Abstract
A mechanistic model that predicts nutrient requirements and biological values of feeds for sheep and goats (Small Ruminant Nutrition System, SRNS) was developed based on the Cornell Net Carbohydrate and Protein System for sheep. The SRNS uses animal and environmental factors to predict metabolisable energy (ME) and protein requirements. This model has been subjected to an extensive evaluation. In particular, evaluation of the SRNS for sheep using published papers indicated good accuracy and precision in the prediction of organic matter and CP digestibility, while NDF digestibility was underpredicted. In addition, the SRNS accurately predicted daily ME intake (mean bias (MB) = 0.04 Mcal/d; root mean square error of prediction (RMSEP) = 0.24 Mcal/d; r2 = 0.99) of lactating goats and goat wethers. The SRNS also accurately predicted the ADG of lambs (n = 42; MB = 1 g/d; RMSEP = 37 g/d; r2= 0.84) and kids (n = 31; MB = −6.4 g/d; RMSEP = 32.5 g/d; r2= 0.85) and the gains and losses of shrunk body weight of adult sheep (MB = −5.8 g/d; RMSEP = 30 g/d; r2= 0.73) and the energy balance (n = 21; RMSEP = 0.20 Mcal/d; r2 = 0.87) of lactating goats and wethers. In conclusion, based on our accumulated evaluation of the SRNS with literature data, the SRNS accurately predicts nutrient supply and requirements of sheep and goats. Recent unpublished evaluations, however, suggested that the SRNS may underpredict ADG when compensatory growth occurs.
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References
AFRC (Agricultural and Food Research Council), 1993. Energy and Protein Requirements of Ruminants. Agricultural and Food Research Council. CAB International, Wallingford, UK, 159 pp.
ARC (Agricultural Research Council), 1980. The Nutrient Requirements of Ruminant Livestock. Agricultural Research Council. The Gresham Press, London, UK, 351 pp.
Cannas, A., 2002. Energy and protein requirements. In: G. Pulina (ed.). Dairy Sheep Feeding and Nutrition. Avenue Media, Bologna, Italy, pp.55–81.
Cannas, A., Atzori, A.S., Boe, F., and Teixeira, I.A.M.A., 2008. Energy and protein requirements of goats. In: A. Cannas and G. Pulina (eds.). Dairy Goats, Feeding and Nutrition. CAB International, Cambridge, MA, USA, pp.118–146.
Cannas, A., Linsky, A., Erasmus, L.J., Tedeschi, L.O., van Niekerk, W.A., and Coertze, R., 2009. Evaluation of performance predictions of the Small Ruminant Nutrition System model using growth and body composition data of South African Mutton Merino and Dorper. Journal of Animal Science 87 E-Suppl. 2:522.
Cannas, A., Tedeschi, L.O., Atzori, A.S., and Fox, D.G., 2006a. Prediction of energy requirements for growing sheep with the Cornell Net Carbohydrate and Protein System. In: J. Dijkstra (ed.). Nutrient Digestion and Utilization in Farm Animals. CABI Publishing, Cambridge, MA, USA, pp.99–113.
Cannas, A., Tedeschi, L.O., and Fox, D.G., 2006b. Small Ruminant Nutrition System: a computer model to develop feeding programs for sheep and goats. Journal of Animal Science, 84 (Suppl. 1), pp.376.
Cannas, A., Tedeschi, L.O., Atzori, A.S., and Fox, D.G., 2007a. Prediction of the growth rate of kids with the Small Ruminant Nutrition System. Anais da 44a Reunião Anual da Sociedade Brasileira de Zootecnia, pp.1–3. (CD-ROM).
Cannas, A., Tedeschi, L.O., and Fox, D.G., 2007b. Prediction of metabolizable energy intake and energy balance of goats with the Small Ruminant Nutrition System. In: Ortigues-Marty I. (ed.). Energy and protein metabolism and nutrition. EAAP publication No 124, Wageningen Academic Publishers, Wageningen, the Netherlands, pp.569–570.
Cannas, A., Tedeschi, L.O., Atzori, A.S., and Fox, D.G., 2007c. The Small Ruminant Nutrition System: development and evaluation of a goat submodel. Italian Journal of Animal Science 6 (Suppl. 1):609–611.
Cannas, A., Tedeschi, L.O., Fox, D.G., Pell, A.N., and Van Soest, P.J., 2004. A mechanistic model for predicting the nutrient requirements and feed biological values for sheep. Journal of Animal Science 82:149–169.
Cannas, A., and Van Soest P.J., 2000. Allometric models to predict rumen passage rate in domestic ruminants. In: J.P. McNamara, J. France and D.E. Beever (eds.). Modeling Nutrient Utilization in Farm Animals. CABI Publishing, Wallingford, Oxon, UK, pp.49–62.
CSIRO (Australian Commonwealth Scientifc and Industrial Research Organization), 1990. Feeding Standards for Australian Livestock. Ruminants. Commonwealth Scientifc and Industrial Research Organization, Melbourne, Australia, 266 pp.
CSIRO (Australian Commonwealth Scientifc and Industrial Research Organization), 2007. Nutrient Requirements of Domesticated Ruminants. Commonwealth Scientifc and Industrial Research Organization, Collingwood, Australia, 270 pp..
Fernandes, M.H.M.R., Resende, K.T., Tedeschi L.O., Fernandes, J.S., Silva, Jr., H.M., Carstens, G.E., Berchielli, T.T., Teixeira, I.A.M.A. and Akinaga, L., 2007. Energy and protein requirements for maintenance and growth of Boer crossbred kids. Journal of Animal Science 85:1014–1023.
Fox, D.G., Tedeschi, L.O., Tylutki, T.P., Russell, J.B., Van Amburgh, M.E., Chase, L.E., Pell, A.N., and Overton, T.R., 2004. The Cornell Net Carbohydrate and Protein System model for evaluating herd nutrition and nutrient excretion. Animal Feed Science and Technology 112:29–78.
Freer, M., Moore A.D., and Donnelly, J.R., 1997. GRAZPLAN: decision support systems for Australian grazing enterprises-II. The animal biology model for feed intake, production and reproduction and the GrazFeed DSS. Agricultural Systems 54:77–126.
Freetly, H.C., Nienaber, J.A. and Brown-Brandl, T., 2002. Relationships among heat production, body weight, and age in Finnsheep and Rambouillet ewes. Journal of Animal Science 80:825–832.
Galvani, D.B., Pires, C.C., Kozloski, G.V. and Wommer, T.P., 2008. Energy requirements of Texel crossbred lambs. Journal of Animal Science 86:3480–3490.
INRA (Institut National de la Recherche Agronomique), 1989. Ruminant nutrition. Recommended allowances and feed tables. John Libbey Eurotext, Montrouge, France, p. 389.
Ngwa, A.T., Dawson, L.J., Puchala, R., Detweiler, G., Merkel, R.C., Tovar-Luna, I., Shalu, T., Ferrell, C.L. and Goetsch, A.L., 2007. Urea space and body condition score to predict body composition of meat goats. Small Ruminant Research 73:27–36.
NRC (National Research Council), 1981. Nutritional Energetics of Domestic Animals and Glossary of Energy Terms. National Academy Press, Washington, DC, USA.
NRC (National Research Council), 1985. Nutrient Requirements of Sheep (6th ed.). National Academy Press, Washington, DC, USA, 99 pp.
NRC (National Research Council), 2000. Nutrient Requirements of Beef Cattle (updated 7th ed.). National Academy Press, Washington, DC, USA, 248 pp.
NRC (National Research Council), 2001. Nutrient Requirements of Dairy Cattle (7th ed.). National Academy Press, Washington, DC, USA, 381 pp.
NRC (National Research Council), 2007. Nutrient Requirements of Small Ruminants: Sheep, Goats, Cervids, and New World Camelids (6th ed.). National Academy Press, Washington, DC, USA 384 pp.
Pulina, G., Cannas, A., Serra, A., and Vallebella, R., 1992. Determinazione e stima del valore energetico di latte di capre di razza Sarda. Atti della Società Italiana di Scienze Veterinarie 45:1779–1781.
Sahlu, T., Goetsch, A.L., Luo, J., Nsahlai, I.V., Moore, J.E., Galyean, M.L., Owens, F.N., Ferrell, C.L. and Johnson, Z.B., 2004. Nutrient requirements of goats: developed equations, other considerations and future research to improve them. Small Ruminant Research 53:191–219.
Tedeschi, L.O., 2006. Assessment of the adequacy of mathematical models. Agricultural Systems 89:225–247.
Tedeschi, L.O., Cannas, A. and Fox, D.G., 2010. A nutrition mathematical model to account for dietary supply and requirements of energy and nutrients for domesticated small ruminants: the development and evaluation of the Small Ruminant Nutrition System. Small Ruminant Research, in press: doi.org/10.1016/j. smallrumres.2009.12.041.
Tedeschi, L.O., Fox, D.G., and Guiroy, P.J., 2004. A decision support system to improve individual cattle management. 1. A mechanistic, dynamic model for animal growth. Agricultural Systems 79:171–204.
Tedeschi, L.O., Fox, D.G., Sainz, R.D., Barioni, L.G., Medeiros, S.R. and Boin, C., 2005. Using mathematical models in ruminant nutrition. Scientia Agricola 62:76–91.
Tedeschi, L.O., Seo, S., Fox, D.G. and Ruiz, R., 2006. Accounting for energy and protein reserve changes in predicting diet-allowable milk production in cattle. Journal of Dairy Science 89:4795–4807.
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Cannas, A., Tedeschi, L.O., Atzori, A.S., Fox, D.G. (2011). The development and evaluation of the Small Ruminant Nutrition System. In: Sauvant, D., Van Milgen, J., Faverdin, P., Friggens, N. (eds) Modelling nutrient digestion and utilisation in farm animals. Wageningen Academic Publishers, Wageningen. https://doi.org/10.3920/978-90-8686-712-7_29
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DOI: https://doi.org/10.3920/978-90-8686-712-7_29
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