Background Drivers of change in dairy herd health management include the significant increase in herd/farm size, quota removal (within Europe) and the increase in technologies to aid in dairy cow reproductive management. Main body There are a number of key areas for improving fertility management these include: i) handling of substantial volumes of data, ii) genetic selection (including impro...

Introduction Proper nutritional status is critical for optimal production efficiency in the beef cow herd. Meeting the nutrient requirements of the productive cow is a prime factor in the cow’s reproductive success and overall herd profitability. However, beef producers often take a “one size fits all” approach to feeding the cows in the cow herd. This singular approach to nutrient supply for t...

The objectives of this study were to describe the relationships between milk urea concentrations and nutritional management, production, and economic variables in commercial dairy herds. Dairy Herd Improvement (DHI) test-day milk urea data, production data, and information on ration nutrient composition and feeding management programs were collected over a 13-mo period from 53 commercial Ontari...

the objective of this study was to determine the optimum replacement strategy using dynamic programming for dairy herds in fars province. a dairy cow is kept several lactations for milk production in the herd. after spending several lactations, milk production gradually begins to decline, while animal health problems rises simultaneously. so one of the most important management decisions of dai...

OBJECTIVE To estimate the prevalence of Mycobacterium avium subsp paratuberculosis infection among cows on beef operations in the United States. DESIGN Cross-sectional seroprevalence study. Sample Population-A convenience sample of 380 herds in 21 states. PROCEDURES Serum samples were obtained from 10,371 cows and tested for antibodies to M avium subsp paratuberculosis with a commercial ELI...

The objective of the study was to screen a large number of herd management practices and herd characteristics from US dairies to identify herd-level risk factors associated with the presence of Listeria monocytogenes in bulk tank milk (BTM). A total of 71 variables was univariately evaluated for their association with the presence of L. monocytogenes in BTM. Results from the univariate analysis...

Many applications of mixed linear statistical models for genetic evaluation of dairy cattle assume that genetic and residual components of variance are each constant across environments. However, this assumption is violated for production and conformation traits, which can reduce accuracy of selection and cause biases in the proportions of breeding animals chosen from each environment. Best lin...