Enhancing digestion efficiency and weaning success of dairy calves through provision of a novel calf starter

向奶牛犊牛提供更多的牛奶已被证明可以改善犊牛的短期和长期生产性能和效率，以及整体福利。喂养高水平牛奶的一个挑战是成功地戒掉牛奶。由于小牛对牛奶有天然的偏好，当他们在两者之间做出选择时，他们会倾向于消耗牛奶而不是固体饲料。因此，饲喂高水平的牛奶可以减少断奶前犊牛消耗的固体饲料量。断奶对犊牛的生理和行为都有不利影响。为了帮助缓解断奶压力，犊牛在脱乳前摄入足量的固体饲料，以促进瘤胃发育，并在这一饮食过渡期间保持健康和生产性能，这一点非常重要。这需要一个适当的断奶方案，以及在这段时间内饲喂高度可口和易于消化的饲料。因此，本项目的目的是确定饲喂一种新型的基于牛奶副产品（乳清）的犊牛发酵剂对犊牛生长、效率和福利的影响。将进行一项随机研究，以验证以下假设：与仅饲喂传统谷物型犊牛发酵剂的犊牛相比，饲喂以牛奶副产品为基础的犊牛发酵剂的犊牛在生命中更早开始摄入固体饲料，瘤胃发育更快，断奶后消化效率更高。这样的研究对专门从事动物营养和饲料产品以支持动物性能的格兰德谷强化公司很重要。健全的科学研究调查这种新型饲料产品的影响是必不可少的，对于大峡谷强化剂能够自信地建议他们的客户如何最好地喂养小牛在生命的早期。这项研究还将补充圭尔夫大学的研究，发现犊牛从牛奶转向固体饲料时影响生理变化的因素。具体来说，这项研究将为一种潜在的新饲料提供新的见解，以促进小牛的采食量和降低断奶成功率。这项研究的主要受益者是加拿大的乳制品生产商，他们可以利用这种饲料来优化奶牛的生长、健康和福利。

Provision of higher quantities of milk to dairy calves has been shown to improve short- and long-term calf performance and efficiency, and overall welfare. A challenge with feeding higher levels of milk is the successful weaning off that milk. With calves having a natural preference for milk, they will tend to consume milk over solid feed when given the choice between the two. Therefore, feeding higher levels of milk can decrease the amount of solid feed calves consume prior to weaning. Weaning dairy calves off milk is a stressful transition and can have detrimental effects on calf physiology and behaviour. To help ease weaning stress, it is important that calves consume sufficient amounts of solid feed, prior to the removal of milk, for calves to develop their rumen and maintain their health and performance during this dietary transition. This requires a proper weaning protocol as well as the feeding of both a highly palatable and digestible feed during this time period. Thus, the objective of this project is to determine the impact of feeding a novel, milk by-product (whey) based calf starter on the growth, efficiency, and welfare of calves. A randomized study will be conducted to test the hypothesis that calves fed a milk by-product based calf starter will start to consume solid feed earlier in life, experience faster rumen development, and show greater efficiency of digestion post-weaning than calves fed only a traditional grain-based calf starter. Such research is important to Grand Valley Fortifiers, who specialize in animal nutrition, and feed products to support animal performance. Sound scientific research investigating the effects of this novel feed product is essential for Grand Valley Fortifiers to be able confidently advise their clientele on how best to feed calves early in life. This research will also complement research at the University of Guelph in discovering factors influencing physiological changes that occur as calves wean off milk onto solid feed. Specifically, this research will provide novel insight on a potential new feed to offer calves to encourage feed intake and ease weaning success. The primary beneficiaries of this research are the Canadian dairy producers who can utilize this feed to optimize growth, health, and welfare of their dairy calves.