Estimation of body composition in tropical sheep raised under seasonal feed supply conditions: Prediction models
Prediction models were developed from isotope dilution space (D2O) and live animal measurements (heart girth, height at withers, body length and tail volume measurements) to estimate chemical body components of indigenous tropical fat-tailed sheep breeds in vivo. A STEPWISE multiple regression proce...
| Main Authors: | , , , |
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| Format: | Conference Paper |
| Language: | Inglés |
| Published: |
Bunda College of Agriculture
2001
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| Online Access: | https://hdl.handle.net/10568/4195 |
| _version_ | 1855522938947633152 |
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| author | Negussie, E. Rottmann, O.J. Pirchner, F. Rege, J.E.O. |
| author_browse | Negussie, E. Pirchner, F. Rege, J.E.O. Rottmann, O.J. |
| author_facet | Negussie, E. Rottmann, O.J. Pirchner, F. Rege, J.E.O. |
| author_sort | Negussie, E. |
| collection | Repository of Agricultural Research Outputs (CGSpace) |
| description | Prediction models were developed from isotope dilution space (D2O) and live animal measurements (heart girth, height at withers, body length and tail volume measurements) to estimate chemical body components of indigenous tropical fat-tailed sheep breeds in vivo. A STEPWISE multiple regression procedure of SAS was used to assess the predictive power of combinations of variables and models which minimise the predicted residual sum of squares. With regard to the accuracy and robustness of prediction, models containing body weight as the only predictor variable resulted in less accurate estimates of body components, especially that of body fat and energy contents. However, the use of isotope dilution space (as an index of Total Body Water) along with body weight measurements showed significant improvements in R² and accuracy of prediction equations. Testing the predictive ability of models containing live animal measures only, the result obtained showed that, despite a small reduction in accuracy, indices of live animal measures gave comparable estimation of body components with models containing isotope dilution space. Therefore, considering the cost of D2O and its applicability in the field, indications are that the use of models containing indices of live animal measurements only (in various combinations) is promising for field applications, to provide longitudinal measures of change in body composition of tropical fat-tailed sheep. |
| format | Conference Paper |
| id | CGSpace4195 |
| institution | CGIAR Consortium |
| language | Inglés |
| publishDate | 2001 |
| publishDateRange | 2001 |
| publishDateSort | 2001 |
| publisher | Bunda College of Agriculture |
| publisherStr | Bunda College of Agriculture |
| record_format | dspace |
| spelling | CGSpace41952025-11-04T16:58:26Z Estimation of body composition in tropical sheep raised under seasonal feed supply conditions: Prediction models Negussie, E. Rottmann, O.J. Pirchner, F. Rege, J.E.O. Prediction models were developed from isotope dilution space (D2O) and live animal measurements (heart girth, height at withers, body length and tail volume measurements) to estimate chemical body components of indigenous tropical fat-tailed sheep breeds in vivo. A STEPWISE multiple regression procedure of SAS was used to assess the predictive power of combinations of variables and models which minimise the predicted residual sum of squares. With regard to the accuracy and robustness of prediction, models containing body weight as the only predictor variable resulted in less accurate estimates of body components, especially that of body fat and energy contents. However, the use of isotope dilution space (as an index of Total Body Water) along with body weight measurements showed significant improvements in R² and accuracy of prediction equations. Testing the predictive ability of models containing live animal measures only, the result obtained showed that, despite a small reduction in accuracy, indices of live animal measures gave comparable estimation of body components with models containing isotope dilution space. Therefore, considering the cost of D2O and its applicability in the field, indications are that the use of models containing indices of live animal measurements only (in various combinations) is promising for field applications, to provide longitudinal measures of change in body composition of tropical fat-tailed sheep. 2001 2011-07-15T13:55:26Z 2011-07-15T13:55:26Z Conference Paper https://hdl.handle.net/10568/4195 en Open Access application/pdf Bunda College of Agriculture Negussie, E., Rottmann, O.J., Pirchner, F. and Rege, J.E.O. 2001. Estimation of body composition in tropical sheep raised under seasonal feed supply conditions: Prediction models. IN: Banda, J.W., Chagunda, M.G.G., Kamwanja, L.A., Phoya, R.K.D and Safalaoh, A.C.L. (eds.). 2001. Sustainable animal agriculture and crisis mitigation in livestock-dependent systems in southern Africa: Proceedings of the regional conference held at Malawi Institute of Management, 30 October to 1 November 2000. Lilongwe, Malawi: Bunda College of Agriculture. |
| spellingShingle | Negussie, E. Rottmann, O.J. Pirchner, F. Rege, J.E.O. Estimation of body composition in tropical sheep raised under seasonal feed supply conditions: Prediction models |
| title | Estimation of body composition in tropical sheep raised under seasonal feed supply conditions: Prediction models |
| title_full | Estimation of body composition in tropical sheep raised under seasonal feed supply conditions: Prediction models |
| title_fullStr | Estimation of body composition in tropical sheep raised under seasonal feed supply conditions: Prediction models |
| title_full_unstemmed | Estimation of body composition in tropical sheep raised under seasonal feed supply conditions: Prediction models |
| title_short | Estimation of body composition in tropical sheep raised under seasonal feed supply conditions: Prediction models |
| title_sort | estimation of body composition in tropical sheep raised under seasonal feed supply conditions prediction models |
| url | https://hdl.handle.net/10568/4195 |
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