Department of Economics, Swedish University of Agricultural Sciences, PO Box 7013, SE-75007 Uppsala, Sweden; Department of Agricultural Economics, Extension & Rural Development, University of Pretoria, Private Bag X20, Pretoria, South Africa; Department of Agricultural Economics, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa.
Department of Clinical Sciences, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden; Växa Sverige, SE-104 25 Stockholm, Sweden.
J Dairy Sci. 2023 May;106(5):3509-3524. doi: 10.3168/jds.2022-22808. Epub 2023 Apr 5.
A dairy farmer's decision to cull or keep dairy cows is likely a complex decision based on animal health and farm management practices. The present paper investigated the relationship between cow longevity and animal health, and between longevity and farm investments, while controlling for farm-specific characteristics and animal management practices, by using Swedish dairy farm and production data for the period 2009 to 2018. We used the ordinary least square and unconditional quantile regression model to perform mean-based and heterogeneous-based analysis, respectively. Findings from the study indicate that, on average, animal health has a negative but insignificant effect on dairy herd longevity. This implies that culling is predominantly done for other reasons than poor health status. Investment in farm infrastructure has a positive and significant effect on dairy herd longevity. The investment in farm infrastructure creates room for new or superior recruitment heifers without the need to cull existing dairy cows. Production variables that prolong dairy cow longevity include higher milk yield and an extended calving interval. Findings from this study imply that the relatively short longevity of dairy cows in Sweden compared with some dairy producing countries is not a result of problems with health and welfare. Rather, dairy cow longevity in Sweden hinges on the farmers' investment decisions, farm-specific characteristics and animal management practices.
奶农淘汰或保留奶牛的决定可能是基于动物健康和农场管理实践的复杂决策。本文利用瑞典奶牛场和 2009 年至 2018 年的生产数据，通过控制农场特定特征和动物管理实践，研究了奶牛寿命与动物健康以及寿命与农场投资之间的关系。我们使用普通最小二乘法和无条件分位数回归模型分别进行了基于均值和基于异质性的分析。研究结果表明，平均而言，动物健康对奶牛群寿命有负面影响，但不显著。这意味着淘汰主要是出于健康状况以外的其他原因。农场基础设施投资对奶牛群寿命有积极且显著的影响。农场基础设施的投资为新的或更好的后备小母牛提供了空间，而无需淘汰现有的奶牛。延长奶牛寿命的生产变量包括更高的产奶量和更长的产犊间隔。本研究的结果表明，与一些奶牛生产国相比，瑞典奶牛的相对寿命较短并不是健康和福利问题的结果。相反，瑞典奶牛的寿命取决于农民的投资决策、农场特定特征和动物管理实践。
