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A note on the effects of body fatness and level of food intake on the rate of fat loss in lactating ewes

Published online by Cambridge University Press:  02 September 2010

R. T. Cowan ,
J. J. Robinson  and
I. McDonald
R. T. Cowan
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
J. J. Robinson
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
I. McDonald
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
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Abstract

Data from three comparative slaughter experiments involving a total of 73 ewes were used to study the influence of body fat content at the start of lactation (X1 kg) and of metabolizable energy intake (X2, MJ/day), on the rate of loss of body fat by lactating ewes over the first 6 weeks of lactation (Y, g/day). The relationship was described by the equation:

Thus the rate of fat loss was greater for ewes with higher initial fat contents, but the differential became less as metabolizable energy intake increased. Since increases in body fatness depress food intake it was not possible to prevent loss of body fat during early lactation in fat ewes given high concentrate diets ad libitum. The likely response in milk yield to increase in body fatness at parturition is therefore strongly dependent on the relative levels of body fatness and metabolizable energy intake. The value of any improvement in condition of the ewe at parturition may be considerable when metabolizable energy intake during lactation is low but much less when it is expected to be high.

Type
Research Article
Information
Animal Production , Volume 34 , Issue 3 , June 1982 , pp. 355 - 357
Copyright
Copyright © British Society of Animal Science 1982

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References

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