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An assessment of the energy requirements of the pregnant ewe using plasma free fatty acid concentrations

Published online by Cambridge University Press:  27 March 2009

J. J. Robinson
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen, AB2 9SB
C. Fraser
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen, AB2 9SB
C. Bennett
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen, AB2 9SB

Summary

An experiment was conducted in which 57 North Country Cheviot ewes, bearing variable foetal loads, were offered different amounts of feed intake during the latter half of gestation. Plasma free fatty acid (FFA) concentrations were estimated at 10-day intervals during the last 55 days of gestation. From the relationship between FFA concentration, energy intake, lamb birth weight and ewe body weight, estimates of the energy requirements of the pregnant ewe were predicted.

The additional metabolizable energy (ME) intake above maternal maintenance required to prevent elevation of plasma FFA concentrations above a predetermined basal level 5 days pre-partum was calculated as 335 kcal/kg lamb birth weight.

The results obtained from the use of plasma FFA concentrations in assessing the energy requirements of the pregnant ewe are discussed in relation to those obtained by other methods.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1971

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