Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-15T11:16:09.543Z Has data issue: false hasContentIssue false
  • English
  • Français

Food intake and diet selection in sheep: the effect of manipulating the rates of digestion of carbohydrates and protein of the foods offered as a choice

Published online by Cambridge University Press:  09 March 2007

I. Kyriazakis  and
J. D. Oldham
I. Kyriazakis
Affiliation:
Genetics and Behavioural Sciences Department, Scottish Agricultural College Edinburgh, West Mains Road, Edinburgh EH9 3JG
J. D. Oldham
Affiliation:
Genetics and Behavioural Sciences Department, Scottish Agricultural College Edinburgh, West Mains Road, Edinburgh EH9 3JG
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.

An experiment was designed to investigate whether the degree of synchrony between the rates of digestion of carbohydrates and N of foods offered as a choice would have an effect, through their consequences, on the short- and long-term diet selection of sheep. Four foods (RL, RH, SL and SH) with the same high metabolizable energy, and similar high metabolizable protein contents were made into pellets. Foods RL and RH were based on a rapidly fermentable carbohydrate source and foods SL and SH on a slowly fermentable carbohydrate source; within each source one food (RL or SL) had a low, and the other (RH or SH) a high, men-degradable protein (RDP) content. The foods within a carbohydrate source were offered either singly or as a choice (RI/RH or SI/SH) to eleven rumen-fistulated mature sheep. The design was two 3 x 3 Latin squares (replicated once) with 5- week periods; squares consisted of two single foods and their respective choice. Weeks 1, 3 and 5 were considered to be controls, and weeks 2 and 4 used for remen infusions of either urea or fructose infused over 4h (10·00-14·00 hours). Food intake (FI) and diet selections (DS) were recorded daily and every 2 h (08·00-16·00 hours) on days 2-5 of each week; m e n pH and NH3 concentrations were also measured during these time intervals of day 5. As expected, feeding treatment affected significantly the rumen measurements: m e n NH3 concentrations were higher on foods RH and SH, and men pH lowest on RL. Daily FI was lowest on treatments SL and choice SI/ The mean daily proportion of the low-RDP food in the selected diet was lower when the carbohydrate source was rapidly (choice RI/RH) rather than slowly fermentable (choice SI/SH); this was consistent with the experimental hypothesis. Short-term infusions affected further rumen variables (in the expected directions), irrespective of feeding treatment. However, DS over the 4 h infusion period were unaffected; these short-term DS were consistent with the ones selected over the longer term (daily). The results suggest that the long-term (daily) diet selection of sheep may be affected by the degree of synchrony of energy and protein to the men. The fact that diet selections were not altered further by short-term manipulations of these supplies might reflect inadequacies of the methodology (infusions) adopted here.

Keywords

Diet selectionFood intakeRumenRumen-degradable proteinSheep
Type
Animal Nutrition
Information
British Journal of Nutrition , Volume 77 , Issue 2 , February 1997 , pp. 243 - 254
Copyright
Copyright © The Nutrition Society 1997

References

REFERENCES

Agricultural and Food Research Council (1992). Technical committee on responses of ruminant animals. Nutrition Abstracts and Reviews Series B62, 781–835.Google Scholar
Agricultural and Food Research Council (1993). Energy and Protein Requirements of Ruminants. Wallingford: CAB International.Google Scholar
Chamberlain, D. G. & Choung, J. J. (1995). The importance of rate of a ruminal fermentation of energy sources in diets for dairy cows. In Recent Advances in Animal Nutrition pp. 3–27 [Garnsworthy, P. C. and Cole, D. J. A. editors]. Nottingham: Nottingham University Press.Google Scholar
Cooper, S. D. B., Kyriazakis, I., Anderson, D. H. & Oldham, J. D. (1995 a). The ability of sheep to modify their feeding behaviour in order to counteract challenges to their rumen environment. Animal Science 60, 513.Google Scholar
Cooper, S. D. B., Kyriazakis, I. & Nolan, J. V. (1995 b). Diet selection in sheep: the role of the rumen environment in the selection of a diet from two foods that differ in their energy density. British Journal of Nutrition 74, 39–54.CrossRefGoogle ScholarPubMed
Cooper, S. D. B., Kyriazakis, I. & Oldham, J. D. (1994). The effect of late pregnancy on the diet selections made by ewes. Livestock Production Science 40, 263–275.CrossRefGoogle Scholar
Cropper, M. R. (1987). Growth and development of sheep in relation to feeding strategy. PhD Thesis, University of Edinburgh.Google Scholar
De Visser, H. (1993). Characterisation of carbohydrates in compound feeds. In Recent Advances in Animal Nutrition, pp. 19–38 [Garnsworthy, P. C. and Cole, D. J. A. editors]. Nottingham: Nottingham University Press.Google Scholar
Emmans, G. C. & Kyriazakis, I. (1995). The idea of optimisation in animals: uses and dangers. Livestock Production Science 44, 189–197.CrossRefGoogle Scholar
Engku Azahan, E. A. & Forbes, J. M. (1992). Effects of intraruminal infusions of sodium salts on seiection of hay and concentrate foods by sheep. Appetite 18, 143–154.CrossRefGoogle Scholar
Forbes, J. M. (1995). Voluntary Food Intake and Diet Selection in Farm Animals. Wallingford: CAB International.Google Scholar
Ketelaars, J. J. M. H. & Tolkamp, B. J. (1992). Toward a new theory of feed intake regulation in ruminants. 1. Causes of differences in voluntary feed intake: critique of current views. Livestock Production Science 30, 269–296.CrossRefGoogle Scholar
Krebs, J. R. & McCleery, R. H. (1984). Optimisation in behavioural ecology. In Behavioural Ecology-An Evolutionary Approach, pp. 91–121 [Krebs, J. R. and Davies, N. B. editors]. Oxford: Blackwell Scientific.Google Scholar
Kyriazakis, I. & Emmans, G. C. (1992). Selection of a diet by growing pigs given choices between foods differing in contents of protein and rapeseed meal. Appetite 19, 121–132.CrossRefGoogle ScholarPubMed
Kyriazakis, I. & Emmans, G. C. (1995). The voluntary feed intake of pigs given feeds based on wheat bran, dried citrus pulp and grass meal, in relation to measurements of feed bulk. British Journal of Nutrition 73, 191–207..CrossRefGoogle ScholarPubMed
Kyriazakis, I. & Oldham, J. D. (1993). Diet selection in sheep: the ability of growing lambs to select a diet that meets their crude protein requirements. British Journal of Nutrition 69, 617–629.CrossRefGoogle Scholar
Newman, J. A., Penning, P. A., Parsons, A. J., Harvey, A. & Orr, R. J. (1994). Fasting affects intake behaviour and diet preference of grazing sheep. Animal Behuviour 47, 185–193.CrossRefGoogle Scholar
Oldham, J. D., Buttery, P. J., Swan, H. & Lewis, D. (1977). Interactions between dietary carbohydrates and nitrogen in sheep. Journal of Agricultural Science, Cambridge 89, 467–479.CrossRefGoogle Scholar
Parker, D. S., Lomax, M. A., Seal, C. J. & Wilton, J. C. (1995). Metabolic implications of ammonia production in the ruminant. Proceedings of the Nutrition Society 54, 549–563.CrossRefGoogle ScholarPubMed
Parsons, A. J., Newman, J.A., Penning, P. D., Harvey, A. & Orr, R. J. (1994). Diet preferences of sheep: effects of recent diet, physiological state and species abundance. Journal of Animal Ecology 63, 465–478.CrossRefGoogle Scholar
Robinson, D. L. (1987). Estimation and use of variance components. Statistician 36, 3–14.CrossRefGoogle Scholar
Sinclair, L. A., Garnsworthy, P. C., Newbold, J. R. & Buttery, P. J. (1993). Effect of synchronising the rate of dietary energy and nitrogen release on rumen fermentation and microbial synthesis in sheep. Journal of Agricultural Science, Cambridge 120, 251–263.CrossRefGoogle Scholar
Sinclair, L. A., Gamsworthy, P. C., Newbold, J. R. & Buttery, P. J. (1995). Effects of synchronising the rate of dietary energy and nitrogen release in diets with a similar carbohydrate composition on rumen fermentation and microbial protein synthesis in sheep. Journal of Agricultural Science, Cambridge 124, 463–472.CrossRefGoogle Scholar
Visek, W. J. (1968). Some aspects of ammonia toxicity in animal cells. Journal of Dairy Science 51, 286–295.CrossRefGoogle ScholarPubMed