Juniper Publishers Journal of Dairy and Veterinary Sciences

Journal of Dairy & Veterinary Sciences - Juniper Publishers   Introduction Ketosis is a major metabolic disorder of dairy cattle in the United States, affecting an estimated 40% of all lactations in the industry, between clinical and subclinical cases [ 1 ]. Clinical ketosis is characterized by high levels of ketones in the blood and is manifested by lethargy and anorexia in the peri-partum dairy cow [ 2 ]. Subclinical ketosis (SCK) requires a blood, milk, or urine test to diagnose. Even though it is not outwardly noticeable, it is still estimated to cost the farmer $289/case due to both the direct and indirect costs, especially with the loss in milk yield [ 3 ]. It has been shown that ketosis and negative energy balance have negative consequences on reproduction and immune function [ 4 ]. Subclinical ketosis is often defined as blood BHB concentrations of >1.2mM/L and < 3.0 mM/L [ 1 ]. McArt et al. [ 5 ] showed that PPG h...

Journal of Dairy & Veterinary Sciences - Juniper Publishers   Introduction The spread of mastitis pathogens causes large economic losses to the dairy industry. These losses include increased involuntary culling rate, reduced milk production, increase domatic cell count, and discarded milk [ 1 , 2 ]. Costs associated with mastitis infections in the U.S. dairy industry have been estimated at nearly US $2 billion per year [ 3 ]. Streptococcus uberis is one of the most common gram-positive causes of clinical mastitis and contributes to a large proportion of subclinical mastitis cases [ 4 , 5 ]. Streptococcus uberis infections are often difficult to cure with traditional intra-mammary antibiotic preparations, especially in older animals [ 6 , 7 ]. Similar to treatment trials focused on Staphylococcus aureus ( S. aureus ) intra-mammary infection, increased somatic cell counts before treatment was associated with a decreased probability o...