Skevas T, Cabrera V E
Division of Applied Social Sciences, University of Missouri, Columbia 65211.
Department of Dairy Science, University of Wisconsin, Madison 53706.
J Dairy Sci. 2020 Dec;103(12):12117-12127. doi: 10.3168/jds.2020-18656. Epub 2020 Oct 1.
This study measures the dynamic technical and udder health management inefficiencies of a sample of Wisconsin dairy farms. Udder health management inefficiency is defined as a farmer's failure to achieve lower levels of milk somatic cell counts compared with those of the best-practice farmers within the sample. The study proposes the treatment of somatic cell count as an undesirable output. We measured inefficiency using a dynamic directional distance function that accounts simultaneously for the expansion of desirable outputs and investments in capital assets, and contraction of undesirable output and variable inputs. In a second step, a bootstrap truncated regression was used to analyze factors that cause differences in dynamic technical and udder health management inefficiencies. Results showed that the sample farmers had considerably higher udder health management inefficiency scores than technical inefficiency scores. The results of the second-stage analysis indicated that technical inefficiency was influenced by summer precipitation and farmers' financial characteristics, and was regionally heterogeneous. Udder health management inefficiency was affected by summer temperature and nonfarm income. By ranking farms in this study in terms of technical and udder health management inefficiency, we allowed inefficient farms to compare their performance with that of their efficient peers, and thus identify targets for production and udder health management improvement efforts. Finally, although our study focused on farmers' performances with respect to udder health management, the proposed modeling framework can be applied to the management of other animal diseases and welfare conditions.
本研究衡量了威斯康星州奶牛场样本的动态技术和乳房健康管理效率低下情况。乳房健康管理效率低下被定义为与样本中最佳实践养殖户相比，养殖户未能实现更低水平的牛奶体细胞计数。该研究提出将体细胞计数视为非期望产出。我们使用动态方向距离函数来衡量效率低下情况，该函数同时考虑了期望产出的扩大和资本资产投资，以及非期望产出和可变投入的收缩。在第二步中，使用自助截尾回归分析导致动态技术和乳房健康管理效率低下存在差异的因素。结果表明，样本养殖户的乳房健康管理效率低下得分远高于技术效率低下得分。第二阶段分析结果表明，技术效率低下受夏季降水量和养殖户财务特征的影响，且存在区域异质性。乳房健康管理效率低下受夏季温度和非农业收入的影响。通过在本研究中按技术和乳房健康管理效率低下对养殖场进行排名，我们使效率低下的养殖场能够将其绩效与其高效同行的绩效进行比较，从而确定生产和乳房健康管理改进努力的目标。最后，尽管我们的研究侧重于养殖户在乳房健康管理方面的表现，但所提出的建模框架可应用于其他动物疾病和福利状况的管理。
