Somatic cell count control strategies in dairy ewes

The consumption of milk products, especially made from raw milk, have been reported to be associated with food borne diseases. Since most sheep’s milk products are made from raw milk, it is clear how udder health is an important prerequisite to produce hygienic milk. Ewes with mastitis, particularly in their subclinical form, serve as reservoir of pathogens that can be shed into the milk and constitute a potential risk for human health. Milk somatic cell count (SCC) is not a public health concern itself but it is an indicator of the general state of udder health in a dairy sheep flock and can be used as an indication of hygienic milk and to improve safety of dairy products. This thesis presents three different strategies, within a comprehensive SCC control program in dairy ewes. All the studies were carried out at the University of Wisconsin, Madison dairy sheep research facility, which is the only University dairy sheep research station in North America. The study presented in Chapter 2 describes an automated method to assess SCC on farm. In Chapter 3 is presented a study aimed to determine the effect of intramammary antibiotic dry treatment on intramammary infection and somatic cell count in the subsequent lactation. Chapter 4 presents a study carried out to assess the impact of premilking teat sanitation on somatic cell count in dairy ewes. In Chapter 5 are presented the results of the combined effect of dry treatment and teat sanitation on SCC in dairy ewes.