Renkema J A, Stelwagen J
Tijdschr Diergeneeskd. 1977 Jun 1;102(11):670-6.
A model, initially based on the work of Zeddies (10), is presented , by which the economic aspects of the replacement problem may be studied. First, the principle underlying the replacement decision is discussed. Then, the data to be included in the model are determined. This mainly concerns the elements associated with age, such as milk production, the value of newborn calves, the slaughter of the cows, the feed cost and the cost of a pregnant heifer just before calving. The age-associated probability of culling is also included in the model. A number of questions regarding the economic importance of the duration of herd life have been studied using this model. In the third paper, the results of this application of the model will be presented.
本文提出了一个最初基于泽迪斯（10）研究成果的模型，通过该模型可以研究更换问题的经济方面。首先，讨论了更换决策所依据的原则。然后，确定模型中应包含的数据。这主要涉及与年龄相关的因素，如产奶量、新生犊牛的价值、奶牛的屠宰、饲料成本以及即将产犊的怀孕小母牛的成本。模型中还包括与年龄相关的淘汰概率。使用该模型研究了一些关于畜群寿命持续时间的经济重要性的问题。在第三篇论文中，将展示该模型应用的结果。
