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The voluntary intake and digestibility of oat straw by pregnant beef cows as influenced by urea and phosphorus supplementation contained in molassed sugar-beet pulp

Published online by Cambridge University Press:  27 March 2009

G. Fishwick
Affiliation:
Glasgow UniversityVeterinary School, Bearsden, Glasgow
J. Fraser
Affiliation:
Glasgow UniversityVeterinary School, Bearsden, Glasgow
R. G. Hemingway
Affiliation:
Glasgow UniversityVeterinary School, Bearsden, Glasgow
J. J. Parkins
Affiliation:
Glasgow UniversityVeterinary School, Bearsden, Glasgow
N. S. Ritchie
Affiliation:
Glasgow UniversityVeterinary School, Bearsden, Glasgow

Summary

Pregnant beef heifers allowed ad libitum access to oat straw were given 2·7 kg molassed sugar-beet pulp alone or with additional dicalcium phosphate or urea or a combination of both materials in a Latin square design involving four feeding periods each of 21 days. Supplementation with urea to increase the total daily intake of digestible crude protein from about 130 to 290 g/day increased straw consumption by 20%. This increased the total intake of metabolizable energy from about 13 to 15 Meal/day. Increasing the total intake of phosphorus from about 6 to about 17 g P/day did not increase straw intake or digestibility or the total intake of metabolizable energy in either the presence or absence of additional urea.

Supplementation with urea increased the concentration of urea and glucose in the blood plasma and the concentration of ammonia in the rumen liquor, but did not increase the concentrations or alter the proportions of rumen volatile fatty acids. Addition of urea tended to increase the digestibility of the dry matter and crude fibre of the straw. Phosphorus supplementation increased the concentration of phosphorus in the blood plasma.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1974

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References

REFERENCES

Agricultural Research Council (1965). The Nutrient Requirements of Farm Livestock. No. 2. Ruminants. London: H.M.S.O.Google Scholar
Campling, R. C., Freer, M. & Balch, C. C. (1962). Factors influencing the voluntary intake of food by cattle. 3. The effect of urea on the voluntary intake of oat straw. British Journal of Nutrition 16, 115–24.CrossRefGoogle Scholar
Elliott, R. C. & Topps, J. H. (1963). Voluntary intake of low protein diets by sheep. Animal Production 5, 269–76.Google Scholar
Fishwick, G., Hemingway, R. G., Parkins, J. J. & Ritchie, N. S. (1973). A note of the effect of urea contained in a molassed sugar beet cube on the voluntary intake and digestibility of oat straw by steers. Animal Production 17, 205–8.Google Scholar
Fishwick, G. & Hemingway, R. G. (1973 a). Urea phosphate and mono-ammonium phosphate as dietary supplements for sheep fed diets inadequate in phosphorus and nitrogen. Journal of Agricultural Science, Cambridge 81, 139–43.CrossRefGoogle Scholar
Fishwick, G. & Hemingway, R. G. (1973 b). Magnesium phosphates as dietary supplements for growing sheep. Journal of Agricultural Science, Cambridge 81, 441–4.CrossRefGoogle Scholar
Fiske, C. H. & Subbarow, Y. (1925). The colorimetric determination of phosphorus. Journal of Biological Chemistry 66, 375400.CrossRefGoogle Scholar
Hemingway, R. G., MacPherson, A., Duthie, Alison K. & Brown, Nora H. (1968). The mineral composition of hay and silage grown in Scotland in relation to the A.R.C. standards for the mineral requirements of dairy cattle. Journal of Agricultural Science, Cambridge 71, 53–9.CrossRefGoogle Scholar
Hemingway, R. G. (1971). Minerals in the nutrition of hill cattle and sheep. Proceedings of the Nutrition Society 30, 221–9.CrossRefGoogle ScholarPubMed
Itaya, K. & Ui, M. (1965). Colorimetric determination of free fatty acids in biological fluids. Journal of Lipid Research 6, 1620.CrossRefGoogle ScholarPubMed
Kay, M., Andrews, R. P., MacLeod, N. A. & Walker, T. (1968). Urea and cereals as supplements for ruminants offered barley straw. Animal Production 10, 171–5.Google Scholar
Kleiber, M., Goss, H. & Guilbert, H. R. (1936). Phosphorus metabolism, deficiency and food utilisation in beef heifers. Journal of Nutrition 12, 121–53.CrossRefGoogle Scholar
Little, D. A. (1968). The effect of phosphorus in the diet on the intake of Townsville lucerne by cattle. Proceedings of the Australian Society of Animal Production 7, 376–80.Google Scholar
Mahadevan, V. & Stenroos, L. (1967). Quantitative analysis of volatile fatty acids in aqueous solution by gas chromatography. Analytical Chemistry 39, 1652–4.CrossRefGoogle ScholarPubMed
Playne, M. J. (1969). The effect of dicalcium phosphate supplements on the intake and digestibility of Townsville lucerne and spear grass by sheep. Australian Journal of Experimental Agriculture and Animal Husbandry 9, 192–5.CrossRefGoogle Scholar
Reinhold, J. G. (1953). Standard Methods in Clinical Chemistry, vol. I (ed. Reiner, M.), p. 83. New York: Academic Press.Google Scholar
Waite, R. & Wilson, Agnes G. (1968). The composition of rumen fluid from cows fed biuret and urea. Journal of Dairy Research 35, 203–12.CrossRefGoogle Scholar
Werner, W., Rey, H. G. & Wielinger, H. (1970). Properties of a new chromogen for the determination of glucose in blood by the GOD-POD method. Zeitschrift für analytische Chemie 252, 224–5.CrossRefGoogle Scholar