摘要
Feed efficiency is a necessary factor in beef production systems due to rising feed ingredient costs, population growth, and beef supply demands. With this known, it is important for researchers to delve into mechanisms involved in efficiency to provide producers with a knowledge base for future selection and breeding programs. Though the use of residual feed intake (RFI) is fairly well know, traditional traits are often considered more desirable due to costs associated with testing. However, previous research has provided evidence of benefits using a less biased measurement (RFI) in comparison with its counterparts (e.g. ADG, FCR, F:G etc...) Though RFI does provide indication of efficiency status, there are underlying mechanisms that also play a role in these measurements that are not completely understood. One attribute of efficiency often overlooked is feeding behavior, in which this body of work attempts to interpret via relationships with RFI. Previous research has provided has examined relationships between these two parameters, however further studies are necessary to gain a more solid foundation. Research within this dissertation will add to this knowledge base using two breeds of cattle examined for behavior traits (bunk visit frequency, bunk visit duration, feed bout frequency, feed bout duration, meal frequency, meal duration, and average meal intake) during the course of RFI evaluation. Niche breeds of beef cattle (e.g. Japanese Black Cattle) are often excluded from feed efficiency examinations, due to focuses of output, carcass quality traits, and increased specialty market value. However, the recent rise of feed ingredient costs are universal, and producers of niche breeds may benefit as well. Within this body of work, 3 cohorts of Wagyu cattle were evaluated for feeding behavior parameters with some insight towards relationships with efficiency. Red Angus cattle were also evaluated over both growing and finishing phase RFI to clarify feeding behaviors' role in efficiency. Results from these studies provide researchers with additional tools for elucidating these relationships as well as identifying specific feeding behaviors that contribute to efficiency status in beef cattle.
摘要译文
饲料效率是牛肉生产体系的必要因素，由于上涨的饲料原料成本，人口增长和牛肉供应的需求。与这种已知的，为研究人员钻研参与效率为生产商提供的知识库以供将来选择和育种计划的机制是很重要的。虽然使用剩余采食量（RFI）是相当众所周知，传统的特征通常被认为是更可取的，由于与测试相关的成本。利益与同行（如日增重，饲料转化率，F：G等）相比使用较少偏见的测量（RFI）。然而，以往的研究提供的证据虽然RFI确实提供了效率状态指示，也有潜在的机制，也起到在这些测量中未完全了解的作用。效率的一个属性经常被忽略的摄食行为，在这个机构的工作试图通过与RFI的关系来解释。以前的研究提供了审查这两个参数之间的关系，但是需要进一步的研究，以获得更坚实的基础。本文中作者将添加到使用牛检查的行为特征（双层访问频率，双层访问持续时间，饲料回合频率，饲料回合持续时间，频率一顿，一顿持续时间和平均摄食）两个品种的过程中，这个知识库RFI评价。肉牛（如黑毛日本牛）的利基品种往往被排除在饲料效率的考试，由于产量，胴体品质性状，并增加专业市场价值的重点。然而，近期饲料原料成本的上升是普遍的，和特殊品种的生产商可能会受益。在这个机构的工作，神户牛3同伙进行了评价与对与效率关系的一些见解摄食行为的参数。红安格斯牛人也评估了两种生长肥育阶段RFI澄清取食行为效率的作用。这些研究结果为研究人员提供了阐明这些关系以及确定具体的摄食行为，在肉牛有助于效率状态的其他工具。
McGee, Marcus. Residual feed intake in beef cattle; in relation to breed, selection, and behavior[D]. US: University of Idaho, 2014