Early relationships between young mammalian herbivores and social models (e.g., mothers or peers) have been proposed as playing a major role in the process of diet learning. Diet selection is an important factor influencing animal development and ecology, especially in natural and seminatural grasslands, with a large diversity of plant species. To explore the learning process of foraging behavior and diet selection choices by foals, six free-ranging Criollo foals and their respective mares were monitored through continuous bite monitoring from birth to 130 d old, in the Pampas Grasslands of southern Brazil. Cumulative suckling time decreased exponentially from birth to 130 d old, while dry matter intake, foraging time, and bite mass of foals increased continuously. It was possible to identify three marked periods in the foal’s foraging behavior development: 1) an exploratory phase (from 0 to 40 d old) marked by limited forage intake from a large diversity of plants; 2) a specialization phase (from 40 to 110 d old) with a marked increase in forage intake and a specialization around the same plants as the ones selected by the mares; and 3) a stabilization phase (after 110 d old) in which forage intake still increases but diet composition of foals stabilized similarly to the one of the respective mares. The higher diversity at young ages could be explained by exploratory hypothesis, where foals test different forages to discover their environment, given that their nutritional needs are fulfilled by milk consumption, not by forage intake. As requirements shift toward solid items, bite mass and foraging time increase and diet choices become similar to that of the mares. Our results detail how young foals develop their foraging behavior and suggest, without testing it and under the circumstances of this study, that they learn their diet through social transmission from their mothers.

幼小的哺乳动物食草动物和社会模型（例如母亲或同伴）之间的早期关系被认为在饮食学习过程中起着重要作用。饮食选择是影响动物发展和生态的重要因素，尤其是在自然和半自然草原中，植物种类繁多。为了探索小马驹觅食行为和饮食选择选择的学习过程，在巴西南部的潘帕斯草原，通过连续咬入监测从出生到130天大的时间，对六只自由放养的Criollo小马驹及其母马进行了监测。从出生到130 d龄，累计哺乳时间成倍减少，而干物质的摄入，觅食时间和小马驹的叮咬质量不断增加。探索阶段（0至40 d龄），其特征是来自多种植物的饲料摄入有限；2）专业化阶段（从40到110 d龄），饲草采食量显着增加，并且在与母马选择的植物相同的植物周围进行专业化处理；和3）稳定阶段（110 d龄之后），其中饲草摄入量仍增加，但小马驹的饮食组成与相应母马中的一只相似。探索性假设可以解释年轻时期较高的多样性，在这种假设中，小马驹测试不同的草料以发现其环境，因为它们的营养需求是通过食用牛奶而不是通过摄取草料来满足的。随着需求转向固体食物，叮咬质量和觅食时间增加，饮食选择也与母马相似。我们的研究结果详细说明了小马驹如何发展其觅食行为，并且在没有进行测试的情况下，并且在本研究的情况下，建议他们通过母亲的社交传播来学习饮食。