Veterinary Ruminant Medicine-Pregnancy Toxemia

Pregnancy Toxemia in CowsPregnancy toxemia or ketosis in cows is a metabolic disease occurring in late gestation, typically occurring when nutrition is inadequate. The disease occurs when maternal glucose homeostasis is disrupted and energy demands cannot meet those of the developing fetus. Pregnancy toxemia is more common in beef cattle than in dairy cattle, primarily because of differences in dietary management and typical timing of late gestation. Individual cows of any breed can be affected by pregnancy toxemia; however, herd problems are most common in beef cattle, which frequently are managed so that late pregnancy coincides with the poorest availability of feed due to the season.ETIOLOGY & PATHOGENESISPregnancy toxemia is precipitated by large or multiple fetuses, feed low in energy or protein or high in poorly digestible fiber, and health conditions that increase energy demand or decrease ability to take in nourishment (eg, lameness, oral diseases). Proposed contributors to clinical disease include glucose deficiency with intermittent hypoglycemia, ketone body accumulation with metabolic acidosis or appetite suppression, and death of the fetus with secondary infection and toxemia.The gravid uterus and fetoplacental unit are major consumers of maternal