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Comparison of equations for predicting voluntary intake by dairy cows

Published online by Cambridge University Press:  27 March 2009

Heather D. St. C. Neal
Affiliation:
The Grassland Research Institute, Hurley, Maidenhead, Berkshire
C. Thomas
Affiliation:
The Grassland Research Institute, Hurley, Maidenhead, Berkshire
J. M. Cobby
Affiliation:
The Grassland Research Institute, Hurley, Maidenhead, Berkshire

Summary

Rations for dairy cows are often formulated using predictions of voluntary feed intake calculated from regression equations. The accuracy of the predictions of dry-matter intake by seven equations is investigated. Comparisons are made when live weight is taken to be the observed weekly mean (MLW), the observed live weight after calving (CLW) or an estimated breed weight accompanied by a notional pattern of live-weight change (BLW). Data recorded on a British Friesian dairy herd at the Grassland Research Institute fed mostly silage ad libitum and various supplements are used. The mean square prediction error (MSPE) is calculated for each week and summarized over the whole experimental period.

The least MSPE's are 2·1, 2·8 and 2·4 (kg D.M.)2 for comparisons using MLW, CLW and BLW respectively. The Ministry of Agriculture, Fisheries and Food (1975) equation involving only live weight and milk yield performs well and would be useful when only the limited measurements of live weight and milk yield are available, but the more complex equations of Vadiveloo & Holmes (1979) and of Lewis (1981) give consistently the best predictions. The importance of using the original definitions of the variables when applying a predictive equation is illustrated. Even so, the large errors found in the predictions of intake points to the need for further research.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1984

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References

Agricultural Research Council (1980). The Nutrient Requirements of Ruminant Livestock. Slough: Commonwealth Agricultural Bureaux.Google Scholar
Aston, K., Daley, S. R. & Tayler, J. C. (1979). Maize silage for milk production: the influence of concentrate supplementation and the effect of adding urea or ammonia before feeding. Animal Production 29, 163173.Google Scholar
Bibby, J. & Toutenburg, H. (1977). Prediction and Improved Estimation in Linear Models. Chapters 1. 5. 4. London: John Wiley and Sons.Google Scholar
Bines, J. A., Napper, D. J. & Johnson, V. W. (1977). Long term effects of level of intake and diet composition on the performance of lactating dairy cows. 2. Voluntary intake and ration digestibility in heifers. Proceedings of the Nutrition Society 36, 146A.Google ScholarPubMed
Broster, W. H. & Thomas, C. (1982). The influence of level and pattern of concentrate input on milk output. In Recent Advances in Animal Nutrition — 1981 (ed. Haresign, W.), pp. 4969. London: Butterworths.Google Scholar
Forbes, J. M. (1983). Models for the prediction of food intake and energy balance in dairy cows. Livestock Production Science 10, 149157.CrossRefGoogle Scholar
Journet, M., Poutous, M. & Calomiti, S. (1965). Appétit de la vache laitière. Annales de Zoolechnie 14 (1), 538.CrossRefGoogle Scholar
Lewis, M. (1981). Equations for predicting silage intake by beef and dairy cattle. Proceedings of the Sixth Silage Conference, Edinburgh 1981, pp. 3536.Google Scholar
Milk Marketing Board (1982 a). Milk Costs 1980–81 Booklet 1. Economics and Physical Features of Dairy Herds. Thames Ditton, Surrey: Milk Marketing Board.Google Scholar
Milk Marketing Board (1982 b). UK Dairy Facts and Figures. Thames Ditton, Surrey: Milk Marketing Board.Google Scholar
Ministry of Agriculture, Fisheries and Food (1975). Energy Allowances and Feeding Systems for Ruminants. Technical Bulletin, no. 33. London: H.M.S.O.Google Scholar
Tayler, J. C. & Aston, K. (1976). Milk production from diets of silage and dried forage. 2. Effect of ensiling ryegrass cut at two levels of digestibility and fed ad libitum with supplements of dried grass pellets. Animal Production 23, 211221.Google Scholar
Tayler, J. C, Aston, K. & Daley, S. R. (1979). Milk production from diets of silage and dried forage. 3. Effect of formalin-treated ryegrass silage of high digestibility given ad libitum with and without urea. Animal Production 28, 171181.CrossRefGoogle Scholar
Theil, H. (1966). Applied Economic Forecasting. Chapter 2. Amsterdam: North Holland Publishing Company.Google Scholar
Thomas, C, Aston, K., Tayler, J. C, Daley, S. R. & Osbourn, D. F. (1981). Milk production from silage. 1. The influence of an additive containing formaldehyde and formic acid on the response of lactating heifers and cows to supplementary protein. Animal Prcduction 32, 285295.Google Scholar
Thomas, C, Daley, S. R., Aston, K. & Hughes, P. M. (1981). Milk production from silage. 2. The influence of the digestibility of silage made from the primary growth of perennial ryegrass. Animal Production 33, 713.Google Scholar
Tyrrell, H. F. & Reid, J. T. (1965). Prediction of the energy of cows' milk. Dairy Science 48, 12151222.CrossRefGoogle Scholar
Vadiveloo, J. & Holmes, W. (1979). The prediction of the voluntary feed intake of dairy cows. Journal of Agricultural Science, Cambridge 93, 553562.CrossRefGoogle Scholar
Wood, P. D. P. (1969). Factors affecting the shape of the lactation curve in cattle. Animal Production 11, 307316.Google Scholar