Case Study

Pregnancy Toxemia in a Sheep Flock

Abstract

A large sheep flock was experiencing a high prevalence of metabolic diseases early in the lambing season. Pregnancy toxemia and secondary hypocalcemia were diagnosed based on history, physical examination and serum biochemistry results. A new approach to metabolic profiling, using pooled sera samples to reduce costs, was used to assess nutritional status of the flock. Ewes close to the time of lambing were found to be in severe negative energy balance, resulting in excessive fat mobilization and clinical signs associated with pregnancy toxemia and hepatic lipidosis. Inadequate amount of fermentable carbohydrates, which could provide glucose to support late pregnancy requirements, was determined by nutrient analysis. Lower cost by-product feeds had been substituted into the new pellet formulation. Although feed costs are a substantial component of production costs, feed changes based solely on cost may not be appropriate relative to nutritional needs and animal health.