To prevent mastitis caused by inappropriate milking systems, inspection of the system, and maintenance of optimal function are crucial. This study aimed to clarify the problems with milking systems in Japan by analyzing the results of milking system inspections over the past 21 years. A total of 190 dairy farms (358 systems; 153 high-line systems, 205 low-line systems) were inspected for the checkpoints of problems originating from installation (PI) or problems originating from insufficient maintenance (PIM). Results were divided into initial and periodic inspections, then analyzed by year of inspection or years elapsed since equipment installation. With increasing years, inadequacy of milk piping and regulator maintenance tended to increase for high-line systems. On the other hand, defects in milking units tended to increase for low-line systems. This difference was attributed to the structures of these milking systems. The present study revealed potential problem areas in high- and low-line milking systems from recent years. To maintain normal functioning in milking systems, the frequency and content of inspections as currently being conducted need to be reviewed.

中文翻译：

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日本奶牛场 21 年挤奶系统检查结果分析。

为防止因挤奶系统不当引起的乳腺炎，检查系统和维持最佳功能至关重要。本研究旨在通过分析过去 21 年的挤奶系统检查结果来阐明日本挤奶系统存在的问题。共检查了 190 个奶牛场（358 个系统；153 个高线系统，205 个低线系统），检查安装问题（PI）或维护不足问题（PIM）的检查点。结果分为初始检查和定期检查，然后按检查年份或设备安装后经过的年数进行分析。随着时间的推移，高压线系统的牛奶管道和调节器维护不足趋于增加。另一方面，对于低线系统，挤奶装置的缺陷往往会增加。这种差异归因于这些挤奶系统的结构。本研究揭示了近年来高线和低线挤奶系统中的潜在问题领域。为了维持挤奶系统的正常运作，需要审查目前进行的检查的频率和内容。