Fresh cow metabolic diseases

Old myths and new data

Abstract

Hypocalcemia, hypophosphatemia, hypomagnesemia, hyperketonemia (ketosis), and hypokalemia are important metabolic diseases of fresh dairy cows. Many dairy practitioners and dairy producers need to update their approaches to these diseases because of new findings about these disorders. Hypocalcemia in standing cows is best treated orally; intravenous calcium causes a rebound hypocalcemia and should be reserved for recumbent cases of milk fever. Glucose or additional electrolytes should not be administered intravenously to cows with hypocalcemia. The strategic use of oral calcium helps manage subclinical hypocalcemia. Hypophosphatemia is less common and is usually secondary to hypocalcemia. Mild to moderate cases of hypophosphatemia are best treated with oral phosphorus; intravenous phosphorus is best reserved for severe cases. Hypomagnesemia may be a clinical problem in grazing herds or a subclinical problem in cows fed stored feeds. Clinical cases may be treated intravenously or via rectal enema; subclinical cases are best managed by oral magnesium supplementation. Ketosis (hyperketonemia) is a very common problem in early lactation cows. Early detection and early treatment of hyperketonemia is key. Hypokalemia may follow prolonged periods of anorexia in early lactation cows. Oral potassium supplementation is the best means of treating and preventing hypokalemia.