Hostname: page-component-8448b6f56d-42gr6 Total loading time: 0 Render date: 2024-04-16T19:48:40.527Z Has data issue: false hasContentIssue false
  • English
  • Français

The effects of intraruminal infusions of urea on the voluntary intake and milk production of cows receiving grass silage diets

Published online by Cambridge University Press:  01 June 2009

Jai-Jun Choung ,
David G. Chamberlain ,
Phillip C. Thomas  and
Ian Bradbury
Jai-Jun Choung
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK
David G. Chamberlain
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK
Phillip C. Thomas
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK
Ian Bradbury
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK
Get access Rights & Permissions [Opens in a new window]

Summary

Responses of dairy cows given silage diets to the intraruminal infusion of urea in progressively increasing doses were studied in four experiments, two with non-lactating cows and two with lactating cows. No clinical symptoms of NH3 toxicity were observed in any of the experiments. When urea was infused continuously, silage intake was depressed (P < 0·05) when the total supply of N exceeded the equivalent of 250g crude protein (CP)/kg DM in the total diet. However, when the urea load was administered twice daily, as opposed to continuously, intake depression (P < 0·05) occurred at the equivalent of 170g CP/kg DM. At the higher doses of urea, concentrations of NH3 in peripheral blood increased and were accompanied by increased concentrations of glucose and reduced levels of insulin in plasma. In general, responses of milk production followed those of silage intake but there was evidence of greater proportional reductions in the yield of lactose relative to that of fat and protein. It is concluded that the voluntary intake of high-protein silages may be depressed by factors associated with high rates of absorption of NH3 from the rumen.

Type
Original Articles
Information
Journal of Dairy Research , Volume 57 , Issue 4 , November 1990 , pp. 455 - 464
Copyright
Copyright © Proprietors of Journal of Dairy Research 1990

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Barej, W. & Harmeyer, J. 1979 Effect of hyperammonaemia on blood glucose and plasma insulin levels sheep. Quarterly Journal of Experimental Physiology 64 31–37CrossRefGoogle ScholarPubMed
Barej, W., Harmeyer, J., Drost, H. & Libau, H. 1982 The effect of hyperammonaemia on plasma glucose, insulin, glucagon and adrenaline levels in sheep. Zentralblatt für Veterinärmedzin A29 197–206CrossRefGoogle ScholarPubMed
Bartley, E. E., Avery, T. B., Nagaraja, T. G., Watt, B. R., Davidovich, A., Galitzer, S. & Lassman, B. 1981 Ammonia toxicity in cattle. V. Ammonia concentration of lymph and portal, carotid and jugular blood after ingestion of urea. Journal of Animal Science 53 494–498CrossRefGoogle ScholarPubMed
Chalmers, M. I., Grant, I. & White, F. 1976 Nitrogen passage through the wall of the ruminant digestive tract. In Protein Metabolism and Nutrition pp. 159–179 (Eds Cole, D. J. A., Boorman, K. N., Buttery, P. J., Lewis, D., Neale, R. J. & Swan, H.). London: ButterworthsGoogle Scholar
Chamberlain, D. G., Thomas, P. C. & Quig, J. 1986 Utilization of silage nitrogen in sheep and cows: amino acid composition of duodenal digesta and rumen microbes. EAAP Publication No. 16 Grass and Forage Science 41 31–38CrossRefGoogle Scholar
Emmanuel, B. & Edjtehadi, M. 1981 Glucose biokinetics in normal and urea-treated sheep (Ovis aries). Comparative Biochemistry and Physiology 68B 555–560Google Scholar
Fernandez, J. M., Croom, W. J., Johnson, A. D., Jaquette, R. D. & Edens, F. W. 1988 Subclinical ammonia toxicity in steers: effects on blood metabolite and regulatory hormone concentrations. Journal of Animal Science 66 3259–3266CrossRefGoogle ScholarPubMed
Flint, D. J., Sinnett-Smith, P. A., Clegg, R. A. & Vernon, R. G. 1979 Role of insulin receptors in the changing metabolism of adipose tissue during pregnancy and lactation in the rat. Biochemical Journal 182 421–427CrossRefGoogle ScholarPubMed
Gordon, F. J. 1989 An evaluation through lactating cattle of a bacterial inoculant as an additive for grass silage. Grass and Forage Science 44 169–179CrossRefGoogle Scholar
Kelly, N. C. & Thomas, P. C. 1978 The nutritive value of silages. Energy metabolism in sheep receiving diets of grass silage or grass silage and barley. British Journal of Nutrition 40 205–219CrossRefGoogle ScholarPubMed
Kertz, A. F., Koepke, M. K., Davidson, L. E., Betz, N. L., Norris, J. R., Skoch, L. V., Cords, B. R. & Hopkins, D. T. 1982 Factors influencing intake of high urea-containing rations by lactating dairy cows. Journal of Dairy Science 65 587–604CrossRefGoogle ScholarPubMed
Leonard, M. C., Buttery, P. J. & Lewis, D. 1977 The effects on glucose metabolism of feeding a high-urea diet to sheep. British Journal of Nutrition 38 455–462CrossRefGoogle ScholarPubMed
Lewis, D. & Buttery, P. J. 1972 Ammonia toxicity in ruminants. In Production Diseases in Farm Animals pp. 201–211 (Eds. Payne, J. M., Hibbit, K. G. & Sansom, B. F.). London: Ballière TindallGoogle Scholar
Newbold, C. J. 1985 Microbial metabolism of lactic acid in the rumen. PhD Thesis, University of GlasgowGoogle Scholar
Payne, R. W., Lane, P. W., Ainsley, H. E., Bricknell, K. E., Digby, P. G. N., Harding, S. A., Leeh, P. K., Simpson, H. R., Todd, A. P., Verrier, P. J. & White, R. P. 1987 Genstat 5 reference manual. Oxford: Clarendon PressGoogle Scholar
Symonds, H. W., Mather, D. L. & Collis, K. A. 1981 The maximum capacity of the liver of the adult dairy cow to metabolize ammonia. British Journal of Nutrition 46 481–486CrossRefGoogle ScholarPubMed
Thomas, P. C. & Chamberlain, D. G. 1989 Evaluation and prediction of the nutritional value of conserved forage and pasture. In Proceedings of the 50th Nottingham Easter School in Agricultural Science (in press)Google Scholar
Thomas, P. C. & Chamberlain, D. G. 1982 The utilization of silage nitrogen. In Forage Protein Conservation and Utilization pp. 121–146 (Eds Griffiths, T. W. & Maguire, M. F.). Brussels: Commission of the European CommunitiesGoogle Scholar
Thomas, P. C. & Kelly, M. E. 1976 The effect of frequency of feeding on milk secretion in the Ayrshire cow. Journal of Dairy Research 43 1–7CrossRefGoogle ScholarPubMed
Vernon, R. G., Clegg, R. A. & Flint, D. J. 1981 Metabolism of sheep adipose tissue during pregnancy and lactation. Adaptation and regulation. Biochemical Journal 200 307–314CrossRefGoogle ScholarPubMed