Development of High-value Traits of Dairy Cattle using Frailty Model

Abstract

In order to increase prot on dairy industry in Korea, reducing milk production costs can be a good way. In this study, we will develop high-value traits of dairy cattle using frailty model with data collected from Rural Development Administration in Korea. Survival analysis is used as there are censored observations. In particular, we use frailty model to consider the correlation between dairy cattle in the same farm. Since general variable selection criterions are not applied in the semi-parametric model like frailty model, we propose a criterion for variable selection. We evaluate the performance of the proposed criterion by simulation. And, we construct a model using the criterion and predict the economic life of dairy cattle. We can think that dairy cattle whose predicted economic life will be long have a high-value traits. Finally, we look at the increase rate of the economic life of dairy cattle when selecting dairy cattle with a high-value traits.