ABOMASAL PROTEIN AND AMINO ACIDS IN STEERS FED DIFFERENT PROTEIN SUPPLEMENTS

Abstract

The quantities of nitrogen, protein, essential and nonessential amino acids reaching the abomasum of steers fed three different sources of supplemental nitrogen were estimated. When corn gluten meal (CGM) was the nitrogen supplement, more total nitrogen, protein, essential and nonessential amino acids reached the abomasum daily than were observed with distiller’s dried solubles (DDS) or soybean meal (SBM) supplements. Corn gluten meal resulted in significantly more total grams of abomasal isoleucine, leucine, methionine and phenylalanine reaching the abomasum. No differences were observed between DDS or SBM in total nitrogen, protein or essential amino acids reaching the abomasum. The molar percentage of plasma lysine was higher and threonine lower when CGM was fed than the values obtained when either DDS or SBM were fed. Lower plasma leucine and phenylalanine were observed when the DDS-supplemented ration was fed.