We study the characteristics of contracts in cattle production in Ghana and explain variations in contract type using agency and transaction cost theory. In their study of pastoral groups, especially those in West Africa, anthropologists have distinguished between two categories of contracts in cattle production: cattle owner–herd manager contracts and herd manager–herdsman contracts. However, few studies have analysed the variations in contract type within each category. Using survey data from 342 cattle kraal owners, we explored the contract types under the two contract categories and analysed their drivers using crosstabulations. Contract types in each category can be explicit, with the reward given by the principal explicitly specified, or implicit and unspecified. Environmental uncertainty was associated with implicit contracts while for explicit contracts, kraal owners’ outside options or opportunity cost for monitoring was associated with fixed-wage contracts, subsidy-only contracts, and input contribution by kraal owners. The combination of moral hazard and measurement costs explained whether herdsmen were familial and not paid with milk or hired and paid with milk. Our findings provide further insights into the drivers of contract type.

中文翻译：

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牛群饲养和管理合同的性质和驱动因素：加纳案例

我们研究了加纳养牛业合同的特征，并使用代理和交易成本理论解释了合同类型的变化。在对牧民群体（尤其是在西非的牧民群体）的研究中，人类学家区分了牲畜生产中的两类合同：牲畜所有者－畜牧管理者合同和畜牧管理者－牧民合同。但是，很少有研究分析每个类别中合同类型的变化。我们使用来自342个牛头牛所有者的调查数据，探索了两个合同类别下的合同类型，并使用交叉表分析了其驱动因素。每个类别中的合同类型可以是显式的，显式指定的委托人给予的报酬，也可以是隐式和未指定的。环境的不确定性与隐性合同有关，而对于显性合同，人族所有者的外部选择权或监督机会成本与固定工资合同，仅补贴合同以及人族所有者的投入贡献有关。道德风险和衡量成本的结合说明了牧民是家族的，没有用牛奶付钱，还是雇用和用牛奶付钱。我们的发现为合同类型的推动因素提供了进一步的见解。