Blood Ammonia and Blood Lactic Acid Levels in Dairy Cows after Feeding of Surplus Crude Protein or Starch

Abstract

Twenty-six Holstein cows were divided into five feeding groups given the adequate, the surplus starch, the surplus rumen undegradable intake protein, the surplus rumen degradable intake protein or the surplus rumen soluble intake protein feed, and they were examined for the blood concentrations of ammonia and lactic acid afrer feeding. Blood samples were collected from the jugular vein before and 2 or 4hr after feeding. The blood concentration of ammonia changed in relation to feeding of starch and rumen degradable intake protein, while the concentration of lactic acid as corelated with feeding of starch, indicating that the rumen condition might be estimated from the concentrations of blood ammonia and lactic acid.