Abstract
Comparison of Different Lactation Models for Holstein Friesian Cows
This study carried out parameter estimations of the lactation curve of 371 lactation records that were obtained from 176 Holstein cattle that were bred in the period of 2004-2009 at the Kazova Vasfi Diren Agriculture Facilities using three different models (Wood, Cobby and Le Du and Wilmink). For this purpose, coefficient of determination (R2) and mean squared error (MSE) values were used to determine the best model. The highest coefficient of determination for the Wood model was found as 0.95 in the 5th lactation, while the mean squared error was found as 35.98. For the Cobby and Le Du model, the highest coefficient of determination value was found as 0.95 in the 4th and 5th lactations. For these periods, the mean squared error values were 57.76 and 35.90, respectively. For the Wilmink model, the highest coefficient of determination and the lowest mean squared error value were found as 0.35 and 37.29 respectively. In the study, it was determined that the Cobby and Le Du and Wood models with the minimum MSE and maximum R2 were the best models for estimating lactation curves for Holstein cattle at the Kazova Vasfi Diren Agriculture Facilities.
Keywords
Cobby and Le du, Holstein, Lactation curve, Wilmink, Wood
