A Conceptual Analysis

Johne’s disease (JD) is a chronic, production-limiting disease of ruminants. Control programs aiming to minimize the effects of the disease on the dairy industry have been launched in many countries, including Canada. Those programs commonly focus on strict hygiene and management improvement, often combined with various testing methods. Concurrently, organic dairy farming has been increasing in popularity. Because organic farming promotes traditional management practices, it has been proposed that organic dairy production regulations might interfere with implementation of JD control strategies. However, it is currently unclear how organic farming would change the risk for JD control. This review presents a brief introduction to organic dairy farming in Canada, JD, and the Canadian JD control programs. Subsequently, organic practices are described and hypotheses of their effects on JD transmission are developed. Empirical research is needed, not only to provide scientific evidence for organic producers, but also for smaller conventional farms employing organic-like management practices

Monitoring and Controlling Mastitis on Ontario Dairy Farms

The frequency of use and the marginal costs and marginal value products of mastitis control practices on somatic cell count (SCC) and milk yield are investigated. A survey of current management practices is combined with Dairy Herd Improvement production information to determine the relationships between milk yield, SCC, management practices, and production and producer characteristics under field conditions. The relationships are modeled and compared at the cow and herd level. A moment-generating approach is used in the herd model to determine which, if any, practices are risk reducing. The SCC for an individual cow is a better indicator of milk production lost due to mastitis than is a bulk tank SCC. Most recommended mastitis control practices are estimated to be economically beneficial, but some common practices are found not to be economical, and questions are raised about dry cow treatment