Nacional de Río Cuarto, Ruta 36 km 601 (X5806JRA), Río Cuarto, Córdoba, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina.
authors.forename: Claudina
authors.initials: C
authors.lastname: Vissio
authors.affiliation: Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas,Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta 36 km 601 (X5806JRA), Río Cuarto, Córdoba, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina.
authors.forename: Matías S
authors.initials: MS
authors.lastname: Pellegrino
authors.affiliation: Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas,Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta 36 km 601 (X5806JRA), Río Cuarto, Córdoba, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina.
authors.forename: Elina B
authors.initials: EB
authors.lastname: Reinoso
authors.affiliation: Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas,Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta 36 km 601 (X5806JRA), Río Cuarto, Córdoba, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina.
authors.forename: Silvana A
authors.initials: SA
authors.lastname: Dieser
authors.affiliation: Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas,Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta 36 km 601 (X5806JRA), Río Cuarto, Córdoba, Argentina.
authors.forename: Cristina I
authors.initials: CI
authors.lastname: Bogni
authors.affiliation: Departamento de Patología Animal, Facultad de Agronomía y Medicina Veterinaria, Universidad Nacional de Río Cuarto, Ruta 36 km 601 (X5806JRA), Río Cuarto, Córdoba, Argentina.
authors.forename: Alejandro J
authors.initials: AJ
authors.lastname: Larriestra
authors.affiliation: Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas,Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta 36 km 601 (X5806JRA), Río Cuarto, Córdoba, Argentina.
authors.forename: Liliana M
authors.initials: LM
authors.lastname: Odierno
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001118:Argentina; D002417:Cattle; D003030:Coagulase; D003612:Dairying; D005260:Female; D008414:Mastitis, Bovine / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D013210:Staphylococcus / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D003030:Coagulase
keywords: Antimicrobial resistance; Bovines; Bovinos; Coagulase-negative staphylococci species; Especies de estafilococos coagulasa negativos; Mastitis subclínica; Resistencia a antimicrobianos; Subclinical mastitis