A Decision Tree Model to Determine Some Environmental Factors Affecting 305-Day Milk Yield in Simmental Cows

Abstract

In this study, some environmental factors thought to be effective on 305-day milk yield in Simmental cows, were examined according to the decision tree method with regression tree algorithm. For this purpose, the effect levels of calving interval, somatic cell count, calving age, and parity variables on the 305-day milk yield of 148 Simental cows were determined. As a result of the decision tree application, the factors affecting 305-day milk yield were found as parity, calving age, somatic cell count, and calving interval, in order of importance. In addition, it was determined that the 305-day milk yield of the cows with the calving age above 5 was high, and the cows with the somatic cell count greater than 104.500 were found to be the lowest. There is a need to use the decision tree approach in order to examine the effects of other environmental factors that are thought to be effective on milk yield or other economic characteristics in dairy farming and to provide appropriate conditions by correcting the relevant factors accordingly.