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Diet selection of sheep: effects of adding urea to foods with different protein contents

Published online by Cambridge University Press:  18 August 2016

S. M. James ,
I. Kyriazakis  and
G. C. Emmans
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Abstract

Two experiments were conducted in which growing sheep were given choices between foods differing in their contents of urea. The crude protein (CP) contents of both of the foods of the pair were also varied. The hypothesis tested was that the diets selected would be those that met the effective rumen degradable protein (eRDP) requirements of the animals and would avoid excess consumption of eRDP. Three basal foods, differing in CP were formulated. D was designed to be deficient in CP with 80 g CP and 58 g eRDP per kg DM; H was calculated to be adequate with 159 g CP and 114 g eRDP per kg DM; P had excess with 210 g CP and 148 g eRDP per kg DM. Other foods were made by adding 12·5 or 25 g urea per kg fresh matter to each of the three basal foods to make a further six foods. In both experiments Texel ✕ Greyface female sheep were used. In experiment 1, 34 sheep weighing 37·2 (s.d. 1·85) kg were randomly allocated to one of six groups and each group was offered a choice between a pair of foods. Groups 1 to 3 were offered pairs in the D series (D v. D + 12·5 g urea per kg (no. = 6), D v. D + 25 g urea per kg (no. = 6) and D + 12·5 g urea per kg v. D + 25 g urea per kg (no. = 5)). Groups 4 to 6 were offered the same pairs of foods but with H instead of D. In experiment 2, 96 sheep weighing 29·8 (s.d. 3·37) kg were randomly allocated to one of 12 groups. Groups 1 to 6 (no. = 6) were allocated a single food (D, D + 25 g, H, H + 25 g, P or P + 25 g urea per kg) throughout the experiment. Groups 7 to 12 were given a choice (no. = 10) between two foods. One food of the pair was the basal D, H or P. The other food was the same basal food supplemented with either 12·5 or 25 g urea per kg. On the single foods adding urea to D resulted in an increase in food intake and live-weight gain suggesting that D was deficient in eRDP. Adding urea to either H or P had no beneficial effects on intake or live-weight gain. This suggests that both contained sufficient eRDP in relation to energy. Across all choice treatments in both experiments there was a highly significant preference (P < 0·01) for the food with the higher urea content. In experiment 1 0·62 (s.e. 0·04) of the diet selected was the food with the higher urea content. In experiment 2 the figure was 0·64 (s.e.0·03). The general preference for the food with the higher urea content was unaffected by the CP contents of the foods used. The results do not support the hypothesis that sheep will avoid excess eRDP when given a choice and suggest that eRDP may not be a relevant dimension in diet selection in the conditions of these experiments.

Keywords

food intakefood preferencesprotein intakesheepurea.
Type
Ruminant nutrition, behaviour and production
Information
Animal Science , Volume 73 , Issue 1 , August 2001 , pp. 183 - 195
Copyright
Copyright © British Society of Animal Science 2001

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References

Agricultural and Food Research Council. 1993. Energy and protein requirements of ruminants. An advisory manual prepared by the AFRC Technical Committee on Responses to Nutrients. CAB International, Wallingford.Google Scholar
Agricultural Research Council. 1980. The nutrient requirements of ruminant livestock. Commonwealth Agricultural Bureaux, Farnham Royal.Google Scholar
Arsenos, G. 2000. The role of learning in the selection for dietary protein by sheep. Ph. D. thesis, University of Edinburgh.Google Scholar
Bornett, H. L. I., Morgan, C. A., Lawrence, A. B. and Mann, J. 2000. The flexibility of feeding patterns in individually housed pigs. Animal Science 70: 457–469.CrossRefGoogle Scholar
Bradford, M. M. V. and Gous, R. M. 1991. The response of growing pigs to a choice of diets differing in protein content. Animal Production 52: 185–192.Google Scholar
Campion, D. P. and Leek, B. F. 1997. Investigation of ‘fibre appetite’ in sheep fed a ‘long fibre-free’ diet. Applied Animal Behavioural Science 52: 79–86.Google Scholar
Chamberlain, D. G. and Choung, J. J. 1995. The importance of rate of ruminal fermentation of energy source in diets for dairy cows. In Recent advances in animal nutrition (ed. Garnsworthy, P. C. and Cole, D. J. A.), pp. 3–27. Nottingham University Press, Nottingham.Google Scholar
Cooper, S.D. B., Kyriazakis, I. and Nolan, J. V. 1995. Diet selection in sheep — the role of the rumen environment in the selection of a diet from 2 feeds that differ in their energy density. British Journal of Nutrition 74: 35–54.Google Scholar
Cooper, S.D.B., Kyriazakis, I. and Oldham, J. D. 1994. The effect of late pregnancy on the diet selection made by ewes. Livestock Production Science 40: 263–275.Google Scholar
Cropper, M. R. 1987. Growth and development of sheep in relation to feeding strategy. Thesis, University of Edinburgh.Google Scholar
Dulphy, J. P., Jamot, J., Chenost, M., Besle, J. M. and Chiofalo, V. 1992. The influence of urea treatment on the intake of wheat straw in sheep. Annales de Zootechnie 41: 169–185.Google Scholar
Egan, J. K. and Doyle, P. T. 1985. Effect of intraruminal infusion of urea on the response in voluntary food intake by sheep. Australian Journal of Agricultural Research 36: 483–495.Google Scholar
Emmans, G. C. 1991. Diet selection by animals: theory and experimental design. Proceedings of the Nutrition Society 50: 59–64.Google Scholar
Forbes, J. M. and Shariatmadari, F. 1994. Diet selection for protein by poultry. World’s Poultry Science Journal 50: 7–24.Google Scholar
Friggens, N. C., Shanks, M., Kyriazakis, I., Oldham, J. D. and McClelland, T. H. 1997. The growth and development of nine European sheep breeds. 1. British breeds: Scottish Blackface, Welsh Mountain and Shetland. Animal Science 65: 409–426.CrossRefGoogle Scholar
Gorgulu, M., Kutlu, H. R., Demir, E., Ozturkcan, O. and Forbes, J. M. 1996. Nutritional consequences among ingredients of free-choice feeding Awassi lambs. Small Ruminant Research 20: 23–29.Google Scholar
Gower, A. J. and Lamberty, Y. 1993. The aged mouse as a model of cognitive decline with special emphasis on studies in NMRI mice. Behavioural Brain Research 57: 163–173.Google Scholar
Haaland, G. L., Tyrrell, H. F., Moe, P. W. and Wheeler, W. E. 1982. Effects of crude protein level and limestone buffer in diets fed at two levels of intake on rumen pH, ammonia nitrogen, buffering capacity and volatile fatty acid concentration of cattle. Journal of Animal Science 55: 943–950.Google Scholar
Hou, X. Z. 1991. Diet selection in sheep. Ph.D. thesis, University of Edinburgh.Google Scholar
James, S. M. and Kyriazakis, I. 1999. The effect of consumption of foods that differ in energy density and/or sodium bicarbonate supplementation on subsequent diet selection in sheep. Proceedings of the British Society of Animal Science, 1999, p. 114.Google Scholar
Kahn, L. P. 1996. Dynamics of allantoin metabolism in sheep. Differences between Merino selection lines in microbial yield from the rumen and utilisation of protein for wool growth. Ph. D. thesis, University of New England, Armidale.Google Scholar
Kanjanapruthipong, J. and Leng, R. A. 1998. The effects of dietary urea on microbial populations in the rumen of sheep. Asian-Australasian Journal of Animal Sciences 11: 661–672.Google Scholar
Kenward, M. G. 1987. A method of comparing profiles of repeated measurements. Applied Statistics 36: 296–308.Google Scholar
Kyriazakis, I. 1997. The nutritional choices of farm animals: to eat or what to eat? In Animal choices (ed. Forbes, J. M., Lawrence, T. L. J., Rodway, R. G. and Varley, M. A.), British Society of Animal Science occasional publication no. 20, pp. 55–65.Google Scholar
Kyriazakis, I. and Emmans, G. C. 1991. Diet selection in pigs: dietary choices made by growing pigs following a period of underfeeding with protein. Animal Production 52: 337–346.Google Scholar
Kyriazakis, I., Emmans, G. C. and Whittemore, C. T. 1990. Diet selection in pigs: choices made by growing pigs given foods of different protein concentrations. Animal Production 51: 189–199.Google Scholar
Kyriazakis, I. and Oldham, J. D. 1993. Diet selection in sheep: the ability of growing lambs to select a diet that meets their crude protein (nitrogen ✕ 6·25) requirements. British Journal of Nutrition 69: 617–629.Google Scholar
Kyriazakis, I., Tolkamp, B. J. and Emmans, G. C. 1999. Diet selection and animal state: an integrative framework. Proceedings of the Nutrition Society 58: 765–772.Google Scholar
Langlands, J. P. 1969. Studies on the nutritive value of the diet selected by grazing sheep. IV. Variation in the diet selected by sheep differing in age, breed, sex, strain and previous history. Animal Production 11: 369–379.Google Scholar
Lawes Agricultural Trust. 1993. GENSTAT 5 release 3·2 reference manual, second edition. Clarendon Press, Oxford.Google Scholar
Lawson, R. E., Redfern, E. J. and Forbes, J. M. 2000. Choices by lactating cows between concentrates high or low in digestible undegraded protein. Animal Science 70: 515–525.Google Scholar
Leshner, A. I., Siegel, H. I. and Collier, G. 1972. Dietary self-selection by pregnant and lactating rats. Physiology and Behavior 8: 151–154.Google Scholar
Lobley, G. E., Connell, A., Lomax, M. A., Brown, D. S., Milne, E., Calder, A. G. and Farningham, D. A. H. 1995. Hepatic detoxification of ammonia in the ovine liver: possible consequences for amino acid catabolism. British Journal of Nutrition 73: 667–685.Google Scholar
Manyuchi, B., Mikayiri, S. and Smith, T. 1994. Effects of treatment or supplementing maize stover with urea on its utilisation as feed for sheep and cattle. Animal Feed Science and Technology 49: 11–12.Google Scholar
Milton, C. T., Brandt, R. T. and Titgemeyer, E. C. 1997. Urea in dry-rolled corn diets: finishing steer performance, nutrient digestion, and microbial protein production. Journal of Animal Science 75: 1415–1424.Google Scholar
Ministry of Agriculture, Fisheries and Food. 1990. UK tables of nutritive value and chemical composition of feedingstuffs (ed. Givens, D. I. and Moss, A. R.). Rowett Research Services Ltd, Aberdeen.Google Scholar
Ministry of Agriculture, Fisheries and Food. 1993. The determination of neutral detergent (plus amylase) fibre (NDF) of feeding stuffs, appendix III. In Prediction of the energy values of compound feeding stuffs for farm animal: summary of recommendations of a working party sponsored by the Ministry of Agriculture, Fisheries and Food. MAFF publications, London.Google Scholar
Minitab Inc. 1996. Minitab for Windows, release 11·1. Minitab Inc., State College, 3081 Enterprise Drive, PA 16801-3008, USA.Google Scholar
Musten, B., Peace, D. and Anderson, G. H. 1974. Food intake regulation in the weanling rat: self-selection of protein and energy. Journal of Nutrition 104: 563–572.Google Scholar
Newbold, J. R. 1987. Nutrient requirements of intensively reared beef cattle. In Recent advances in animal nutrition (ed. Haresign, W. and Cole, D.J. A.), pp. 143–171. Butterworths, London.Google Scholar
Newman, J. A., Penning, P. D., Parsons, A. J., Harvey, A. and Orr, R. J. 1994. Fasting affects intake behaviour and diet preference of grazing sheep. Animal Behaviour 47: 185–193.Google Scholar
Nomani, M. 1973. Effect of dietary source and level of protein on voluntary dry matter intake and the metabolism of nitrogen in growing ruminants. Ph.D. thesis, Rutgers University, State University of New Jersey.Google Scholar
Ørskov, E. R., Fraser, C. and McDonald, I. 1972. Digestion of concentrates in sheep. 4. The effects of urea on digestion, nitrogen retention and growth in young lambs. British Journal of Nutrition 27: 491–501.Google Scholar
Owens, F. N., Secrist, D. S., Hill, W. J. and Gill, D. R. 1998. Acidosis in cattle: a review. Journal of Animal Science 76: 275–286.Google Scholar
Parker, D. S., Lomax, C. J., Seal, C. J. and Wilton, J. C. 1995. Metabolic implications of ammonia production in the ruminant. Proceedings of the Nutrition Society 54: 549–563.Google Scholar
Parsons, A. J., Newman, J. A., Penning, P. D., Harvey, A. and Orr, R. J. 1994. Diet preference of sheep: effects of recent diet, physiological-state and species abundance. Journal of Animal Ecology 63: 465–478.Google Scholar
Phy, T. S. and Provenza, F. D. 1998. Sheep fed grain prefer foods and solutions that attenuate acidosis. Journal of Animal Science 76: 954–960.Google Scholar
Poos, M. I., Bull, L. S. and Hemken, R. W. 1979. Supplementation of diets with positive and negative urea fermentation potential using urea or soybean meal. Journal of Animal Science 49: 1417–1426.Google Scholar
Provenza, F. D. 1996. Acquired aversions as the basis for varied diets of ruminants foraging on rangelands. Journal of Animal Science 74: 2010–2020.Google Scholar
Provenza, F. D., Scott, C. B., Phy, T. S. and Lynch, J. J. 1996. Preference of sheep for foods varying in flavors and nutrients. Journal of Animal Science 74: 2355–2361.Google Scholar
Qi, K., Owens, F. N. and Lu, C. D. 1994. Effects of sulphur deficiency on performance of fibre-producing sheep and goats – a review. Small Ruminant Research 14: 115–126.Google Scholar
Rose, S. P. and Kyriazakis, I. 1991. Diet selection of pigs and poultry. Proceedings of the Nutrition Society 50: 87–98.Google Scholar
Shain, D. H., Stock, R. A., Klopfenstein, T. J. and Herold, D. W. 1998. Effects of degradable intake protein level on finishing cattle performance and ruminal metabolism. Journal of Animal Science 76: 242–248.Google Scholar
Tolkamp, B. J., Dewhurst, R. J., Friggens, N. C., Kyriazakis, I., Veerkamp, R. F. and Oldham, J. D. 1998a. Diet choice by dairy cows. 1. Selection of feed protein content during the first half of lactation. Journal of Dairy Science 81: 2657–2669.Google Scholar
Tolkamp, B. J., Kyriazakis, I., Oldham, J. D., Lewis, M., Dewhurst, R. J. and Newbold, J. R. 1998b. Diet choice by dairy cows. II. Selection for metabolisable protein or for rumen degradable protein? Journal of Dairy Science 81: 2670–2680.Google Scholar
Van Soest, P. J. 1994. Nutritional ecology of the ruminant, second edition. Cornell University Press, Ithaca, NY.Google Scholar
Villalba, J. J. and Provenza, F. D. 1997. Preference for flavoured foods by lambs conditioned with intraruminal administration of nitrogen. British Journal of Nutrition 78: 545–561.Google Scholar