Development of an automatic measuring system for recording the number of tail swishing against pest flies in grazing cattle

摘要

In this study, we developed a portable automatic measuring system for recording the number of tail swishing against pest flies in grazing cattle. Four Japanese Black cattle were monitored as focal animals from August to October, and the number of their tail swishing was recorded for 21 hours with the developed measuring system each month. Simultaneously, an individual observer followed each focal animal for 6 hours from 9 : 00 to 15 : 00 in the pasture and the number of tail swishing was recorded continuously. Then, we compared the numbers of tail swishing by the measuring system and direct observation focal animal sampling. The measuring system could record the number of tail swishing continuously for 21 hours. The number of tail swishing recorded by the measuring systems was higher than by direct observation, and the mean difference in tail swishing was 8.6 percent. The present study suggested that the developed system was a useful device for recording the number of tail swishing in the grazingcattle, although a corrective factor may need to be applied to the results.