Investigation of the relationship between bedding materials, bedding characteristics, and intramammary infection in late lactation dairy cows

Interim findings

Abstract

Many cows acquire subclinical intramammary infections (IMI) during lactation, necessitating antimicrobial treatment at dry-off (dry cow therapy). If the dairy industry moves toward the adoption of selective dry cow therapy, one essential strategy to reduce mastitis-associated antimicrobial use at dry off will be to reduce the incidence of new IMI during lactation. One important source of mastitis-causing pathogens is bedding. However studies are needed to investigate the association between bedding management, bedding bacteria count (BBC), and IMI risk in late lactation cows.

The objectives of this prospective cross-sectional study are to: 1) describe associations between BBC and IMI prevalence for individual pathogens and specific pathogen groups in late lactation cows, 2) identify bedding-related risk factors for high BBC, and 3) identify critical levels of bacteria in bedding that might be used as cut-points to guide practitioners when interpreting BBC reports. This study is ongoing, with winter 2018 results currently being assembled.