Impact of a molasses-based liquid feed supplement on the diet selection behaviour and growth of cattle fed a feedlot diet

为了确保肉牛饲养场牛的持续摄入和生长，开发了一种新的育肥牛饲养策略，该策略将高能量、高蛋白液体饲料补充剂纳入低饲料、肉牛饲养场饮食中。该饲喂策略的关键特征之一是使围栏内的所有动物保持一致的饲料和谷物摄入量。饲养场口粮某些成分的饮食选择（排序）有可能导致营养摄入量不平衡。因此，本研究的目的是确定添加基于糖蜜的液体饲料补充剂对饲喂饲养场肥育日粮的年轻牛的饮食选择行为和生长的影响。我们假设，在饲养场饮食中添加基于糖蜜的液体饲料将减少对长纤维颗粒的分选量，从而降低营养消耗的变化，并提高围栏内所有牛的生长一致性。为了验证这一假设，将对24头雄性荷斯坦牛进行研究。研究开始时，牛将为84日龄（体重约125 kg）。将牛分为6组，每组4头小牛，年龄和体重平衡。然后将各组以交叉设计（35天周期）暴露于两种处理中的每一种：1）对照饮食（76%玉米，19%蛋白质补充剂，5%饲料）和2）添加10%糖蜜基液体饲料的对照饮食。整个研究期间将监测摄食量、饮食选择、摄食行为、生长和健康状况。这项研究不仅将为液体饲料国际（1986）有限公司提供这种新的饲养策略的经验支持，以确保牛肉饲养场牛的一致摄入量和生长，而且还补充了圭尔夫大学的研究，创造了影响牛饲养行为的表达和生理后果的因素的基础知识。这项研究的主要受益者是加拿大的养牛者，他们实施这项喂养计划，以降低饲料成本，提高牛的健康、效率和福利。

A new feeding strategy for fattening cattle, which incorporates high-energy, high-protein liquid feed supplement in a low-forage, beef feedlot diet, has been developed with the intent of ensuring consistent intakes and growth in beef feedlot cattle. One of the key features of this feeding strategy is to maintain a consistent intake of both forage and grain in the formulated amounts, for all animals within a pen. Dietary selection (sorting) for certain components of feedlots rations has the potential to cause imbalances in nutrient intakes. Thus, the objective of this research is to determine the impact of adding a molasses-based liquid feed supplement on the diet selection behaviour and growth of young cattle fed a feedlot finishing diet. We hypothesize that adding a molasses-based liquid feed to a feedlot diet will decrease the amount of sorting against the long-fibrous particles, thus decreasing variability in nutrient consumption, and improving consistency of growth across all cattle within a pen. To test this hypothesis, 24 male Holstein cattle will be studied. At the beginning of the study, cattle will be 84 d of age (with a body weight of ~125 kg). Cattle will be placed into 6 groups of 4 calves, balanced for age and weight. Groups will then be exposed, in a crossover design (with 35 d periods) to each of two treatments: 1) control diet (76% corn, 19% protein supplement, 5% forage) and 2) control diet with 10% molasses-based liquid feed added. Feed intake, diet selection, feeding behaviour, growth, and health will be monitored throughout the study. This research will not only provide Liquid Feeds International (1986) Ltd. with empirical support for this new feeding strategy for ensuring consistent intakes and growth in beef feedlot cattle, but also complement research at the University of Guelph in creating fundamental knowledge on the factors influencing the expression and physiological consequences of feeding behaviour in cattle. The primary beneficiaries of this research are Canadian cattle producers who implement this feeding program in effort to reduce feed costs, and improve the health, efficiency and welfare of their cattle.