TY - JOUR
T1 - Nonstructural Carbohydrate and Undegradable Protein Sources in the Diet
T2 - Growth Responses of Dairy Heifers
AU - Casper, David P.
AU - Schingoethe, David J.
AU - Brouk, Michael J.
AU - Maiga, Harouna A.
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 1994
Y1 - 1994
N2 - Thirty-five 3-mo-old 150-kg Holstein heifers were fed diets containing two nonstructural carbohydrate sources (corn or barley) with two quantities of undegradable protein (soybean meal or extruded soybean meal) for 9 wk in a 2 × 2 factorial arrangement to evaluate NRC guidelines that the diet contain increased quantities of undegraded intake protein. Total mixed diets fed for ad libitum intake contained approximately 17.4% CP, consisting of 16.7% corn silage (DM basis), 33.3% chopped alfalfa hay, and 50% concentrate mix. Average daily gains were greater for heifers fed extruded soybean meal, but response was greater when heifers were fed barley-extruded soybean meal (1.12, 1.13, 1.05, and 1.23 kg/d for corn-soybean meal, corn-extruded soybean meal, barley-soybean meal, and barley-extruded soybean meal, respectively) than diets of barley-soybean meal. Extruded soybean meal increased DMI (5.9, 6.1, 5.2, and 6.7 kg/d), but DMI were similar when diets based on corn or barley were fed. Diets with greater concentrations of undegraded intake protein fed to dairy heifers resulted in greater DMI and average daily gains, but responses were greater when heifers were fed diets based on barley rather than corn. These results suggest that current NRC recommendations for undegraded intake protein fed to 3- to 6-mo-old dairy heifers are too high; diets containing 35 to 40% undegraded intake protein should be sufficient.
AB - Thirty-five 3-mo-old 150-kg Holstein heifers were fed diets containing two nonstructural carbohydrate sources (corn or barley) with two quantities of undegradable protein (soybean meal or extruded soybean meal) for 9 wk in a 2 × 2 factorial arrangement to evaluate NRC guidelines that the diet contain increased quantities of undegraded intake protein. Total mixed diets fed for ad libitum intake contained approximately 17.4% CP, consisting of 16.7% corn silage (DM basis), 33.3% chopped alfalfa hay, and 50% concentrate mix. Average daily gains were greater for heifers fed extruded soybean meal, but response was greater when heifers were fed barley-extruded soybean meal (1.12, 1.13, 1.05, and 1.23 kg/d for corn-soybean meal, corn-extruded soybean meal, barley-soybean meal, and barley-extruded soybean meal, respectively) than diets of barley-soybean meal. Extruded soybean meal increased DMI (5.9, 6.1, 5.2, and 6.7 kg/d), but DMI were similar when diets based on corn or barley were fed. Diets with greater concentrations of undegraded intake protein fed to dairy heifers resulted in greater DMI and average daily gains, but responses were greater when heifers were fed diets based on barley rather than corn. These results suggest that current NRC recommendations for undegraded intake protein fed to 3- to 6-mo-old dairy heifers are too high; diets containing 35 to 40% undegraded intake protein should be sufficient.
KW - ADG
KW - B
KW - C
KW - DIP
KW - ESBM
KW - NSC
KW - SBM
KW - UIP
KW - average daily gain
KW - barley
KW - corn
KW - extruded SBM
KW - heifers
KW - nonstructural carbohydrates
KW - nonstructural carbohydrates
KW - ruminally degraded intake protein
KW - ruminally undegraded intake protein
KW - soybean meal
KW - undegradable protein
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U2 - 10.3168/jds.S0022-0302(94)77200-3
DO - 10.3168/jds.S0022-0302(94)77200-3
M3 - Article
C2 - 7814729
AN - SCOPUS:0028506659
VL - 77
SP - 2595
EP - 2604
JO - Journal of Dairy Science
JF - Journal of Dairy Science
SN - 0022-0302
IS - 9
ER -