电刺激对肉牛行为和生理指标的影响

为研究电刺激对肉牛行为和生理指标的影响，确定约束肉牛放牧边界的作用电压。以内蒙古鄂尔多斯

Effects of the electrical stimulation on the behavioral and physiological performances of the beef cattle

Electrical stimulation has been one of the innovative techniques in grazing management. This study aims to explore the effects of electrical stimulation on the behavioral and physiological performance of the beef cattle. The action voltage was also determined to constrain the grazing boundary of the beef cattle. The ‘Grassland Red’ beef cattle in Ordos were used in the experiments, the electric stimulation was carried out from the lower part of the neck with the beef cattle via wearing the electric shock collar. The beef cattle were allocated to four voltages with 4 66, 1 723, 2 050, 2 865 and 4 204 V at which naïve beef cattle underwent training as experimental groups. An electrical stimulation was administered when the animal entered the exclusion zone, followed by a shock if the beef cattle continued to proceed. The beef cattle were randomly selected for each experimental group and the control group (no electrical stimulation). A wireless Electroencephalogram (EEG) monitoring system was utilized to monitor the body temperature, heart rate, and brain wave of the beef cattle before and after different electric stimulation. In the experimental arena, three beef cattle were fed in an experimental arena with the virtual fence boundary line, and their body behaviors were recorded by a camera system synchronously. A behavior observation and Analysis Software was selected to analyze the behavior characteristics of the beef cattle (turning round, stopping, stop and slowly turn back, stop moving and back immediately, and skip, flick, blink, shake head). Results showed that there was no significant change in the body temperature of the beef cattle before and after different electric stimulation. Specifically, while the voltage was set to 466, 1 723 and 2 050 V, the heart rate of beef cattle before and after electrical stimuli did not change significantly. Once the beef cattle were subjected to the electrical stimulation at 2 865 and 4 204 V, the heart rate increased significantly by 26.3% and 35.3%, which were reached 104.32 and 108.83 bpm, respectively. By contrast, there were small changes in the β-wave of electroencephalogram (EEG) before and after electrical stimulation at 466 and 1 723 V, respectively, but dramatic changes were found over 2 865 V. The frequency that the beef cattle triggered the virtual boundary with 2 865 V electrical stimulation was 93 times, of which the total behaviors of turning round, stopping, stop and slowly turn back, stop moving and back immediately accounted for 33.33%, 12.02%, 9.29%, and 31.69%, respectively. When 4 204 V was used for electrical stimulation, the performances of all behaviors accounted for 38.60%, 5.12%, 19.07%, and 21.86%. Overall, the electrical stimuli of 2 865 V could effectively prevented the beef cattle to cross the boundary and to enter the exclusion zone. Our research results can provide a strong reference and application potential for beef cattle grazing management in grassland.