Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-05T06:55:46.574Z Has data issue: false hasContentIssue false

Influences of cold exposure on digestion of organic matter, rates of passage of digesta in the gastrointestinal tract, and feeding and rumination behaviour in sheep given four forage diets in the chopped, or ground and pelleted form

Published online by Cambridge University Press:  07 March 2008

P. M. Kennedy
Affiliation:
Department of Animal Science, The University of Alberta, Edmonton, Alberta T6G 2P5, Canada
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. Sixteen sheep, each fitted with cannulas in the rumen and proximal duodenum, were given four diets in the chopped or ground and pelleted form, at fixed intakes at intervals of 2 h. The sheep were closely shorn and exposed to temperatures of 22–25° or 1–4° for four periods of 45 d. Flow of duodenal digesta by reference to the markers CoEDTA and 103Ru-phenanthroline, chewing behaviour and particle size of rumen and duodenal digesta were measured.

2. Apparent digestibility of organic matter (OM) in the gastrointestinal tract was depressed (P < 0.05) by grinding and pelleting the diet, and by exposure of sheep to cold ambient temperatures. This was attributable to depression (P < 0.01) by 0.1 of OM digestion in the reticulo-rumen. No effects on intestinal digestion of OM were observed.

3. Cold ambient temperatures did not affect the content, but increased the rate of digestion for pelleted diets but not for chopped diets, of potentially-degradable cell-wall constituents of ground dietary material incubated in nylon-bags in the rumen.

4. Retention times of markers of the particulate and liquid phases of rumen digesta were not significantly (P < 0.05) affected by ambient temperature, despite significant (P < 0.001) increases in the rate of contraction of the reticulum. Retention time of 103Ru-phenanthroline in the intestines was not affected by cold exposure.

5. Cold exposure was associated with depression (P < 0.05) of volatile fatty acids concentration in the rumen and elevated (P < 0.05) pH. Molar proportions of acetic and isovaleric acid were reduced (P < 0.01), accompanied by increased (P < 0.001) proportions of propionic acid during cold exposure.

6. Cold exposure and pelleting of the diets were both associated with reduction in digesta particle size in the rumen. Duodenal particle size was not affected by cold exposure. Pelleting of the diet markedly reduced (P < 0.001) duration of chewing and number of chews/d during eating and rumination. Cold exposure of sheep resulted in a faster (P < 0.01) rate of eating of the diets.

7. When allowed to express their voluntary feed consumption during a 10 d period, intakes of chopped diets were increased by 0.13 (P < 0.01) by cold exposure, in contrast to lack of significant change in sheep given pellets.

8. The results did not support the hypothesis that the effect of cold exposure on digestion was dependent on the physical form of the diet given at fixed intake, but did indicate that increased voluntary feed consumption was a result of increased clearance of digesta from the rumen throdgh decreased rumen particle size and increased reticulum motility.

Type
Papers on General Nutrition
Copyright
Copyright © The Nutrition Society 1985

References

REFERENCES

Bae, D. H., Welch, J. G. & Smith, A. M. (1979). Journal of Animal Science 49, 12911299.CrossRefGoogle Scholar
Beever, D. E. & Thomson, D. J. (1982). Grass and Forage Science 36, 211219.CrossRefGoogle Scholar
Campling, R. C. (1970). In Physiology of Digestion and Metabolism in the Ruminant, pp. 226235 [Phillipson, A. T., editor]. Newcastle upon Tyne: Oriel Press.Google Scholar
Chai, K., Kennedy, P. M., Milligan, L. P., & Mathison, G. W. (1985). Canadian Journal of Animal Science 65, (In the Press.)CrossRefGoogle Scholar
Christopherson, R. J. & Kennedy, P. M. (1983). Canadian Journal of Animal Science 63, 477496.CrossRefGoogle Scholar
Dixon, R. M., Kennelly, J. J. & Milligan, L. P. (1983). British journal of Nutrition 49, 463473.CrossRefGoogle Scholar
Dixon, R. M. & Milligan, L. P. (1985). British Journal of Nutrition 53 (In the Press.)CrossRefGoogle Scholar
El-Shazly, K. (1952). Biochemical Journal 51, 647653.CrossRefGoogle Scholar
Faichney, G. J. (1975). InDigestion and Metabolism in the Ruminant, pp. 277291 [McDonald, I. W. and Warner, A. C. I., editors]. Armidale: University of New England Publishing Unit.Google Scholar
Freer, M., Campling, R. C. & Balch, C. C. (1962). British Journal of Nutrition 16, 279295.CrossRefGoogle Scholar
Gonyou, H. W., Christopherson, R. J. & Young, B. A. (1979). Applied Animal Ethology 5, 113124.CrossRefGoogle Scholar
Kennedy, P. M. (1983). Proceedings of the New Zealand Society of Animal Production 43, 123125.Google Scholar
Kennedy, P. M., Christopherson, R. J. & Milligan, L. P. (1976). British Journal of Nutrition 36, 231242.CrossRefGoogle Scholar
Kennedy, P. M., Christopherson, R. J. & Miiligan, L. P. (1982). British Journal of Nutrition 47, 521535.CrossRefGoogle Scholar
Kennedy, P. M., Christopherson, R. J. & Milligan, L. P. (1985). VI International Symposium on Ruminant Physiology, (In the Press.)Google Scholar
Kennedy, P. M. & Milligan, L. P. (1978). British Journal of Nutrition 39, 105117.CrossRefGoogle Scholar
Leek, B. F. & Harding, R. H. (1975). In Digestion and Metabolism in the Ruminant, pp. 60 76. [McDonald, I. W. and Warner, A. C. I., editors]. Armidale: University of New England Publishing Unit.Google Scholar
McDonald, I. (1981). Journal of Agricultural Science, Cambridge 96, 251252.CrossRefGoogle Scholar
Moseley, G. & Jones, J. R. (1979). British Journal of Nutrition 42, 139147.CrossRefGoogle Scholar
Shipley, R. A. & Clark, R. E. (1972). Tracer Methods for In Vivo Kinetics. New york and London: Academic Press.Google Scholar
Sokal, R. R. & Rohlf, F. J. (1969). Biometry. San Francisco: W. H. Freeman & Co.Google Scholar
Tan, T., Weston, R. H. & Hogan, J. P. (1971). International Journal of Applied Radiation and Isotopes 22, 301308.CrossRefGoogle Scholar
Thomson, D. J. & Beever, D. E. (1980). In Digestive Physiology and Metabolism in Ruminants, pp. 291308. Ruckebusch, Y. and Thivend, P., editors]. Lancaster: MTP Press.CrossRefGoogle Scholar
Uden, P., Colucci, P. & Van Soest, P. J. (1980). Journal of the Science of Food and Agriculture 31, 625632.CrossRefGoogle Scholar
Van Soest, P. J. (1982). Nutritional Ecology of the Ruminant. Corvallis: O & B Books Inc.Google Scholar
Waldo, D. R., Smith, L. N., Cox, E. L., Weinland, B. T. & Lucas, H. L. (1971). Journal of Dairy Science 54, 14651469.CrossRefGoogle Scholar
Welch, J. G., Palmer, R. H. & Gilman, B. E. (1981). Journal of Animal Science 55 suppl 1, 474.Google Scholar
Weston, R. H. (1983). Proceedings of the Nutrition Society of Australia 8, 181184.Google Scholar
Westra, R. & Christopherson, R. J. (1976). Canadian Journal of Animal Science 56, 699708.CrossRefGoogle Scholar
Wilkins, R. J., Lonsdale, C. R., Tetlow, R. M. & Forrest, T. J. (1972). Animal Production 14, 177188.Google Scholar