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Interactions among tannins, supplementation and polyethylene glycol in goats given oak leaves: effects on digestion and food intake

Published online by Cambridge University Press:  02 September 2010

N. Silanikove
Affiliation:
Institute of Animal Science, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
N. Gilboa
Affiliation:
Institute of Animal Science, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
Z. Nitsan
Affiliation:
Institute of Animal Science, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
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Abstract

Effects were studied on food intake and diet apparent digestibility of giving to goats once daily a basal diet rich in tannin from inclusion of leaves of Quercus calliprinos either supplemented with a high carbohydrate or a high protein food. Also interactions with polyethylene glycol (PEG) were investigated. The results of the present work confirmed our presumption that the content of tannin in some Mediterranean browse is so high that it may negatively affect the utilization of protein in supplementary foods. Neutralizing the tannins with once-daily provision of PEG proved to be an effective means of preventing the negative effect. Providing 10 g/day PEG to goats given Quercus calliprinos leaves ad libitum and supplemented with 300 g/day concentrates containing 160 g crude protein per kg DM increased digestible crude protein intake by 50 g/day. When the concentrate food was given to goats, leaf dry-matter intake decreased significantly (from 664 to 565 g/day) and the goats lost weight rapidly. Therefore, supplementing tannin-rich leaves with concentrate food is recommended only if done in combination with PEG. High protein supplementation increased leaf (from 664 to 844 g/day) and digestible protein intakes (from 4·8 to 92·3 g/day) but a considerable portion of the protein supplementation was wasted due to interaction with tannins. PEG may allow economies in the use of such high-cost foods due to the greater efficiency of protein utilization (digestible crude protein intake increased from 92·3 to 122 g/day) of the supplementary food and to increased intake and protein utilization of the basal leaf diet (from 844 to 1023 g/day).

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1997

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References

Barry, T. N., Manley, R. T. and Duncan, S. T. 1986. The role of condensed tannins in the nutritional value of Lotus pedunculatus for sheep. 4. Site of carbohydrate and protein digestion as influenced by dietary reactive tannin concentrations. British Journal of Nutrition 55: 123137.Google Scholar
Egan, A. R. 1977. Nutritional status and intake regulation in sheep. VII. Relationships between the voluntary intake of herbage by sheep and the protein/energy ratio in the digestion products. Australian Journal of Agricultural Research 28: 907915.CrossRefGoogle Scholar
Forbes, J. M. 1995. Voluntary feed intake and diet selection farm animals. CAB International, Wallingford.Google Scholar
Kababya, D. 1994. Grazing behaviour and nutrition of goats in Mediterranean woodland. M.Sc. thesis, The Hebrew University ofJerusalem (Hebrew with English summary).Google Scholar
Meuret, M., Boza, J., Narjisse, H. and Nastis, A. 1990. Evaluation and utilization of rangelands feeds by goats. In Goat nutrition (ed. Morand-Fehr, P.), pp. 161170. PUDOC, Wageningen.Google Scholar
National Research Council. 1981. Nutrient requirement of goats, first edition. National Academy of Science Press, Washington, DC.Google Scholar
Provenza, F. D. 1995. Postingestive feedback as an elementary determinant of food selection and intake by ruminants. Journal of Range Management 48: 217.CrossRefGoogle Scholar
Robbins, C. T., Harley, T. A., Hagerman, A. E., Hjeljord, O., Baker, D. L., Schwartz, C. C. and Moutz, W. W. 1987. Role of tannins in defending plants against ruminants: reduction in protein availability. Ecology 68: 98107.CrossRefGoogle Scholar
Silanikove, N., Gilboa, N., Nir, I., Perevolotsky, A. and Nitsan, Z. 1996. Effect of a daily supplementation of polyethylene glycol on intake and digestion of tannin-containing leaves (Quercus calliprinos, Pistacia lentiscus Ceratonia siliqua) by goats. Journal of Agricultural and Chemistry 44: 199205.CrossRefGoogle Scholar
Silanikove, N., Nitsan, Z. and Perevolotsky, A. 1994. Effect of a daily supplementation of polyethylene glycol on intake and digestion of tannin-containing leaves (Ceratonia siliqua) by sheep. Journal of Agricultural and Food Chemistry 42: 28442847.Google Scholar
Statistical Analysis Systems Institute. 1982. SAS user's guide: statistics. Statistical Analysis Systems Institute Inc., Cary, NC.Google Scholar