Confirmed bacteriological diagnosis and cure of nonsevere gram-positive clinical mastitis cases enrolled in a randomized clinical trial based on results of on-farm culture.

Our objectives were to describe the confirmed bacteriological diagnosis of mastitis pathogens cultured from cases of nonsevere clinical mastitis (CM) identified as gram-positive (GP) using on-farm culture and to compare differences in bacteriological cure (BC) based on antimicrobial (AM) therapy. Cows that developed nonsevere CM in a single quarter were enrolled in a randomized clinical trial based on microbial growth on GP selective agars. Cows were randomly assigned to receive a once-daily intramammary treatment: 3 d hetacillin (n = 69), 3 d ceftiofur (n = 69), 8 d ceftiofur (n = 70), or to a nontreated group (n = 32).

Relationship between facility type and bulk tank milk bacteriology, udder health, udder hygiene, and milk production on Vermont organic dairy farms.

The primary objective of this cross-sectional observational study was to determine whether bulk tank milk quality, udder health, udder hygiene, and milk production outcomes were associated with facility type on organic dairies. A secondary objective was to identify other management-related risk factors associated with bulk tank milk quality, udder health, udder hygiene, and milk production on organic dairy herds in Vermont. We aimed to enroll 40 farms, to compare herds using the 2 most common systems (freestalls, tiestalls) for housing organic dairy cattle in the state with those using a bedded pack during the nongrazing season (typically November-May).

The impact of kit, environment, and sampling contamination on the observed microbiome of bovine milk.

In low-microbial biomass samples such as bovine milk, contaminants can outnumber endogenous bacteria. Because of this, milk microbiome research suffers from a critical knowledge gap, namely, does non-mastitis bovine milk contain a native microbiome? In this study, we sampled external and internal mammary epithelia and stripped and cisternal milk and used numerous negative controls, including air and sampling controls and extraction and library preparation blanks, to identify the potential sources of contamination. Two algorithms were used to mathematically remove contaminants and track the potential movement of microbes among samples.

Exploring associations between the teat apex metagenome and intramammary infections in primiparous cows under organic directives.

Unlabelled: The primary objective of this study was to identify associations between the prepartum teat apex microbiome and the presence of intramammary infections (IMI) in primiparous cows during the first 5 weeks after calving. We performed a case-control study using shotgun metagenomics of the teat apex and culture-based milk data collected longitudinally from 710 primiparous cows on five organic dairy farms. Cases had higher odds of having metagenomic DNA on the teat apex prior to parturition compared to controls (OR = 38.