Hostname: page-component-7479d7b7d-c9gpj Total loading time: 0 Render date: 2024-07-13T16:57:37.688Z Has data issue: false hasContentIssue false
  • English
  • Français

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
Get access

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Agricultural Research Council. 1980. The Nutrient Requirements of Ruminant Livestock. Commonwealth Agricultural Bureaux, Slough.Google Scholar
Atkinson, T., Fowler, V. R., Garton, G. A. and Lough, A. K. 1972. A rapid method for the accurate determination of lipid in animal tissues. Analyst, Lond. 97: 562–568.CrossRefGoogle ScholarPubMed
Cowan, R. T. 1980. Changes in body composition of ruminants during early lactation. Ph.D. Thesis. Univ. Aberd.Google Scholar
Cowan, R. T., Reid, G. W., Greenhalgh, J. F. D. and Tait, C. A. G. 1981a. Effects of feeding level in late pregnancy and dietary protein concentration during early lactation on food intake, milk yield, liveweight change and nitrogen balance of cows. J. Dairy Res. 48: 201–212.CrossRefGoogle ScholarPubMed
Cowan, R. T., Robinson, J. J., Greenhalgh, J. F. D. and Mchattie, I. 1979. Body composition changes in lactating ewes estimated by serial slaughter and deuterium dilution. Anim. Prod. 29: 81–90.Google Scholar
Cowan, R. T., Robinson, J. J., McDonald, I. and Smart, R. 1980. Effects of body fatness at lambing and diet in lactation on body tissue loss, feed intake and milk yields of ewes in early lactation. J. agric. Sci., Camb. 95: 497–514.CrossRefGoogle Scholar
Cowan, R. T., Robinson, J. J., Mchattie, I. and Pennie, K. 1981b. Effects of protein concentration in the diet on milk yield, change in body composition and th e efficiency of utilization of body tissues for milk production in ewes. Anim. Prod. 33: 111–120.Google Scholar