Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-25T08:01:17.553Z Has data issue: false hasContentIssue false
  • English
  • Français

Undernutrition in sheep. Nitrogen repletion by N-depleted sheep

Published online by Cambridge University Press:  09 March 2007

F. D. DeB. Hovell ,
E. R. Ørskov ,
D. J. Kyle  and
N. A. MacLeod
F. D. DeB. Hovell
Affiliation:
Rowett Research Institute, Buckshurn, Aberdeen AB2 9SB
E. R. Ørskov
Affiliation:
Rowett Research Institute, Buckshurn, Aberdeen AB2 9SB
D. J. Kyle
Affiliation:
Rowett Research Institute, Buckshurn, Aberdeen AB2 9SB
N. A. MacLeod
Affiliation:
Rowett Research Institute, Buckshurn, Aberdeen AB2 9SB
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

1. Wether lambs of 29–44 kg live-weight, totally nourished by the infusion of volatile fatty acids (VFA) into the rumen and casein into the abomasum, were given five treatments in consecutive periods. The treatments were (daily amounts per kg live weight (W)0.75): (a) high-protein for 7 d (2500 mg nitrogen, 650 kJ VFA); (b) low-protein for 7–15 d (525 mg N, 650 kJ VFA); (c) N-free for 7 d (no N, 450 kJ VFA); (d) very-low-protein for 24–28 d (300 mg N, 400 kJ VFA); (e) high-protein for 40 d (2500 mg N, 650 kJ VFA). Nine lambs were subjected to treatments (a), (b) and (c) (Expt 1) and four of the lambs additionally received treatments (d) and (e) (Expt 2).

2. In Expt 1 all nine lambs had a positive N retention on treatment (a) but abrupt change to treatment (b) resulted in substantial negative N balances initially, and a period of approximately 5 d adaptation was required before N equilibrium was re-established. Animals again exhibited negative N balances when the N-free infusion (treatment c) was introduced and during that period there was no evidence of adaptation. Basal urinary N excretion was estimated to be 356 (SE 12) mg N/kg W0.75.

3. In Expt 2 all four lambs were depleted of N when receiving the very-low-protein treatment (d). The progressively decreasing N losses recorded during days 1 to 12 of the treatment period were slightly greater than those recorded during days 13 to 28 but the difference between the means was not significant (P > 0.05). There was no evidence of an adaptation in N retention between days 13 and 28 of the treatment. As assessed during days 13 to 28 of the treatment the efficiency of utilization of infused casein N was 1.0; this compared with a value of 0.66 recorded during treatment (b) in Expt 1. Live weight loss during the period of N depletion was 101 (SE 27) g/d.

4. When lambs were given treatment (e) during the last period of Expt 2, N repletion was rapid and complete within a few days. Ten days after the introduction of the treatment the rate of N retention was estimated to be 1019 (SE 38) mg/kg W0.75 per d and this value declined at a rate of 9.5 (SE 1.9) mg N/kg W0.76 per d for the following 30 d. In comparison, N retention determined for the high-protein treatment in Expt 1 was 724 (SE 66) mg N/kg W0.75 per d. Live-weight gains during N repletion were 292 (SE 26) g/d.

5. It is concluded that N-depleted lambs can replete rapidly and that enhanced N accretion (compensatory growth) may persist for 4–5 weeks. If the improved efficiency of utilization of infused N observed during N depletion reflects a changed basal N requirement, the validity of simple factorial systems for estimating N requirement is called into question.

Type
Papers on General Nutrition
Information
British Journal of Nutrition , Volume 57 , Issue 1 , January 1987 , pp. 77 - 88
Copyright
Copyright © The Nutrition Society 1987

References

REFERENCES

Agricultural Research Council (1980). The Nutrient Requirement of Ruminant Livestock. Farnham Royal: Commonwealth Agricultural Bureaux.Google Scholar
Agricultural Research Council (1984). The Nutrient Requirementts of Ruminant Livestock, Supplement no. 1. Farnham Royal: Commonwealth Agricultural Bureaux.Google Scholar
Allden, W. G. (1970). Nutrition Abstracts and Reviews 110, 1167–1184.Google Scholar
Engelhardt, W. V. (1970). In Physiology of Digestion of Metabolism in the Ruminant, Proceedings of the 3rd International Symposium, Cambridge, pp. 132–146 [Phillipson, A. T., editor]. Newcastle upon Tyne: Oriel Press.Google Scholar
Engelhardt, W. V. & Hauffe, R. (1975). In Digestion and Metabolism in the Ruminant, Proceedings 4th International Symposium, Sydney, Australia, pp. 216–230 [McDonald, I. W. and Warner, A. C. I., editors]. Armidale, NSW, Australia: University of New England Publishing Unit.Google Scholar
Fattet, I., Hovell, F. D. DeB., Ørskov, E. R., Kyle, D. J., Pennie, K. & Smart, R. I. (1984). British Journal of Nutrition 52, 561–574.CrossRefGoogle Scholar
Golden, M., Waterlow, J. C. & Picou, D. (1977). American Journal of Clinical Nutrition 30, 1345–1348.CrossRefGoogle Scholar
Hovell, F. D. DeB., Ørskov, E. R., Grubb, D. A. & MacLeod, N. A. (1983 a). British Journal of Nutrition 50, 173–187.CrossRefGoogle Scholar
Hovell, F. D. DeB., Ørskov, E. R., MacLeod, N. A. & McDonald, I. (1983 b). British Journal of Nutrition 50, 331–343.CrossRefGoogle Scholar
MacLeod, N. A., Corrigall, W., Stirton, R. A. & Ørskov, E. R. (1982). British Journal of Nutrition 47, 547–552.CrossRefGoogle Scholar
Millward, D. J., Garlick, P. J., Stewart, J. C. R., Nanyelgo, D. O. & Waterlow, J. C. (1975). Biochemical Journal 150, 235–243.CrossRefGoogle Scholar
Ørskov, E. R., Grubb, D. A., Wenham, G. & Corrigall, W. (1979). British Journal of Nutrition 41, 553–558.CrossRefGoogle Scholar
Ørskov, E. R., McDonald, I., Grubb, D. A. & Pennie, K. (1976). Journal of Agricultural Science, Cambridge 86, 411–423.CrossRefGoogle Scholar
Ørskov, E. R., MacLeod, N. A., Fahmy, S., Istasse, L. & Hovell, F. D. DeB. (1983). British Journal of Nutrition 50, 99–107.CrossRefGoogle Scholar
Reid, J. T. & White, O. D. (1977). Proceedings of the Cornell Conference for Feed Manufacturers, pp. 16–17.Google Scholar
Storm, E., Ørskov, E. R. & Smart, R. I. (1983). British Journal of Nutrition 50, 471–478.CrossRefGoogle Scholar
Waterlow, J. C., Garlick, P. J. & Millward, D. J. (1978). Protein Turnover in Mammalian Tissues and in the Whole Body. Amsterdam: North Holland Publishing Co.Google Scholar
Wilson, P. N. & Osbourn, D. F. (1960). Biological Reviews 35, 324–363.CrossRefGoogle Scholar