Evaluation of goodness of fit of two empirical models applied to East Friesian sheep lactations
Abstract
Sheep milk production is an important economic activity in some countries of Europe and Asia. However, in the last decades there has been an incipient development of this industry in some Latin American countries. The aim of the current work is to evaluate the goodness of fit of two empirical models to describe lactations curves of East Friesian sheep in a temperate region in Mexico. A total of 38 lactations, comprising 254 test-day records (TDR) of East Friesian sheep from a commercial dairy farm located in the Jilotepec, Estado de Mexico, Mexico, were analyzed to investigate the goodness of fit of two empirical lactation models (Wood and Wilmink models). The goodness of fit of empirical models was evaluated using the mean square of prediction error (MSPE), root-mean-square prediction error (RMSPE), Akaike information criterion (AIC) and Bayesian information criterion (BIC). According with the used criteria the Wood model depicts better fitting of analyzed lactation curves with lower values of MSPE (0.013 vs. 0.014), RMSPE (0.101 vs 0.104), AIC (-5.67 vs. -5.03) and BIC (-6.11 vs. -4.84) in comparison with the Wilmink model.
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References
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