Development of a chute for improving cow movement and reducing agonistic behavior

Abstract

The walk-over-weighing (WoW) system and a body weighing system utilizing a dead-end chute have been developed to reduce the labor involved in weighing grazing cows. However, challenges persist, such as abnormal body weight readings in the WoW and agonistic behavior in the dead-end chute system. In this study, the dead-end chute was redesigned with separate entrance and exit routes. The exit was positioned at a 45° outward angle at the other end from the entrance to facilitate movement away from the chute. Six cows with prior dead-end chute experience were used to evaluate the effectiveness of the improved chute design by comparing incidences of agonistic behavior, daily visit frequency, time spent per visit and time spent drinking per day between the improved chute and the dead-end chute. Six cows with no chute experience were used to investigate the learning process in the improved chute. Additionally, using the same 12 cows, we tested whether cows were more likely to use the exit or move backward toward the entrance when using the improved chute. The mean occurrence rate of agonistic behavior was significantly lower in the improved chute than in the dead-end chute. Cows with no experience entered the improved chute independently within 5 days after grazing began. Subsequently, as the number of usage days increased, the time spent per visit decreased, while drinking time was extended. In the improved chute, when no cows were present near the chute, three out of 12 cows used the forward exit; however, when other cows were present near the entrance, 10 cows exited through the exit chute. These findings suggest that the improved chute is effective for the management of grazing cattle.