The development of maintenance energy requirement and energetic efficiency for lactation from production data of lactating dairy cows

2002 ◽  
Vol 2002 ◽  
pp. 39-39
Author(s):  
R. E. Agnew ◽  
T. Yan ◽  
J. J. Murphy ◽  
C. P. Ferris ◽  
F. J. Gordon
Keyword(s):  
Dairy Cows ◽  
Western Europe ◽  
Energy Requirement ◽  
Energetic Efficiency ◽  
Production Data ◽  
Lactating Dairy Cows ◽  
Short Period ◽  
Metabolisable Energy ◽  
Maintenance Energy Requirement ◽  
Feeding Systems

The energy feeding systems currently adopted for dairy cows in Western Europe and North America were developed from calorimetric data published 30 years ago. However, the calorimetric measurements were usually undertaken with a small number of trained animals, housed for a short period in respiration chambers. The objective of the present study was to use production data to develop the metabolisable energy (ME) requirement for maintenance (MEm) and the efficiency of ME use for lactation (kl) for dairy cows.

The use of production data of feeding studies in lactating dairy cows to validate energy feeding systems

2002 ◽  
Vol 2002 ◽  
pp. 102-102
Author(s):  
T. Yan ◽  
R. E. Agnew ◽  
J. J. Murphy ◽  
C. P. Ferris ◽  
F. J. Gordon
Keyword(s):  
Dairy Cows ◽  
Production Data ◽  
Net Energy ◽  
Calorimetric Data ◽  
Production Studies ◽  
Lactating Dairy Cows ◽  
Metabolisable Energy ◽  
Using Data ◽  
Feeding Systems

There is little information available in the literature on the validation of the currently adopted energy feeding systems developed from calorimetric data, using data obtained in production studies. The objective of the present study was to use production data from feeding studies to validate some metabolisable energy (ME) systems (AFRC, 1990 and 1993; SCA, 1990) and net energy (NE) systems (Van Es, 1978, INRA, 1989; NRC, 2001).

scholarly journals Effect of nutrition on the GH responsiveness of liver and adipose tissue in dairy cows

2007 ◽  
Vol 195 (1) ◽  
pp. 49-58 ◽  
Author(s):  
R P Rhoads ◽  
J W Kim ◽  
M E Van Amburgh ◽  
R A Ehrhardt ◽  
S J Frank ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Dairy Cows ◽  
Energy Requirement ◽  
Energy Deficit ◽  
Regulatory Subunit ◽  
Early Lactation ◽  
Similar Reduction ◽  
Lactating Dairy Cows ◽  
Igf I ◽  
Maintenance Energy Requirement

Dairy cows enter a period of energy insufficiency after parturition. In liver, this energy deficit leads to reduced expression of the liver-specific GH receptor transcript (GHR1A) and decreased GHR abundance. As a consequence, hepatic processes stimulated by GH, such as IGF-I production, are reduced. In contrast, adipose tissue has been assumed to remain fully GH responsive in early lactation. To determine whether energy insufficiency causes contrasting changes in the GH responsiveness of liver and adipose tissue, six lactating dairy cows were treated for 4 days with saline or bovine GH when adequately fed (AF, 120% of total energy requirement) or underfed (UF, 30% of maintenance energy requirement). AF cows mounted robust GH responses in liver (plasma IGF-I and IGF-I mRNA) and adipose tissue (epinephrine-stimulated release of non-esterified fatty acids in plasma, IGF-I mRNA, and p85 regulatory subunit of phosphatidylinositol 3-kinase mRNA). Reductions of these responses were seen in the liver and adipose tissue of UF cows and were associated with decreased GHR abundance. Reduced GHR abundance occurred without corresponding reductions of GHR1A transcripts in liver or total GHR transcripts in adipose tissue. In contrast, undernutrition did not alter the abundance of proteins involved in the early post-receptor signaling steps. Thus, a feed restriction reproducing the energy deficit of early lactation depresses GH actions not only in liver but also in adipose tissue. It remains unknown whether a similar reduction of GH action occurs in the adipose tissue of early lactating dairy cows.

The use of regression techniques on calorimetric data to estimate the metabolisable energy requirements of lactating dairy cows

1997 ◽  
Vol 1997 ◽  
pp. 4-4
Author(s):  
T. Yan ◽  
F. J. Gordon ◽  
R. E. Agnew ◽  
M. G. Porter ◽  
D. C. Patterson
Keyword(s):  
Dairy Cows ◽  
Open Circuit ◽  
Energy Requirements ◽  
Gaseous Exchange ◽  
Calorimetric Data ◽  
Grass Silage ◽  
Lactating Dairy Cows ◽  
Holstein Friesian ◽  
Regression Techniques ◽  
Metabolisable Energy

The metabolisable energy (ME) requirement for maintenance (MEm) can be determined by measuring the fasting metabolism of the non-lactating cow, but this approach cannot encompass any differences in maintenance metabolic rate between lactating and non-lactating animals. The MEm and efficiency of ME use for lactation (k1) can also be estimated by regression of energy outputs against ME intake (MEI). During 1992 to 1995, a total of 221 Holstein/Friesian lactating dairy cows, which were offered grass silage-based diets, were subjected to gaseous exchange measurements in indirect open-circuit respiration calorimeters. The objective of the present study was to use these data to predict the MEm and k1 by a range of regression techniques for lactating dairy cows offered grass silage-based diets.

Rationale of feeding systems for lactating dairy cows

1990 ◽  
Vol 57 (2) ◽  
pp. 151-164 ◽  
Author(s):  
C. Lewis Johnson ◽  
C. Lang Tran
Keyword(s):  
Integral Equation ◽  
Dairy Cows ◽  
Time Course ◽  
Equation Approach ◽  
Lactating Dairy Cows ◽  
Integral Equation Approach ◽  
Biological Concepts ◽  
Feeding Regimen ◽  
Lactation Cycle ◽  
Feeding Systems

SummaryManipulations of the lactation cycle are achieved through nutritional regimens and generally result in a restriction of the physiological lactation cycle. Most models of lactation used in management programmes only describe the average time course of lactation for groups of cows on a given feeding regimen. This is inadequate for the variety of feeding systems in use on British farms. In the present paper several existing models of lactation have been critically evaluated. An integral equation approach has been developed to rationalize experimental observations and currently accepted biological concepts.

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