Effects of feed restriction on milk production and metabolism in mid-lactation dairy cows
type: CreativeWork
description: Availability of glucose precursors and a proper interorgan coordination during the metabolic cascade of adaptations occurring during periods of lower DMI, are the vital importance to achieve a successful transition from late gestation to lactation. The aim of the study was to determine metabolic responses to a short-term period of negative energy balance induced by feed restriction (FR) and the effect of abomasal supplementation of different amino acids (AA) or glucose. Seven multiparous Holstein cows (93 ± 15 DIM) were randomly assigned to 7 treatments in a 7 × 4 incomplete Latin square design. In 6 treatments, daily DMI was restricted to provide 60% of energy requirements during 5 d; the 7th treatment consisted of ad libitum (AL) intake. Feed was provided once daily at 0900 h. Effects of FR (AL vs RC), day, time within day, and interactions were evaluated with ANOVA using the MIXED procedure of SAS. Evaluating the effect of FR, milk yield (P < 0.01), milk protein concentration (P = 0.03) and yield (P < 0.01), and lactose yield (P < 0.01) were lower for RC, whereas milk fat (P < 0.01) and urea N concentrations were higher (P < 0.01). Treatment RC induced lower plasma insulin (P = 0.01) and glucose (P = 0.04) concentrations, with quadratic (P < 0.01 for both) decreasing trends reaching nadir on d 3. Concentration of NEFA was higher (P < 0.01) and increased quadratically (P < 0.01) with its maximum on d 3 during FR. Serum BHBA increased linearly (P = 0.04) for RC (RC x d; P = 0.16) with its peak at d 4. Catabolism of amino acids (AA) increased early during FR as indicated by plasma urea N increasing (P < 0.01) quadratically (P < 0.01), with its peak on d 2 and decreasing afterward. Accounting for all the amino-N circulating in form of urea or eliminated in milk as MUN, the decrease in concentration of all the AA in circulation analyzed here was not sufficient for the amount of urea synthetized. Therefore, it seems probable that body tissue protein was rapidly mobiliz…
abstract: Availability of glucose precursors and a proper interorgan coordination during the metabolic cascade of adaptations occurring during periods of lower DMI, are the vital importance to achieve a successful transition from late gestation to lactation. The aim of the study was to determine metabolic responses to a short-term period of negative energy balance induced by feed restriction (FR) and the effect of abomasal supplementation of different amino acids (AA) or glucose. Seven multiparous Holstein cows (93 ± 15 DIM) were randomly assigned to 7 treatments in a 7 × 4 incomplete Latin square design. In 6 treatments, daily DMI was restricted to provide 60% of energy requirements during 5 d; the 7th treatment consisted of ad libitum (AL) intake. Feed was provided once daily at 0900 h. Effects of FR (AL vs RC), day, time within day, and interactions were evaluated with ANOVA using the MIXED procedure of SAS. Evaluating the effect of FR, milk yield (P < 0.01), milk protein concentration (P = 0.03) and yield (P < 0.01), and lactose yield (P < 0.01) were lower for RC, whereas milk fat (P < 0.01) and urea N concentrations were higher (P < 0.01). Treatment RC induced lower plasma insulin (P = 0.01) and glucose (P = 0.04) concentrations, with quadratic (P < 0.01 for both) decreasing trends reaching nadir on d 3. Concentration of NEFA was higher (P < 0.01) and increased quadratically (P < 0.01) with its maximum on d 3 during FR. Serum BHBA increased linearly (P = 0.04) for RC (RC x d; P = 0.16) with its peak at d 4. Catabolism of amino acids (AA) increased early during FR as indicated by plasma urea N increasing (P < 0.01) quadratically (P < 0.01), with its peak on d 2 and decreasing afterward. Accounting for all the amino-N circulating in form of urea or eliminated in milk as MUN, the decrease in concentration of all the AA in circulation analyzed here was not sufficient for the amount of urea synthetized. Therefore, it seems probable that body tissue protein was rapidly mobiliz…
author: Ansia Vazquez, Ivan
language: en
keywords: Amino acids, Negative energy balance
date published: 2018-03-13T15:44:35Z
date modified: 2026-07-22T22:24:37Z
provider: University of Illinois - Urbana-Champaign
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Illinois at Urbana-Champaign

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2142/99275