SYSTEM OF EQUATIONS FOR FULFILLING NET ENERGY AND ABSORBED PROTEIN-REQUIREMENTS FOR MILK COMPONENT PRODUCTION

被引:10
作者
MERTENS, DR [1 ]
DADO, RG [1 ]
机构
[1] UNIV WISCONSIN,DEPT DAIRY SCI,MADISON,WI 53706
关键词
ABSORBED PROTEIN; NET ENERGY; MILK COMPONENTS; RATION FORMULATION;
D O I
10.3168/jds.S0022-0302(93)77686-9
中图分类号
S8 [畜牧、 动物医学、狩猎、蚕、蜂];
学科分类号
0905 ;
摘要
Objectives were to develop a system of equations for formulating rations to meet absorbed protein requirements, to define NE(L) requirements for individual milk components, and to evaluate the effects of changes in milk composition on requirements for absorbed protein and NE(L) recommended by NRC or by a proposed system based on milk components. By combining parameters in the NRC degradable protein system, a set of two equations was derived that can be solved to meet absorbed protein requirements when either ruminally available protein or energy limits microbial protein synthesis. Heats of combustion were used to estimate NE(L) requirements for milk components. Maintenance requirements for absorbed protein and NE(L) were obtained from NRC. To eliminate the dependence of DMI prediction on milk fat concentration, as assumed by NRC, DMI was estimated using the NDF concentration of the feed and the NE(L) requirement of the cow. The proposed system of requirements, based on milk components and the matrix of equations for meeting absorbed protein requirements, not only accounts for differences in the degradability and microbial yield of feeds but also more logically matches differences in nutrient requirements for milk components associated with changes in milk composition.
引用
收藏
页码:3464 / 3478
页数:15
相关论文
共 20 条
[1]  
ABDERHALDEN E, 1908, TXB PHYSL CHEM 30 LE
[2]  
[Anonymous], 1989, NUTRIENT REQUIREMENT, V5th
[3]  
[Anonymous], 1985, RUMINANT NITROGEN US
[5]  
BUCKMASTER DR, 1989, DAFOSYM DAIRY FORAGE, P87
[6]  
CHALUPA W, 1991, P CORNELL NUTR C, P45
[7]   METABOLIZABLE ENERGY AND ABSORBED PROTEIN-REQUIREMENTS FOR MILK COMPONENT PRODUCTION [J].
DADO, RG ;
MERTENS, DR ;
SHOOK, GE .
JOURNAL OF DAIRY SCIENCE, 1993, 76 (06) :1575-1588
[8]  
DOMALSKI DS, 1972, J PHYS CHEM REF DATA, V1, P221
[9]  
ERDMAN R, 1991, P MAR NUTR C FEED MA, P49
[10]   COMPOSITION OF FORMALDEHYDE-TREATED AND FORMIC ACID-TREATED ALFALFA AND ORCHARDGRASS SILAGES HARVESTED AT 2 MATURITIES AND THEIR EFFECTS ON INTAKE AND GROWTH BY HOLSTEIN HEIFERS [J].
GOERING, HK ;
WALDO, DR ;
TYRRELL, HF ;
THOMSON, DJ .
JOURNAL OF ANIMAL SCIENCE, 1991, 69 (11) :4634-4643