ABSTRACT

1. A trial was conducted to investigate the capacity of broiler chickens to consume bulky feeds during three stages of growth. These phases were from 1 to 15 d, 16 to 30 d and from 31 to 45 d.

2. A basal feed was serially diluted (0%, 2.5%, 5.0%, 10% or 15%) with one of five diluents (cellulose fibre, sawdust, rice husk, sand or vermiculite) to produce 25 feeds which were supplied on an ad libitum basis to the birds in each phase. Cobb 500® strain chicks were used, and, within each phase, each feed was given to nine individually-caged birds, 225 in total, distributed in a completely randomised design.

3. Intake increased initially, and then declined, as the proportion of each diluent increased. The consumption of feeds that limited intake were directly proportional to metabolic body weight and so a scaled feed intake, expressed as g/BW^0.67 per day, was calculated. There were large effects of feed type on intake, in the short term, with consumption of a bulky feed leading to higher intakes.

4. It was concluded the Water Holding Capacity (WHC) content of the feeds could be appropriate measurement of ‘bulk’ responsible for limiting intake and could be used to predict maximum feed intake capacities of broiler chickens fed bulky diets.

摘要

1. 进行了一项试验，以调查肉鸡在三个生长阶段消耗大量饲料的能力。这些阶段是从 1 到 15 天、16 到 30 天和从 31 到 45 天。

2. 用五种稀释剂（纤维素纤维、锯末、稻壳、沙子或蛭石）中的一种对基础饲料进行连续稀释（0%、2.5%、5.0%、10% 或 15%）以生产 25 种饲料，每个阶段的鸟类都可以随意选择。使用 Cobb 500® 品系雏鸡，在每个阶段，每种饲料分别喂给 9 只单独笼养的鸡，总共 225 只，以完全随机的设计分布。

3.随着各稀释剂比例的增加，摄入量先增加后下降。限制采食量的饲料消耗量与代谢体重成正比，因此计算了以 g/BW ^0.67 /天表示的成比例的采食量。在短期内，饲料类型对采食量有很大影响，食用大量饲料会导致采食量增加。

4. 得出的结论是，饲料的持水量 (WHC) 含量可以适当地衡量限制采食量的“体积”，并可用于预测饲喂大块日粮的肉鸡的最大采食量。