Performance and nutrient intake of high producing Holstein cows consuming pasture or a total mixed ration

• Published in: Journal of dairy science 1998-05, Vol.81 (5), p.1403-1411
• Main Authors: Kolver, E.S. (Dairy Research Corporation Ltd., Hamilton, New Zealand.), Muller, L.D
• Format: Article
• Language: English
• Subjects: 3-HYDROXYBUTYRIC ACID; ACIDE GRAS; ACIDOS GRASOS; AFFOURAGEMENT EN VERT; ALIMENT COMPLET POUR ANIMAUX; Animal Feed; Animal Nutritional Physiological Phenomena; Animal productions; Animals; Biological and medical sciences; Blood Glucose - metabolism; BLOOD LIPIDS; Body Composition; BODY CONDITION; BODY WEIGHT; Cattle - physiology; COMPLETE FEEDS; CONDICION CORPORAL; CONTENIDO DE LIPIDOS; CONTENIDO DE MATERIA SECA; CONTENIDO PROTEICO; CONTEO DE CELULAS SOMATICAS; DAIRY COWS; Dietary Fiber - administration & dosage; Dietary Proteins - administration & dosage; DIGESTIBILIDAD; DIGESTIBILITE; DIGESTIBILITY; DRY MATTER CONTENT; ENERGY INTAKE; ETAT CORPOREL; EXPERIMENTACION IN VITRO; EXPERIMENTATION IN VITRO; FATTY ACIDS; Fatty Acids, Nonesterified - blood; FEED INTAKE; Female; Fundamental and applied biological sciences. Psychology; GRASA DE LA LECHE; GRAZING; HEMOLIPIDOS; Hydroxybutyrates - blood; IN VITRO EXPERIMENTATION; INGESTION DE NUTRIENTES; INGESTION DE PIENSOS; INGESTION DE SUBSTANCES NUTRITIVES; Lactation - physiology; LIPID CONTENT; LIPIDE SANGUIN; MATIERE GRASSE DU LAIT; MILK FAT; MILK PROTEIN; MILK YIELD; NO PASTOREO; NUMERATION CELLULAIRE SOMATIQUE; NUTRIENT INTAKE; PASTOREO; PATURAGE; PESO CORPORAL; PIENSOS COMPLETOS; POIDS CORPOREL; PRISE ALIMENTAIRE (ANIMAUX); PROTEIN CONTENT; PROTEINAS DE LA LECHE; PROTEINE DU LAIT; RENDEMENT LAITIER; RENDIMIENTO LECHERO; SOMATIC CELL COUNT; TENEUR EN LIPIDES; TENEUR EN MATIERE SECHE; TENEUR EN PROTEINES; Terrestrial animal productions; VACAS LECHERAS; VACHE LAITIERE; Vertebrates; ZERO GRAZING
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.S0022-0302(98)75704-2

We compared the intakes of nutrients by high producing Holstein cows consuming pasture or a full nutrient positive control ration (total mixed ration; TMR) and identified nutrients that limited the milk production of cows consuming the high quality pasture. Cows (n = 8) were adapted to an all pasture diet by incrementally reducing the amount of TMR fed over a 4-wk period. A control group of cows (n = 8) remained in confinement and was fed a TMR. The performance of grazing cows differed significantly from that of cows fed the TMR in dry matter (DM) intake (19.0 vs. 23.4 kg/d of DM), milk production (29.6 vs. 44.1 kg/d), milk protein content (2.61% vs. 2.80%), live weight (562 vs. 597 kg), and body condition score (2.0 vs. 2.5). The high quality of the pasture permitted cows to consume the same daily intakes of neutral detergent fiber and crude protein (kilograms per day) as cows fed the TMR, but the pasture provided 19% less DM, organic matter, and net energy for lactation. Predictions using National Research Council estimates and the Cornell Net Carbohydrate and Protein System model indicated that the supply of metabolizable energy was first-limiting for the milk production of cows consuming high quality pasture rather than the supply of metabolizable protein or amino acids. Although a daily intake of 19 kg of DM was achieved on spring pasture, the significant mobilization of energy reserves indicated that supplemental energy is required to achieve milk production greater than 30 kg/d from high producing Holstein cows on intensive grazing systems