ABSTRACT

1. This experiment was conducted to evaluate the effect of organic and inorganic trace minerals in diets fed to 1872, one-day-old male Ross 708 broiler chicks. Two sources of supplemental trace minerals (inorganic or organic) and four trace minerals levels (12.5%, 25.0%, 37.5% or 50.0%) plus a positive control containing inorganic minerals at 100% of recommended levels according to Brazilian industry standards, were used in the diets.

2. When analysed with mineral source as the main factor, broilers fed diets containing organic minerals had better feed conversion (FCR) throughout the trial, until 48 d of age (1.754 organic vs. 1.783 inorganic; P < 0.05), improved liveability at 48 d (95.8% organic vs. 93.6% inorganic; P < 0.05) and higher weight gain at 48 d (3.941 kg organic vs. 3.881 kg inorganic; P < 0.05) compared to the inorganic trace mineral diets. At lower dietary inclusion levels (12.5% and 25%) the organic mineral-fed birds had a four-point improvement in FCR (P < 0.05).

3. Feeding organic minerals improved tibial ash at 48 d from 49.5% to 51.25% (P < 0.05). The P and Ca in the tibia at 48 d were significantly (P < 0.05) higher for the birds fed organic minerals (Ca: 17.4% vs. 18.7%; P: 8.8% vs. 9.4%, respectively). The lower levels of trace minerals in feed reduced the mineral concentration of Zn, Cu and Mn in the faeces and, hence, in the litter (P < 0.05).

4. Feeding organic minerals promoted a small, but statistically significant, drop in pH of breast meat compared to inorganic minerals at 48 d (5.83 vs. 5.86, respectively; P < 0.05). The organic mineral diets reduced drip loss in breast meat compared to inorganic trace mineral supplementation at 32 d of age, but not in older birds (2.46% vs. 3.77%, respectively; P < 0.05).

5. Oxidation status, measured by superoxide dismutase activity in breast muscle at 48 d of age, significantly increased with mineral inclusion levels (P < 0.001), irrespective of source.

6. It was concluded that the use of organic minerals, even at low levels in the diet, is beneficial for broiler performance and reduces the excretion of minerals in litter.

摘要

1.进行该实验以评估有机和无机微量矿物质对1872日龄雄性Ross 708肉鸡的饲喂日粮的影响。根据巴西工业标准，使用了两种补充微量矿物质（无机或有机）和四种微量矿物质水平（12.5％，25.0％，37.5％或50.0％）以及一个阳性对照，其中包含的无机矿物质含量为巴西工业标准推荐水平的100％。在饮食中。

2.当以矿物质为主要因素进行分析时，饲喂含有机矿物质的日粮的肉鸡在整个试验过程中具有更好的饲料转化率（FCR），直到48 d龄（1.754有机物对1.783无机物； P <0.05），在与无机微量矿物质日粮相比，在48天时（95.8％有机vs. 93.6％无机； P <0.05）和在48天时体重增加（3.941 kg有机vs. 3.881 kg无机； P <0.05）更高。在较低的饮食包含水平下（分别为12.5％和25％），有机矿物质饲喂的家禽的FCR改善了4点（P <0.05）。

3.饲喂有机矿物质可使胫骨灰分在48 d时从49.5％增至51.25％（P <0.05）。饲喂有机矿物质的家禽在48 d时胫骨中的P和Ca显着较高（P <0.05）（Ca：17.4％vs . 18.7％; P：8.8％vs . 9.4％）。饲料中痕量矿物质的含量降低，降低了粪便中和垫料中锌，铜和锰的矿物质浓度（P <0.05）。

4.与无机矿物质相比，在48 d时饲喂有机矿物质会导致胸肉pH值小幅下降，但具有统计学意义（分别为5.83和5.86； P <0.05）。与添加32 d无机微量矿物质相比，有机矿物质饮食减少了胸肉的滴水损失，但在成年禽中则没有（分别为2.46％和3.77％； P <0.05）。

5.氧化状态（通过48天龄的乳房肌肉中的超氧化物歧化酶活性来衡量）随矿物质含量的升高而显着增加（P <0.001），而与来源无关。

6.结论是，即使饮食中的有机矿物质含量较低，也可提高肉鸡的生产性能，并减少垃圾中矿物质的排泄。