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Feeding and milk fat production

Published online by Cambridge University Press:  27 February 2018

J. D. Sutton*
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading RG2 9AT
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Extract

Decreasing the proportion of long forage in mixed diets from 400 to 100 g/kg at constant digestible energy intakes reduces milk fat content by approximately 5 g/kg for every 100 g/kg decrease in hay. This response varies widely and a safe minimum diet composition to maintain approximately 40 g fat/kg milk from Friesian cows in mid-lactation is approximately 450 g long forage/kg or 220 g acid-detergent fibre/kg dry matter. This, however, would reduce milk yields. With barley-based concentrates, milk yield increases as the proportion of hay in the diet is reduced, with the result that the reduction in the yield of fat is less than the fall in its concentration. Milk fat content is higher when ground maize, which is a slowly fermented starch source, or fodder beet or fibrous by-products replace rapidly fermented starch sources such as barley in low-roughage diets. Milk yield, however, is lower. Supplementary fats and oils generally increase milk yield but their effects on milk fat content and yield vary widely.

Increasing the intake of high-concentrate diets of fixed composition increases the yield of milk but reduces its fat content. Increasing the number of meals per 24 h reduces this milk fat depression without affecting milk yield. Thus, advice on milk fat production must take account of the level of intake, the pattern of feeding and the diet composition.

In most situations, the avoidance of low milk fat content requires control of rumen fermentation to prevent high proportions of propionic acid. However, with frequent feeding during the 24 h, high propionic acid in the rumen has less effect on milk fat. It appears that high plasma insulin concentration is the main factor reducing milk fat production.

The release of insulin is stimulated by the peaks of propionate, which are produced after large meals of concentrates but not by the steady supply of propionate associated with frequent feeding.

Available knowledge can permit wide variation in milk fat production by dietary manipulation with reasonable accuracy but the future aim should be for more direct intervention at metabolic control points.

Type
Research Article
Copyright
Copyright © British Society of Animal Production 1984

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References

REFERENCES

Balch, C. C., Balch, D. A., Bartlett, S., Hosking, Zena D., Johnson, V. W., Rowland, S. J. and Turner, Jill. 1955. Studies of the secretion of milk of low fat content by cows on diets low in hay and high in concentrates. V. The importance of the type of starch in the concentrates. J. Dairy Res. 22: 1015.Google Scholar
Balch, C. C., Broster, W. H., Rook, J. A. F. and Tuck, Valerie J. 1965. The effect on growth rate and on milk yield and composition of finely grinding the hay and cooking (flaking) the maize in mixed diets for growing and for milking heifers. J. Dairy Res. 32: 111.Google Scholar
Banks, W., Clapperton, J. L., Kelly, Morag E., Wilson, Agnes G. and Crawford, R. J. M. 1980. The yield, fatty acid composition and physical properties of milk fat obtained by feeding soya oil to dairy cows. J. Sci. Fd Agric. 31: 368374.Google Scholar
Banks, W., Clapperton, J. L. and Steele, W. 1983. Dietary manipulation of the content and fatty acid composition of milk fat. Proc. Nutr. Soc. 42: 399406.Google Scholar
Bines, J. A., Brumby, P. E., Storry, J. E., Fulford, Rosemary J. and Braithwaite, G. D. 1978. The effect of protected lipids on nutrient intakes, blood and rumen metabolites and milk secretion in dairy cows during early lactation. J. agric. Sci., Comb. 91: 135150.Google Scholar
Broster, W. H., Sutton, J. D. and Bines, J. A. 1979. Concentrate: forage ratios for high-yielding dairy cows. In Recent Advances in Animal Nutrition—1978 (ed. Haresign, W. and Lewis, D.), pp. 99126. Butterworth, London.Google Scholar
Broster, W. H., Sutton, J. D., Smith, T., Broster, Valerie J. and Balch, C. C. 1970. The effect of supplements of sucrose and of glucose monohydrate on the milk production and live weight of dairy cows. J. agric. Sci., Camb. 74: 217225.CrossRefGoogle Scholar
Brumby, P. E., Storry, J. E. and Sutton, J. D. 1972. Metabolism of cod-liver oil in relation to milk fat secretion. J. Dairy Res. 39: 167182.Google Scholar
Burt, A. W. A. and Dunton, C. R. 1967. Effect of frequency of feeding upon food utilization by ruminants. Proc. Nutr. Soc. 26: 181190.Google Scholar
Davis, C. L. and Brown, R. E. 1970. Low-fat milk syndrome. In Physiology of Digestion and Metabolism in the Ruminant (ed. Phillipson, A. T.), pp. 545565. Oriel Press, Newcastle upon Tyne.Google Scholar
Davis, C. L., Grenawalt, D. A. and McCoy, G. C. 1983. Feeding value of pressed brewers' grains for lactating dairy cows. J. Dairy Sci. 66: 7379.Google Scholar
de Visser, H. and de Groot, A. A. M. 1981. The influence of the starch and sugar content of concentrates on feed intake, rumen fluid, production and composition of milk. In Metabolic Disorders in Farm Animals (ed. Giesecke, D., Dirksen, G. and Stangassinger, M.), pp. 4148. Veterinary Institute, University of Munich, Munich.Google Scholar
Flatt, W. P., Moe, P. W., Hooven, N. W., Lehmann, R. P., Ørskov, E. R. and Hemken, R. W. 1969. Energy utilization by high producing dairy cows. 1. Experimental design, ration composition, digestibility data, and animal performance during energy balance trials. In Energy Metabolism of Farm Animals (ed. Baxter, K. L., Kielanowski, J. and Thorbek, Greta), pp. 221234. Oriel Press, Newcastle upon Tyne.Google Scholar
Hart, I. C. 1983. Endocrine control of nutrient partition in lactating ruminants. Proc. Nutr. Soc. 42: 181194.Google Scholar
Kaufmann, W., Rohr, K., Daenicke, R. and Hagemeister, H. 1975. [Experiments on the influence of the frequency of feeding on rumen fermentation, food intake and milk yield.] Ber. Landw. Sonderh. 191: 269295.Google Scholar
Kirchgessner, M., Müller, H. L. and Schwarz, F. J. 1982, Experimental studies on the feeding frequency of dairy cows. In Energy Metabolism of Farm Animals (ed. Ekern, A. and Sundstøl, F.), pp. 3033. Agricultural University of Norway, Aas-NLH.Google Scholar
Krohn, C. C. and Andersen, P. E. 1979. [Rations with beet or barley fed separately or in complete rations for dairy cows.] Beretn. St. Husdyrbrugsforsøg, 480.Google Scholar
MacGregor, C. A., Stokes, M. R., Hoover, W. H., Leonard, H. A., Junkins, L. L. Jr., Sniffen, C. J. and Mailman, R. W. 1983. Effect of dietary concentration of total nonstructural carbohydrate on energy and nitrogen metabolism and milk production of dairy cows. J. Dairy Sci. 66: 3950.Google Scholar
Oldham, J. D., Broster, W. H., Napper, D. J. and Siviter, J. W. 1979. The effect of a low-protein ration on milk yield and plasma metabolites in Friesian heifers during early lactation. Br. J. Nutr. 42: 149162.Google Scholar
Oldham, J. D. and Smith, T. 1982. Protein-energy interrelationships for growing and for lactating cattle. In Protein Contribution of Feedstuffs for Ruminants: Application to Feed Formulation (ed. Miller, E. L., Pike, I. H. and van Es, A. J. H.), pp. 103130. Butterworth, London.Google Scholar
Ørskov, E. R., Grubb, D. A. and Kay, R. N. B. 1977. Effect of postruminal glucose or protein supplementation on milk yield and composition in Friesian cows in early lactation and negative energy balance. Br. J. Nutr. 38: 397405.Google Scholar
Palmquist, D. L. and Jenkins, T. C. 1980. Fat in lactation rations: review. J. Dairy Sci. 63: 114.Google Scholar
Schingoethe, D. J. 1976. Whey utilization in animal feeding: a summary and evaluation. J. Dairy Sci. 59: 556570.Google Scholar
Storry, J. E. 1981. The effect of dietary fat on milk composition. In Recent Advances in Animal Nutrition—1981 (ed. Haresign, W.), pp. 333. Butterworth, London.Google Scholar
Storry, J. E., Brumby, P. E., Hall, A. J. and Johnson, V. W. 1974. Responses in rumen fermentation and milk-fat secretion in cows receiving low-roughage diets supplemented with protected tallow. J. Dairy Res. 41: 165173.Google Scholar
Sutton, J. D. 1984. The digestion and absorption of energy substrates in the lactating cow. J. Dairy Sci. In press.Google Scholar
Sutton, J. D., Bines, J. A., Napper, D. J., Willis, J. M. and Schuller, E. 1984. Form of carbohydrate in dairy concentrates: effects on milk production and hay intake. Rep. natn. Inst. Res. Dairy., 1983. In press.Google Scholar
Sutton, J. D., Hart, I. C. and Broster, W. H. 1982. The effect of feeding frequency on energy metabolism in milking cows given low-roughage diets. In Energy Metabolism of Farm Animals (ed. Ekern, A. and Sundstøl, F.), pp. 2629. Agricultural University of Norway, Aas-NLH.Google Scholar
Sutton, J. D., Oldham, J. D. and Hart, I. C. 1980. Products of digestion, hormones and energy utilization in milking cows given concentrates containing varying proportions of barley or maize. In Energy Metabolism (ed. Mount, L. E.), pp. 303306. Butterworth, London.CrossRefGoogle Scholar
Thomas, C. 1984. Milk compositional quality and the rôle of forages. In Milk Compositional Quality and its Importance in Future Markets (ed. Castle, M. E. and Gunn, R. G.), Occ. Publ. Br. Soc. Anim. Prod., No. 9.Google Scholar
van der Honing, Y., Wieman, B. J., Steg, A. and van Donselaar, B. 1981. The effect of fat supplementation of concentrates on digestion and utilization of energy by productive dairy cows. Neth. J. agric. Sci. 29: 7992.Google Scholar