Molecular typing of mastitis-causing Staphylococcus aureus isolated from heifers and cows

• Grant number: 13/04123-0
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: April 01, 2013
• End date: September 30, 2013
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Preventive Veterinary Medicine
• Principal Investigator: Juliana Rodrigues Pozzi Arcaro
• Grantee: Juliana Rodrigues Pozzi Arcaro
• Host Institution: Instituto de Zootecnia. Agência Paulista de Tecnologia dos Agronegócios (APTA). Nova Odessa , SP, Brazil
• City of the host institution: Nova Odessa

Abstract

Staphylococcus aureus is among the main etiologic agents of bovine mastitis. A total of 83 isolates of S. aureus from mammary glands of primiparous heifers were collected in the prepartum, calving and during lactation. For lactating cows, a total of 27 isolates of S. aureus from mammary glands were collected during lactation. The samples were taken in two dairy farms located in São Paulo State, Brazil. The highest frequency of S. aureus isolation in heifers was at the end of lactation. Strains were typified through PFGE and grouped according to patterns of restriction enzyme SmaI. PFGE generated seven clonal profiles that were grouped into three different lineages, with the LA lineage being predominant and identified in heifers, as well as in the cows from the two regions studied. It was concluded that the cows showed a significant source of dispersion of S. aureus. At the first lactation the heifers were infected by the same clonal profiles of S. aureus which were isolated from multiparous lactating cows. The heifers were infected during milking over the months of lactation. (AU)