Data from: Controlled feeding experiments with diets of different abrasiveness reveal slow development of mesowear signal in goats (Capra aegagrus hircus)

Dental mesowear is applied as a proxy to determine the general diet of mammalian herbivores based on tooth-cusp shape and occlusal relief. Low, blunt cusps are considered typical for grazers and high, sharp cusps typical for browsers. However, how internal or external abrasives impact mesowear, and the time frame the wear signature takes to develop, still need to be explored. Four different pelleted diets of increasing abrasiveness (lucerne, grass, grass and rice husks, grass, rice husks and sand) were fed to four groups of a total of 28 adult goats in a controlled feeding experiment over a six-month period. Tooth morphology was captured by medical CT scans at the beginning and end of the experiment. These scans, as well as the crania obtained postmortem, were scored using the mesowear method. Comparisons between diet groups only showed few significant differences after six months, irrespective of whether CT scans or the real teeth were scored. Only when assessing the difference in signal between start and end did relevant, significant diet-specific effects emerge. Diets containing lower phytolith content caused a more pronounced change in mesowear towards sharper cusps/higher reliefs, while the feed containing sand did not result in more extreme changes in mesowear when compared to the same feed without sand. Our experiment suggests that the formation of a stable and hence reliable mesowear signal requires more time to develop than six months.牙齿磨耗特征分析法（dental mesowear）是一种以牙尖形态（tooth-cusp shape）与咬合面起伏（occlusal relief）为依据，用以推断植食性哺乳动物整体食性的替代分析方法。低平圆钝的牙尖是草食性放牧动物的典型特征，而高锐尖锐的牙尖则为取叶植食动物所特有。然而，内外磨蚀因子如何影响牙齿磨耗特征，以及磨耗特征形成所需的时间窗口，仍有待进一步探究。 本研究开展了一项为期六个月的可控饲喂实验，将四种磨蚀性逐级递增的颗粒饲料分别饲喂于四组共计28只成年山羊，四种饲料依次为紫花苜蓿、青草、青草与稻壳、青草+稻壳+沙子。实验开始与结束阶段，均通过医用CT扫描采集山羊的牙齿形态数据。研究人员采用牙齿磨耗特征分析法，对上述CT扫描影像以及实验结束后获取的头骨样本进行评分。 仅比较各组间的差异时，无论基于CT扫描影像还是真实牙齿进行评分，六个月实验周期后各组间仅存在少量显著差异。唯有对比实验起始与结束阶段的磨耗信号差异时，才会显现出与日粮相关的显著特异性效应。植硅体（phytolith）含量较低的日粮会使牙齿磨耗特征向牙尖更尖锐、咬合面更高起伏的方向发生更为显著的变化；而相较于未添加沙子的同日粮，添加沙子的饲料并未导致牙齿磨耗特征出现更为极端的改变。 本实验表明，要形成稳定且可靠的牙齿磨耗特征信号，所需的时间远超六个月。