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Complete diets for dairy cows: the effect of energy concentration and change in energy concentration of a complete diet on intake and performance of lactating dairy cows

Published online by Cambridge University Press:  27 March 2009

R. H. Phipps
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading, RG2 9AT
J. A. Bines
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading, RG2 9AT
R. F. Weller
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading, RG2 9AT
Joanne Thomas
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading, RG2 9AT

Summary

Ninety-two British Friesians (56 cows and 36 heifers) were divided into two groups during weeks 3–10 of lactation and received ad libitum either complete diet H (65% concentrates, 35% grass silage, 11·7 MJ ME/kg D.M.) or diet M (50% concentrates, 50% grass silage, 11·2 MJ ME/kg D.M.). In weeks 11· 20 half the animals of each group continued to receive the same diet (HH or MM) while the other half were changed from diet H to M (HM) or from diet M to L (ML). Diet L contained 35% concentrates, 65% grass silage and 10·7 MJ ME/kg D.M. The crude protein concentration of all diets was maintained at about 157 g/kg D.M. by the addition of soya-bean meal to diets M and L.

During weeks 3–10 the mean D.M. intake (kg/day), milk yield (kg/day), milk protein (g/kg) and live-weight change (kg/day) for animals on diets H and M were 15·0, 21·7, 33·3, 0·50 and 12·9, 20·2, 31·5, 0·35 respectively. Differences were significant for D.M. intake, milk yield and milk protein concentration. Although milk-fat concentration of cows given diet H (40·2 g/kg) was similar to that of cows given diet M (39·9 g/kg), heifers receiving diet H had a significantly lower value (37·0 g/kg) than those given diet M (39·8 g/kg).

When animals were changed from diet H to M or from M to L at week 11, D.M. intake, milk yield and milk-protein concentration decreased. However, milk-fat concentration and live-weight change were generally unaffected.

During the complete experimental period, weeks 3–20, animals on treatments HH, HM, MM and ML had mean D.M. intakes and milk yields of 15·3, 14·2, 13·2, 12·4 kg/day and 19·7, 18·5, 17·8, 17·0 kg/day. Milk-protein concentration, was closely related to D.M. intake, but only with heifers did diet H significantly depress milk-fat concentration. The highest live-weight gain was recorded on treatment HH (0·40 kg/day) and the lowost on treatment ML (0·29 kg/day) with intermediate values for treatments HM and MM.

In vivodigestibility coefficients of D.M. and organic matter for diet H (0·731, 0·757) were significantly higher than those of diet L (0·707, 0·734) with intermediate values for diet M. However, for acid-detergent fibre the digestibility coefficient for diet H was significantly lower (0·562) than for diet L (0·662). The digestibility coefficients for nitrogen in all three diets were similar.

Estimates of mean efficiency of utilization of ME for lactation were made on a weekly basis and were 0·56 and 0·64 for animals on diets H and M in weeks 3·10. During weeks 11·20 the mean values for animals on treatments HH, HM, MM and ML were 0·46, 0·53, 0·51 and 0·59, respectively.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1984

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References

REFERENCES

Akinyele, I. O. & Spahr, S. L. (1975). Stage of lactation as a criterion for switching cows from one complete feed to another during early lactation. Journal of Dairy Science 58, 917921.Google Scholar
Bines, J. A. (1980). Dairy cows: the case for complete diet feeding. Span 23, 1113.Google Scholar
Coppock, C. E. (1977). Feeding methods and group systems. Journal of Dairy Science 60, 13271336.CrossRefGoogle Scholar
Coppock, C. E., Noller, C. H. & Wolfe, S. A. (1974). Effect of forage-concentrate ratio in complete feeds fed ad libitum on energy intake in relation to requirements by dairy cows. Journal of Dairy Science 57, 13711380.Google Scholar
Escano, J. R. & Rusoff, L. L. (1973). Varying energy in a complete feed for high producing cows. Journal of Dairy Science 56, 11441148.Google Scholar
Everson, R. A., Jorgensen, N. A., Crowley, J. W., Jensen, E. L. & Barrington, G. P. (1976). Input output of dairy cows fed a complete ration of a constant or variable forage-to-grain ratio. Journal of Dairy Science 59, 17761787.Google Scholar
Gill, M. (1979). The principles and practice of feeding ruminants on complete diets. Grass and Forage Science 34, 155161.Google Scholar
Harner, J. P. & Spahr, S. L. (1971). Effect of energy concentration and stage of lactation on intake of dairy cows fed mixed rations of concentrates and silage. Journal of Dairy Science 54, 782 (Abstract).Google Scholar
Johnson, C. L. (1983). Influence of feeding pattern on the biological efficiency of high-yielding dairy cows. Journal of Agricultural Science, Cambridge 100, 191199.CrossRefGoogle Scholar
Kroll, O. (1983). The moisture content and roughage source in complete diets for dairy cows. Animal Production 36, 506 (Abstract).Google Scholar
Mccullouqh, M. E. (1972). Factors to consider when building complete rations for dairy cows. Proceedings of the Maryland Nutrition Conference, pp. 16.Google Scholar
Mccullough, M. E. (1973). Optimum Feeding of Dairy Animals. Athens, Georgia, U.S.A.: University of Georgia Press.Google Scholar
Marshall, S. P. & Voigt, A. R. (1975). Complete rations for dairy cattle. 1. Methods of preparation and roughage-to-concentrate ratios of blended rations with corn silage. Journal of Dairy Science 58, 891895.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
Ministry Of Agriculture, Fisheries And Food (1977). Complete Diet Feeding of Dairy Cows. London: Agricultural Development and Advisory Service.Google Scholar
Ministry Of Agriculture, Fisheries And Food (1979). Complete Diet Feeding of Dairy Cows. Supplementary report on investigations carried out during 1978–1979. London: Agricultural Development and Advisory Service.Google Scholar
Moseley, J. E., Coppock, C. E. & Lake, G. B. (1976). Abrupt changes in the forage–concentrate ratios of complete feeds fed ad libitum to dairy cows. Journal of Dairy Science 59, 14711483.Google Scholar
Owen, J. B. (1979). Complete diet feeding of dairy cows. In Recent Advances in Animal Nutrition(ed. Haresign, W. and Lewis, D.), pp. 159171. London: Butterworth.Google Scholar
Phipps, R. H., Bines, J. A., Fulford, R. J. & Weller, R. F. (1984). Complete diets for dairy cows: a comparison between complete diets and separate ingredients. Journal of Agricultural Science, Cambridge 103. 171180.CrossRefGoogle Scholar
Sims, J. A. (1972). Complete lactation responses of cows to ad libitum feeding of complete feeds. Journal of Dairy Science 55, 688 (Abstract).Google Scholar
Smith, N. E., Ufford, G. R., Coppock, C. E. & Merrill, W. G. (1978). One group versus two group system for lactating cows fed complete rations. Journal of Dairy Science 61, 11381145.Google Scholar