Food selection and preference in grazing cattle

放牧牛的食物选择和偏好

• 批准号: RGPIN-2020-05624
• 负责人: Bergeron, Renée
• 金额: $ 2.04万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=743551
• 关键词: Food; selection; preference; grazing; cattle

Pasturing is the most natural and welfare friendly way to feed dairy animals, and is a requirement in organic dairying. Products labelled as "grass-fed" are making an appearance in grocery stores, reflecting a growing demand from consumers conscious about the health benefits of milk from pastured cows, or concerned about animal welfare. Achieving high levels of animal performance and health from grazed forage is a key objective within most pasture-based, milk production systems. Over the last five years, supported by my NSERC Discovery Grant, I studied dairy cows and heifers in pasture-based production systems, with the intent of improving their welfare and efficiency, through better productivity and health. We investigated how grazing behaviour developed in young heifers, looking at the effect of age of introduction to pasture and studying the role of their social environment. We also investigated the effect of gastrointestinal parasites on animal preference for certain types of forages rich in beneficial tannins. The long-term objective of this research program is to advance our understanding of feeding preference and grazing behaviour of heifers and cows in a pasture-based production system. This long-term objective will be achieved through a series of short-term objectives, which aim to determine how feeding preferences and grazing behaviour 1) are related to animal health and productivity; 2) are influenced by forage characteristics; 3) can be modified by early experience and learning. In a first experiment, we will relate individual differences in grazing behaviour and herbage intake with health and productivity. In a second experiment, we will investigate whether the preference for high-tannin forages in response to infection with gastrointestinal nematodes is innate, or acquired following positive post-ingestive consequence. In a third experiment, we will explore voluntary intake and preference of dairy heifers for forages with potential nutraceutical properties, varying in their condensed tannin content. In a fourth experiment, we will investigate the effects of forage condensed tannin levels on cow preference, independently of other characteristics and chemical components, such as fibre, which has been shown to negatively affect preference. A fifth experiment will aim to confirm the existence of a sensitive period for the development of grazing behaviour and efficiency in heifers. Our last experiment will expose young animals to fresh plant species at various stages of development in an attempt to detect a sensitive period for learning plant characteristics. Providing cows with access to pasture is a privileged way to improve animal welfare and the image of the dairy industry. However, maintaining cow productivity and health in a more extensive pasture-based system necessitates an efficient use of forage resources, through an improved knowledge of feeding behaviour and dietary choices, and the development of effective solutions.

放牧是最自然和福利友好的方式来喂养奶牛动物，是有机乳品业的要求。贴上“草饲”标签的产品开始出现在杂货店，反映出消费者越来越意识到奶牛牛奶的健康益处，或关心动物福利。从放牧饲料中获得高水平的动物性能和健康是大多数以牧场为基础的牛奶生产系统的关键目标。在过去的五年里，在我的NSERC发现补助金的支持下，我研究了牧场生产系统中的奶牛和小母牛，目的是通过提高生产力和健康来改善它们的福利和效率。我们调查了放牧行为如何在年轻的小母牛，在引进牧场的年龄的影响，并研究他们的社会环境的作用。我们还研究了胃肠道寄生虫对动物对富含有益单宁的某些类型的饲料的偏好的影响。 这项研究计划的长期目标是促进我们的饲养偏好和放牧行为的小母牛和奶牛在牧场为基础的生产系统的理解。这一长期目标将通过一系列短期目标来实现，这些目标旨在确定喂养偏好和放牧行为如何：1）与动物健康和生产力相关; 2）受饲料特性的影响; 3）可以通过早期经验和学习进行修改。 在第一个实验中，我们将与健康和生产力的放牧行为和牧草摄入量的个体差异。在第二个实验中，我们将调查是否偏好高单宁饲料的胃肠道线虫感染的反应是先天的，或收购后积极的摄食后果。在第三个实验中，我们将探讨自愿摄入量和偏好的奶牛与潜在的营养特性的牧草，不同的缩合单宁含量。在第四个实验中，我们将研究饲料缩合单宁水平对奶牛偏好的影响，独立于其他特征和化学成分，如纤维，这已被证明会对偏好产生负面影响。第五项实验旨在确认小母牛放牧行为和效率发展的敏感期。我们的最后一个实验将在不同的发育阶段将年轻的动物暴露于新鲜的植物物种，试图检测学习植物特征的敏感期。为奶牛提供牧场是改善动物福利和乳制品行业形象的一种特殊方式。然而，在更广泛的牧场系统中保持奶牛的生产力和健康需要通过提高对饲养行为和饮食选择的认识以及制定有效的解决方案来有效利用饲料资源。