The Effect of Energy Supplementation on Intake and Utilisation Efficiency of Urea-treated Low-quality Roughage in Sheep I. Rumen Digestion and Feed Intake

  • Migwi, P.K. (University of New England, School of Rural Science & Environment) ;
  • Godwin, I. (University of New England, School of Rural Science & Environment) ;
  • Nolan, J.V. (University of New England, School of Rural Science & Environment) ;
  • Kahn, L.P. (University of New England, School of Rural Science & Environment)
  • Received : 2010.08.07
  • Accepted : 2010.12.20
  • Published : 2011.05.01


Inefficient rumen microbial fermentation is a major factor limiting intake of low quality roughage in ruminants. In this study, the effect of energy supplementation on rumen microbial fermentation, absorption of balanced digestion products and voluntary feed intake in sheep was investigated. A basal diet of a urea-treated mixture of wheaten chaff and barley straw (3:1 DM) containing 22.2 g N/kg DM was used. Four Merino-cross wethers weighing $45{\pm}4.38\;kg$ and fitted with permanent rumen and abomasal cannulae were allocated to four treatments in a $4{\times}4$ Latin square design. The dietary treatments were basal diet ($E_0$), or basal diet supplemented with sucrose (112.5 g/d) administered to the animals intra-ruminally ($E_R$), abomasally ($E_A$), or through both routes (50:50) ($E_{RA}$). Feed intake (basal and dietary) was increased (p<0.05) by sucrose supplementation through the rumen ($E_R$) or abomasum ($E_A$). However, there was no difference (p>0.05) in intake between animals on the control diet and those supplemented with sucrose through both intraruminal and abomasal routes ($E_{RA}$). The digestibility of DM and OM was highest in $E_R$ and $E_A$ supplemented animals. Although the rumen pH was reduced (p<0.001) in animals supplemented with sucrose entirely intra-ruminally ($E_R$), the in sacco degradation of barley straw in the rumen was not adversely affected (p>0.05). Intra-ruminal sucrose supplementation resulted in a higher concentration of total VFA, acetate and butyrate, while the pattern of fermentation showed a higher propionate: acetate ratio. Intra-ruminal supplementation also increased (p<0.05) the glucogenic potential (G/E) of the absorbed VFA. However, there was no difference (p>0.05) in microbial protein production between the four dietary treatments. Protozoa numbers were increased (p<0.05) by intra-ruminal supplementation of sucrose.


Roughage;Energy Supplementation;Intake;Glucogenic Potential;Microbial Protein;Purine Derivatives


  1. AFRC. 1993. Technical committee on responses to nutrients, energy and protein requirements of ruminants. An Advisory Manual. CAB International, Wallingford UK.
  2. AOAC. 1990. Official methods of analysis. Association of Official Analytical Chemists, Washington DC.
  3. ARC. 1984. Agricultural research council: The Nutrient Requirements of Ruminant Livestock (Suppl. 1), CAB, Slough, UK.
  4. Balcells, J., J. A. Guada, C. Castrillo and J. Gasa. 1991. Urinary excretion of allantoin and allantoin precursors by sheep after different rates of purine infusion into the duodenum. J. Agric. Sci. 11:309-317.
  5. Beitz, J. A. 1974. Micro-Kjeldahl analysis by an improved automated ammonia determination following manual digestion. Anal. Chem. 46:1617-1618.
  6. Bird, S. H. and R. A. Leng. 1984. Further studies on the effects of the presence or absence of protozoa in the rumen on live-weight and wool growth of sheep. Br. J. Nutr. 52:607-611.
  7. Bird, S. H., M. K Hill and R. A. Leng. 1979. The effects of defaunation of the rumen on the growth of lambs on low-protein high-energy diets. Br. J. Nutr. 42:81-87.
  8. Blaxter, K. L. 1967. The energy metabolism in ruminants (2nd Edition). Hutchinson Scientific and Technical, London.
  9. Bonsi, M. L. K., P. O. Osuji, I. V. Nsahlai and A. K. Tuah. 1994. Graded levels of Sesbania sesban and Leucaena leucocephala as supplement of teff straw given to Ethiopian Menz sheep. Anim. Prod. 59:235-244.
  10. Brockman, R. P. 1993. Glucose and short-chain fatty acid metabolism. In: Quantitative Aspects of Ruminant Digestion and Metabolism (Ed. J. M. Forbes and J. France). pp. 249-265. (CAB International, Cambridge, UK).
  11. Chen, X. B. and M. J. Gomez. 1992. Estimation of microbial protein supply to sheep and cattle based on urinary excretion of purine derivatives-an overview of the technical details. Occasional publication, Rowett Research Institute, Aberdeen, Scotland.
  12. Chen, X. B. and F. B. Hovell. 1996. Measurements of roughage or protein degradation using polyester bag 'in sacco' technique, Help file (Manual), Rowett Research Institute, Aberdeen, UK.
  13. Chen, X. B., E. R. Orskov and F. D. Hovell. 1990. Excretion of purine derivatives by ruminants: endogenous excretion, differences between cattle and sheep. Br. J. Nutr. 63:121-129.
  14. Cloete, S. W. P. and N. M. Kritzler. 1984. Urea ammoniation compared to urea supplementation as a method of improving the nutritive value of wheat straw for sheep. S. Afric. J. Anim. Sci. 14:59-63.
  15. Cloete, S. W. P., T. T. De villers and N. M. Kritzler. 1983. The effect of ammoniation by urea on the nutritive value of wheat straw for sheep. S. Afric. J. Anim. Sci. 13(3):143-146.
  16. Crook, W. M. and W. E. Simpson. 1971. Determination of ammonium in Kjeldahl digests of crops by automated procedure. J. Sci. Food Agric. 22:9-10.
  17. Djajanegara, A. and P. T. Doyle. 1989. Urea supplementation compared with pretreatment 1. Effects on intake, digestion and live weight change by sheep fed rice straw. Anim. Feed Sci. Technol. 27:17-30.
  18. Egan, A. R. 1977. Nutritional status and intake regulation in sheep. VIII. Relationship between the voluntary intake of herbage and protein/energy ratio in the digestion products. Aust. J. Agric. Res. 28:907-915.
  19. Erwin, E. S., G. J. Macro and E. M. Emery. 1961. Volatile fatty acid analysis of blood and rumen fluid by gas chromatography. J. Dairy Sci. 44:1768-1771.
  20. Ferrell, C. L., K. K. Kreikmeremeier and H. C. Freetly. 1999. The effect of supplementing energy, nitrogen and protein on feed intake, digestibility, and nitrogen flux across the gut and liver in sheep fed low-quality forage. J. Anim. Sci. 77:3353-3364.
  21. Fonseca, A. J. M., A. A. Dias-da-Silava and A. L. G. Laurenco. 2001. Effect of maize and citrus pulp supplementation of urea-treated wheat straw on intake and productivity in female lambs. J. Anim. Sci. 73:123-136.
  22. France, J. and R. C. Siddons. 1993. Volatile fatty acid production. In: Quantitative Aspects of Ruminant Digestion and Metabolism (Ed. J. M. Forbes and J. France). pp. 107-121. CAB International, Cambridge, UK.
  23. Habib, G. 1988. Manipulation of rumen fermentation and supplementation of diet to improve productivity of ruminants. PhD Thesis, University of New England, Armidale.
  24. Hoover, W. H. 1986. Chemical factors involved in ruminal fibre digestion. J. Dairy Sci. 69:2755-2766.
  25. Iwanyanwu, I. E. J., N. N. Umunna and N. I. Dim. 1990. Effects of urea supplement with or without molasses on the intake, digestibility and live weight change of beef heifers fed native hay. Anim. Feed Sci. Technol. 31:277-284.
  26. Kay, R. N. B. 1969. Digestion of protein in the small intestines of adult ruminants. Proc. Nutr. Soc. 28:140-151.
  27. Khan, L. P., D. Ouellet and J. V. Nolan. 2001. Estimation of allantoin flux using continuous infusion of [$^{14}C$] allantoin: Sensitivity to plasma loading with unlabelled allantoin. Br. J. Nutr. 86:691-696.
  28. Lechner-Doll, M., M. Kaske and W. V. Engelhardt. 1991. Factors affecting the minimum retention time (MRT) of particles in the fore-stomach of ruminants and camelids. In: Physiological Aspects of Digestion and Metabolism in Ruminants (Ed. T. Tsuda, Y. Sasaki and R. Kawashima). pp. 455-475. (Academic Press, Sydney).
  29. Lee, G. J., D. W. Hennessy, J. V. Nolan and R. A. Leng. 1987. Response to nitrogen and maize supplements by young cattle offered low quality pasture hay. Aust. J. Agric. Res. 38:195-207.
  30. Leng, R. A. 1970. Formation and production of volatile fatty acids in the rumen. In: Physiology of Digestion and Metabolism in the Ruminant (Ed. A. T. Phillipson). pp. 406-421. Oriel Press, Newcastle Upon Tyne, UK.
  31. Leng, R. A. 1982. Modification of rumen fermentation: In: Nutritional Limits to Animal Production from Pastures. Proceedings International Symposium, University of Queensland (Ed. J. B. Hacker). CAB International. pp. 427-453.
  32. Luther, R., A. Trenkle and W. Burroughs. 1966. Influence of rumen protozoa on volatile fatty acids production and ration digestibility in lambs. J. Anim. Sci. 25:1116-1121.
  33. Kariya, R., Z. Morita, R. Oura and J. Sekine. 1989. The in vitro study on the rates of starch consumption and volatile fatty acid production by rumen with or without ciliates. Japanese J. Zootechnical Sci. 144:102-112.
  34. Mackie, R. I., F. M. Gilchrist, A. M. Robberts, P. E. Hannah and H. M. Schwatz. 1978. Microbiological and chemical changes in the rumen during the stepwise adaptation of sheep to high concentrate diets. J. Agric. Sci. 90:241-254.
  35. Mould, F. L. and E. R. Orskov. 1983. Manipulation of rumen fluid pH and its influence on cellulolysis in sacco, DM degradability and rumen microflora of sheep offered hay or concentrate. Anim. Feed Sci. Technol. 10:1-14.
  36. Mould, F. L., E. R. Orskov and S. O. Mann. 1983. Associative effects of mixed feeds. I. Effects of type and level of supplementation and the influence of the rumen pH on cellulolysis, in vivo dry matter digestion of various roughages. Anim. Feed Sci. Technol. 10:15-30.
  37. Newbold, C. J., D. J. Chamberlain and A. G. Williams. 1986. The role of protozoa in lactic acidosis. Proceedings of the 6th International Conference on Production on Disease in Farm Animals, Queens University, Belfast. pp. 154-157.
  38. NRC. 1988. National research council: Nutrients Requirements of Dairy Cattle (6th Ed), National Academy Press, Washington, DC.
  39. Obara, Y., D. W. Dellow and J. V. Nolan. 1991. The influence of energy on nitrogen kinetics in ruminants. In: Physiological Aspects and Digestion and Metabolism in Ruminants (Ed. T. Tsuda, Y. Sasaki and R. Kawashima). pp. 515-539 (Academic Press, Sydney).
  40. Orskov, E. R. 1986. Starch digestion and utilization in ruminants. J. Anim. Sci. 63:1624-1633.
  41. Orskov, E. R. and I. McDonald. 1979. The estimation of protein degradability in the rumen from incubation measurements weighted according to rate of passage. J. Agric. Sci. 92:499-503.
  42. Orskov, E. R., R. W. Mayes and S. O. Mann. 1972. Postruminal digestion of sucrose in sheep. Br. J. Nutr. 28:425-432.
  43. Perdock, H. B. and R. A. Leng. 1989. Rumen ammonia requirements for efficient digestion and intake of straw in cattle. In: The Roles of Protozoa and Fungi in Ruminant Digestion (Ed. J. V. Nolan, R. A. Leng and D. I. Demeyer). pp. 291-293 (Penambul Books, Armidale, Australia).
  44. Preston, T. R. and R. A. Leng. 1987. Matching ruminant production systems with available resources in the tropics and subtropics (Penambul Books, Armidale, Australia).
  45. Rook, J. A., N. H. Lee and D. J. Armstrong. 1987. The effect of intraruminal infusions of urea, casein, glucose syrup, and a mixture of casein and glucose syrup on N digestion in the rumen of cattle receiving grass silage diets. Br. J. Nutr. 57:89-98.
  46. Royes, J. B., W. F. Brown, F. G. Martin and D. B. Bates. 2001. Source and level of energy supplementation for yearling cattle fed ammoniated hay. J. Anim. Sci. 79:1313-1321.
  47. Russell, J. B. and H. J. Strobel. 1993. Microbial energetics. In: Quantitative Aspects of Ruminant Digestion and Metabolism (Ed. J. M. Forbes and J. France). pp. 165-185 (CAB International, Cambridge, UK).
  48. Russell, J. B. and D. B. Wilson. 1996. Why are ruminal cellulolytic bacteria unable to digest cellulose at low pH? J. Dairy Sci. 79:1503-1509.
  49. Ryan, B. F., B. L. Joiner and T. A. Rayan. 1985. Minitab Handbook (2nd Ed), PWS Publishers, Boston, USA.
  50. Satter, L. D. and L. L. Slyter. 1974. Effect of ammonia concentration on rumen microbial protein production in vitro. Br. J. Nutr. 32:199-208.
  51. Siddons, R. C. 1968. Carbohydrase activities in the bovine digestive tract. Biochem. J. 108:839.
  52. Siddons, R. C., C. Arricateres, D. L. Gale and D. E. Beever. 1984. The effect of formaldehyde or glutaraldehyde application to Lucerne before ensiling on silage fermentation and silage N digestion in sheep. Br. J. Nutr. 52:391-401.
  53. Sutherland, T. M. 1976. The overall metabolism of nitrogen in the rumen. In: Reviews in Rural Science, Number II (Ed. T. M. Sutherland, J. R. McWilliams and R. A. Leng). pp. 65-72 (University of New England, Armidale, Australia).
  54. Syrjala, L. 1972. Effect of different sucrose, starch and cellulose supplements on the utilization of grass silages by ruminants. Annales Agric. Fennie 11:199-276.
  55. Ulyatt, M. J., D. W. Dellow, A. John, C. S. W. Reid and G. C. Waghorn. 1986. Contribution of chewing during eating and rumination to the clearance of digesta from the ruminoreticulum. In: Control of Digestion and Metabolism in Ruminants (Ed. L. P. Milligan, W. L. Grovum and A. Dobson). pp. 498-515. Prentice-Hall, New Jersey.
  56. Wolin, M. J. 1981. Fermentation in the rumen and human large intestines. Sci. 213:1463-1468.