Ergonomic evaluation of hand and mechanized milking in dairy farms

Despite the introduction and development of agricultural mechanization in the dairy farm sector of Iran, many tasks are still performed by manual labor in the country’ dairy farms, including milking, and necessitate poor body postures and movements that help increase the risk of musculoskeletal disorders among hand milking workers. The present study was conducted to assess the postural workload of workers during hand milking in the dairy farms of Ramin Agriculture and Natural Resources University and Ramhormoz county. Three milking techniques were assessed, including traditional hand milking, milking stanchion (mobile milking unit) and tandem parlor milking (the double-3 tandem). The postural workloads of 34 male milking workers were evaluated through mixed-methods. The results obtained showed that hand and stanchion milking require major parts of the body to be in a bent position over 70% of the time due to the operations taking place at a low height from the ground. In contrast, tandem milking required the body to be in a straight position over 90% of the time due to the operations taking place at a substantial height from the ground. Moreover, in terms of finger posture, all three techniques required the workers’ five fingers to be wrapped around different milking tools and parts of the cattle throughout the processes. Being bent for long periods of time during the process of hand and stanchion milking and standing upright for long periods during tandem milking both caused musculoskeletal disorders of the back and backache for workers of both traditional and mechanized milking. In the case of the finger posture, prolonged repetitive finger postures decrease for milking workers with the increased mechanization of milking.