Livestock clientele are increasingly expecting increased diagnostic capability from veterinarians. The first ancillary diagnostic testing that generally follows the physical examination are the complete blood count (CBC) and serum biochemistry. This testing can help further define and refine findings from the physical examination and begin to direct specific or supportive therapy or indicate the need for additional diagnostic testing. The goal for this session is for the attendee to interpret the the results of the CBC and chemistry of ruminants. We will focus on areas in which interpretation for ruminants differs from that of other species, including variation in neutrophil activity and ratios, blood urea nitrogen metabolism, creatinine, chloride, and magnesium. Case examples will be provided to facilitate interpretation and application. Treatment options for replacing and managing electrolyte and macro mineral abnormalities will be included.