Staphylococcus aureus Isolates from Bovine Mastitis in Eight Countries: Genotypes, Detection of Genes Encoding Different Toxins and Other Virulence Genes

Staphylococcus aureus (S. aureus) is recognized worldwide as one of the major agent of dairy cow intra-mammary infections. This microorganism can express a wide spectrum of pathogenic factors used to attach, colonize, invade and infect the host. The present study considered 120 isolates from eight different countries that were investigated for 27 different virulence factors to increase the knowledge on the circulating genetic lineages among the cow population with mastitis. Among the virulence factors, fmtB, cna, clfA and leukotoxins genes were the most frequent. The sea and sei genes were present in seven out of eight countries; seh gene showed high frequency in South American countries while sel gene was harboured especially in Mediterranean countries. The etb, seb and see genes were not detected in any of the isolates, while only two isolates were MRSA confirming the low diffusion of methicillin resistance microorganism among bovine mastitis isolates. This work demonstrated the wide variety of S. aureus genotypes found in dairy cattle worldwide. This condition suggests that considering the region of interest might help to formulate strategies for reducing the infection spreading.Fil: Monistero, Valentina. Università degli Studi di Milano; ItaliaFil: Graber, Hans Ulrich. Agroscope. Research Division. Food Microbial Systems; SuizaFil: Pollera, Claudia. Università degli Studi di Milano; ItaliaFil: Cremonesi, Paola. Consiglio Nazionale delle Ricerche; ItaliaFil: Castiglioni, Bianca. Consiglio Nazionale delle Ricerche; ItaliaFil: Bottini, Enriqueta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; ArgentinaFil: Ceballos Marquez, Alejandro. Universidad de Caldas; ColombiaFil: Lasso-Rojas, Laura. Universidad de Caldas; ColombiaFil: Kroemker, Volker. University of Applied Sciences and Arts; AlemaniaFil: Wente, Nicole. University of Applied Sciences and Arts; AlemaniaFil: Petzer, Inge Marie. University of Pretoria. Faculty of Veterinary Science; SudáfricaFil: Santisteban, Carlos. Cornell University; Estados UnidosFil: Runyan, Jeff. Cornell University; Estados UnidosFil: Santos, Marcos Veiga dos. Universidade de Sao Paulo; BrasilFil: Alves, Bruna Gomes. Universidade de Sao Paulo; BrasilFil: Piccinini, Renata. Università degli Studi di Milano; ItaliaFil: Bronzo, Valerio. Università degli Studi di Milano; ItaliaFil: Abbassi, Mohamed Salah. University of Tunis El Manar; TúnezFil: Said, Meriam Ben. University of Tunis El Manar; TúnezFil: Moroni, Paolo. Cornell University; Estados Unidos. Università degli Studi di Milano; Itali