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Prediction of voluntary intake of grass silages by lactating cows offered concentrates at a flat rate

Published online by Cambridge University Press:  02 September 2010

A. J. Rook
Affiliation:
AFRC Institute of Grassland and Environmental Research, Hurley, Maidenhead SL6 5LR
M. Gill
Affiliation:
AFRC Institute of Grassland and Environmental Research, Hurley, Maidenhead SL6 5LR
R. D. Willink
Affiliation:
AFRC Institute of Grassland and Environmental Research, Hurley, Maidenhead SL6 5LR
S. J. Lister
Affiliation:
AFRC Institute of Grassland and Environmental Research, Hurley, Maidenhead SL6 5LR
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Abstract

Data for individually recorded silage dry-matter intake (SDMI), concentrate dry-matter intake (CDMI), live weight, milk yield and milk composition of lactating dairy cows offered silage ad libitum and concentrates on a flat-rate basis, together with data for silage composition from experiments conducted at four sites, were used to obtain simple and multiple regressions of SDMI on other variables.

Simple regressions showed that the most important variables affecting SDMI were, in order of importance: silage ammonia nitrogen, fat yield, CDMI, silage digestible organic matter concentration (DOMD) and live weight. The best multiple regression for the mean SDMI over weeks 4 to 13 of lactation accounted for proportionately 0·649 of the variation. Examination of week by week data for weeks 3 to 20 of lactation showed that two models for early and mid lactation were required to give a reasonable pattern of residual variances. These models accounted for 0·627 and 0·581 of the variation respectively. It was necessary to fit time effects explicitly in early lactation. Live weight was best represented by fitting post-calving live weight and deviations from post-calving live weight separately. A number of models requiring fewer input variables were also obtained to allow for use in situations where the full range of measurements is not made.

The new models were tested using independent data from three sites. They performed better than a number of previously published models but the best model still gave a prediction error of proportionately 0·17 about the mean actual silage intake in early lactation and 015 in late lactation.

The results suggest that there is little to be gained from further refinement of the functional form of the models and that the construction of a number of models for specific food and management situations is preferable to the use of global models.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1991

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References

REFERENCES

Agricultural Research Council. 1980. The Nutrient Requirements of Ruminant Livestock. Commonwealth Agricultural Bureaux, Slough.Google Scholar
Bartlett, M. S. 1937. Some examples of statistical methods of research in agriculture and applied biology. Journal of the Royal Statistical Society, Supplement 4, pp. 158159.Google Scholar
Bibby, J. and Toutenburg, H. 1977. Prediction and Improved Estimation in Linear Models. Ch. 1.5.4. Wiley, London.Google Scholar
Bines, J. A., Napper, D. J. and 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 Scholar
Brigstocke, T. D. A., Lindeman, M. A., Cuthbert, N. H., Wilson, P. N. and Cook, J. P. L. 1982. A note on the dry-matter intake of Jersey cows. Animal Production 35: 285287.Google Scholar
Chandler, P. T. and Walker, H. W. 1972. Generation of nutrient specifications for dairy cattle for computerized least cost ration formulation. Journal of Dairy Science 55: 17411749.CrossRefGoogle Scholar
Chatterjee, S. and Price, B. 1977. Regression Analysis by Example. Wiley, New York.Google Scholar
Cochrane, D. and Orcutt, G. H. 1949. Application of least squares regression to relationships containing autocorrelated error terms. Journal of the American Statistical Association 44: 3261.Google Scholar
Cook, R. D. 1977. Detection of influential measures in linear regression. Technometrics 19: 1518.Google Scholar
Curran, M. K., Wimble, R. H. and Holmes, W. 1970. Prediction of the voluntary intake of food by dairy cows. 1. Stall-fed cows in late pregnancy and early lactation. Animal Production 12: 195212.Google Scholar
Demarquilly, C. 1973. Chemical composition, fermentation characteristics, digestibility and voluntary intake of forage silages: change compared to initial green forages. Annales de Zootechnie 22: 199218.Google Scholar
Dewar, W. A. and McDonald, P. 1961. Determination of dry matter in silage by distillation with toluene. Journal of the Science of Food and Agriculture 12: 790795.CrossRefGoogle Scholar
Durbin, J. and Watson, G. S. 1951. Testing for serial correlation in least squares regression I. Biometrika 37: 409428.Google Scholar
Federation of United Kingdom Milk Marketing Boards. 1988. United Kingdom Dairy Facts and Figure 1988. Milk Marketing Board, Thames Ditton.Google Scholar
Forbes, J. M. 1977. Development of a model of voluntary food intake and energy balance in lactating cows. Animal Production 24: 203214.Google Scholar
Forbes, J. M. 1983. Models for the prediction of food intake and energy balance in dairy cows. Livestock Production Science 10: 149157.Google Scholar
Garnsworthy, P. C. and Topps, J. H. 1982. The effect of body condition of dairy cows at calving on their food intake and performance when given complete diets. Animal Production 35: 113119.Google Scholar
Gordon, F. J. 1984. The effect of level of concentrate supplementation given with grass silage during the winter on the total lactation performance of autumncalving dairy cows. Journal of Agricultural Science, Cambridge 102: 163179.Google Scholar
Gordon, F. J. 1989. An evaluation through lactating cattle of a bacterial inoculant as an additive for grass silage. Grass and Forage Science 44: 169179.CrossRefGoogle Scholar
Haigh, P. M. and Hopkins, J. R. 1977. Relationship between oven and toluene dry matter in grass silage. Journal of the Science of Food and Agriculture 28: 477480.Google Scholar
Lewis, M. 1981. Equations for predicting silage intake by beef and dairy cattle. Proceedings of the Sixth Silage Conference, Edinburgh, pp. 3536.Google Scholar
Milk Marketing Board. 1987. Milk Costs 1986-87, Booklet 2. Feed Use and Grassland Production for the Dairy Herd. MMB, Thames Ditton.Google Scholar
Ministry of Agriculture Fisheries and Food. 1975. Energy allowances and feeding systems for ruminants. Technical Bulletin 33. Her Majesty's Stationery Office, London.Google Scholar
Monteiro, L. S. 1972. The control of appetite in lactating cows. Animal Production 14: 263281.Google Scholar
Neal, H. D. St C., Thomas, C. and Cobby, J. M. 1984. Comparison of equations for predicting voluntary intake by dairy cows. Journal of Agricultural Science, Cambridge 103: 110.CrossRefGoogle Scholar
Phipps, R. H., Bines, J. A. and Cooper, A. 1983. A preliminary study to compare individual feeding through Calan electronic feeding gates to group feeding. Animal Production 36: 544 (Abstr.).Google Scholar
Phipps, R. H., Sutton, J. D., Weller, R. F. and Bines, J. A. 1987. The effect of concentrate composition and method of silage feeding on intake and performance of lactating dairy cows. Journal of Agricultural Science, Cambridge 109: 337343.Google Scholar
Phipps, R. H., Weller, R. F. and Bines, J. A. 1987. The influence of forage quality and concentrate level on dry matter intake and milk production of British Friesian heifers. Grass and Forage Science 42: 4958.Google Scholar
Rook, A. J., Dhanoa, M. S. and Gill, M. 1990. Prediction of the voluntary intake of grass silages by beef cattle. 2. Principal component and ridge regression analyses. Animal Production 50: 439454.Google Scholar
Rook, A. J. and Gill, M. 1990. Prediction of the voluntary intake of grass silages by beef cattle. 1. Linear regression analyses. Animal Production 50: 425438.Google Scholar
Sloan, B. K., Rowlinson, P. and Armstrong, D. G. 1988. The influence of a formulated excess of rumen degradable protein or undegradable protein on milk production in dairy cows in early lactation. Animal Production 46: 1322.Google Scholar
Small, J. 1986. An evaluation through dairy cows of systems of harvesting grass for silage and the response in milk production to source of supplementary protein. Ph.D. Thesis, Queen's University, Belfast.Google Scholar
Stakelum, G. and Connolly, J. 1987. Effect of body size and milk yield on intake of fresh herbage by lactating dairy cows indoors. Irish Journal of Agricultural Research 26: 922.Google Scholar
Thomas, C. 1987. Factors affecting substitution rates in dairy cows on silage based rations. Proceedings 21st Nottingham Feed Manufacturers Conference, pp. 205218.Google Scholar
Thomas, C., Aston, K. and Daley, S. R. 1985. Milk production from silage. 3. A comparison of red clover with grass silage. Animal Production 41: 2331.Google Scholar
Thomas, C., Aston, K., Tayler, J. C., Daley, S. R. and 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 Production 32: 285295.Google Scholar
Thomas, C., Daley, S. R., Aston, K. and 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. and Reid, J. T. 1965. Prediction of the energy value of cows' milk. Journal of Dairy Science 48: 12151223.Google Scholar
Vadiveloo, J. and Holmes, W. 1979. The prediction of the voluntary feed intake of dairy cows. Journal of Agricultural Science. Cambridge 93: 553562.CrossRefGoogle Scholar
Wilkins, R. J., Hutchinson, K. J., Wilson, R. F. and Harris, C. E. 1971. The voluntary intake of silage by sheep. 1. Interrelationships between silage composition and intake. Journal of Agricultural Science, Cambridge 11: 531537.CrossRefGoogle Scholar
Wood, P. D. P. 1967. Algebraic model of the lactation curve in cattle. Nature, London 216: 164165.CrossRefGoogle Scholar
Yungblut, D. H., Stone, J. B., Macleod, G. K., Grieve, D. G. and Burnside, E. B. 1981. The development of feed intake prediction equations for lactating dairy cows. Canadian Journal of Animal Science 61: 151157.Google Scholar