Survival of Streptococcus uberis on bedding substrates

Abstract

Streptococcus uberis (S. uberis) is a mastitis pathogen with an environmental reservoir. Management factors related to housing design and bedding are associated with the risk of S. uberis mastitis. This study aimed to investigate the ability of five distinct strains of S. uberis to survive and replicate on three common bedding materials (sand, wheat straw and kiln dried pine sawdust). Sterilized bedding substrates were inoculated with S. uberis and incubated at room temperature. Bacterial recovery from these media over time indicated that S. uberis numbers increased on used bedding materials, suggesting the addition of faeces and urine promoted replication. The bacterium was recovered for at least 35 days on straw and sand bedding, but could not be recovered beyond 7 days on clean or used sawdust. This study demonstrates the importance of bedding type and management on the environmental survival of S. uberis.

Keywords: Dairy cattle; Mastitis; Microbiology; Streptococcus uberis.