American Institute for Goat Research, Langston University, Langston, OK 73050, USA.
J Anim Sci. 2010 Jan;88(1):361-73. doi: 10.2527/jas.2009-2332. Epub 2009 Sep 25.
Factors influencing the feeding behavior of goats include grazing management practices, type of vegetation and season, breed and stage of production, group size, and properties of diets fed in confinement. Considerable information has been gathered from visual observation during daylight. However, tools are now available to characterize the feeding behavior of goats while grazing and while in confinement throughout the day. Global positioning system collars can be used to assess horizontal and vertical distances traveled, up or down position of the head, and movement within pasture or rangeland areas. A commercially available leg activity monitor allows estimation of the number of steps and time spent standing, lying, and moving rapidly without grazing. However, these measurements do not directly determine grazing. Therefore, prediction equations based on visual observation must be developed. Classification tree analysis is a robust method in developing these equations because the decision tree can be pruned or expanded to provide the best fit. Another equipment system determines time spent eating, ruminating, and remaining idle from the pattern of jaw movement. In addition to use of n-alkanes as internal markers to estimate digestibility, their profile can provide an indication of the botanical composition of the selected diet. Automated feeding systems for confined goats permit determinations such as number of feeder visits and meals, eating time, and rate and pattern of feed intake. Heart rate measured while goats are in normal production settings can be used to predict total energy expenditure through multiplication by energy expenditure per heartbeat of individual animals. To partition the activity energy cost, an estimate of ME intake or measures of changes in body energy status and milk energy yield are needed to determine other sources of heat to be subtracted from total energy expenditure. These methods create the opportunity to gain a fuller understanding of factors influencing the feeding behavior of goats and the relationships with levels and efficiencies of production.
影响山羊采食行为的因素包括放牧管理制度、植被类型和季节、品种和生产阶段、群体大小以及舍饲日粮的特性。人们已经从白天的视觉观察中收集到了大量信息。然而，现在已经有工具可以在放牧和舍饲时全天描述山羊的采食行为。全球定位系统项圈可用于评估水平和垂直行进距离、头部上下位置以及牧场或放牧地内的运动。一种市售的腿部活动监测器可用于估计步数和站立、躺卧以及快速移动而不采食的时间。然而，这些测量并不能直接确定采食。因此，必须基于视觉观察来开发预测方程。分类树分析是开发这些方程的一种强大方法，因为决策树可以修剪或扩展以提供最佳拟合。另一种设备系统根据下颌运动模式确定采食、反刍和空闲时间。除了使用正烷烃作为内部标记来估计消化率外，它们的分布还可以指示所选日粮的植物组成。用于限制饲养山羊的自动饲喂系统允许确定例如饲槽访问和采食次数、采食时间以及采食速度和模式。在正常生产环境下测量的心率可用于通过乘以个体动物每心跳的能量支出来预测总能量支出。为了划分活动能量成本，需要估计 ME 摄入量或测量体能量状态和乳能量产量的变化，以确定要从总能量支出中减去的其他热源。这些方法为深入了解影响山羊采食行为的因素以及与生产水平和效率的关系提供了机会。
