Abstract Improvements in ex situ storage of genetic and reproductive materials offer an alternative for endangered livestock breed conservation, but collections should be optimized cost-effectively to avoid duplication, and with reference to the sustainability of in situ breeds. We developed a multi-period chance-constrained optimization model to rationalize collections of endangered livestock breeds at risk of in situ extinction in Spain. The model configures collections by determining the least-cost optimal collection locations, timing and material quantities (semen doses). A decision variable defining an “acceptable level of risk” allows decision makers to specify tolerable levels of in situ breed endangerment when taking ex situ collection and storage decisions. Using data from 18 gene banks we demonstrate how collections can be rationalized, and derive cost curves relating marginal ex situ collection cost and accepted probability of in situ extinction covering the period 2018 to 2060. The modelling framework can be replicated in countries seeking to rationalize ex situ collections under limited conservation budgets and uncertain in situ extinction risks.

中文翻译：

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濒危牲畜品种保护的繁殖材料异地收集合理化

摘要 遗传和繁殖材料异地储存的改进为濒危牲畜品种保护提供了一种替代方案，但应以具有成本效益的方式优化收集，以避免重复，并参考就地品种的可持续性。我们开发了一个多期机会约束优化模型，以合理化收集西班牙面临就地灭绝风险的濒危牲畜品种。该模型通过确定成本最低的最佳采集位置、时间和材料数量（精液剂量）来配置采集。定义“可接受的风险水平”的决策变量允许决策者在做出非原生境采集和储存决策时指定可容忍的原生境品种濒危水平。使用来自 18 个基因库的数据，我们展示了如何合理化收集，