Asian-Australasian Journal of Animal Sciences
- Volume 8 Issue 4
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- Pages.365-368
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- 1995
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- 1011-2367(pISSN)
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- 1976-5517(eISSN)
DOI QR Code
ALTERATION MODELS TO PREDICT LACTATION CURVES FOR DAIRY COWS
- Sudarwati, H. (Department of Animal Husbandry, University of Brawijaya) ;
- Djoharjani, T. (Department of Animal Husbandry, University of Brawijaya) ;
- Ibrahim, M.N.M. (Department of Animal Production Systems, Agricultural Universtiy)
- Received : 1994.07.19
- Accepted : 1995.04.11
- Published : 1995.08.01
Abstract
Lactation curves of dairy cows were generated using three models, namely; incomplete gamma function (model 1), polynomial inverse function (model 2) and non-linear regression (model 3). Secondary milk yield data of 27 cows which had completed 6 lactations were used in this study. Milk yield records (once a week) throughout the lactation and from the first three months of lactation were fitted to the models. Estimation of total milk yield by model 3 using the data once a week throughout the lactation resulted in smaller % bias and standard error than those generated from model 1 and 2. But, model 2 was more accurate in predicting the 305-day milk yield equivalent closer to actual yields with smaller bias % and error using partial records up to 3 months. Also, model 2 was able to estimate the time to reach peak yield close to the actual data using partial records and model 2 could be used as a tool to advise farmers on appropriate feeding and management practices to be adopted.