We compared cow-calf contacts, as well as movement, activity, and pasture use patterns of heritage Raramuri Criollo (RC) and desert-adapted commercial Angus Hereford crossbred (AH) beef cattle grazing Chihuahuan Desert pastures during 4 wk in the summers of 2016 and 2017. Within each herd of 11 cow-calf pairs, a group of 7−9 randomly selected cows were fitted with Global Positioning System collars that recorded animal position at 10-min intervals. Proximity loggers configured to record contact events (< 1-m radius) were fitted on a subset of five cow-calf pairs of each breed. The effect of breed on cow-calf contacts, as well as the dams’ movement, activity, and pasture use patterns were analyzed via mixed analysis of variance models. A higher number of RC cow-calf contacts occurred while the dam was grazing and traveling compared with AH counterparts (P ≤ 0.05). No breed-related differences were observed in the overall number and duration of cow-calf contact events. Compared with AH dams, RC cows traveled farther each day (RC: 7.51 vs. AH: 4.85 km, P < 0.01) at higher movement velocities (5.46 vs. 3.53 m. min⁻¹, P < 0.01) and spent more time traveling (1.05 vs. 0.48 h, P < 0.01), more time grazing (9.37 vs. 7.45 h, P < 0.01), and less time resting (13.07 vs. 15.68 h, P < 0.01). RC cows explored almost three times more daily area than AH (152.30 vs. 57.69 ha, P = 0.01) but spent similar amounts of time within 200 m and 100 m of a drinker. RC calves explored larger daily areas than their AH counterparts (83.0 vs. 20.8 ha, P = 0.05), but no breed differences were detected in the number of contact events near drinkers. RC calves possibly impose fewer constraints on their dams’ movement and activity patterns compared with commonly used British crossbreds when grazing the Chihuahuan Desert during summer.

我们比较了2016年夏季4周内放牧奇瓦瓦沙漠牧场的传统Raramuri Criollo（RC）和适应沙漠化的商业安格斯Hereford杂交（AH）肉牛的小牛接触，运动，活动和牧场使用方式和2017年。在每对11对牛犊中，有7-9头随机选择的牛被装配了全球定位系统项圈，以10分钟的间隔记录动物的位置。将配置为记录接触事件（半径小于1米）的接近记录器安装在每个品种的五头小牛犊对的子集中。通过方差模型的混合分析，分析了品种对牛犊接触的影响以及大坝的运动，活动和牧场使用方式。P ≤0.05）。在牛犊牛接触事件的总数和持续时间上未观察到与品种相关的差异。与AH大坝相比，RC奶牛每天以更高的运动速度（5.46 vs. 3.53 m。min ^-1，P <0.01）走得更远（RC：7.51 vs. AH：4.85 km，P <0.01），并花费更多的时间旅行（1.05 vs. 0.48 h，P <0.01），放牧时间更多（9.37 vs. 7.45 h，P <0.01），休息时间更少（13.07 vs. 15.68 h，P <0.01）。RC奶牛的每日探索面积几乎是AH的三倍（152.30比57.69公顷，P = 0.01），但在饮酒者200 m和100 m内花费了相似的时间。RC小牛的日面积比其AH小牛大（83.0比20.8公顷，P  = 0.05），但在饮酒者附近的接触事件数量上未发现品种差异。与夏季放牧奇瓦瓦沙漠时常用的英国杂交品种相比，RC小牛可能对水坝的活动和活动方式施加的约束更少。