饲料精粗比对肉牛生长性能、营养物质消化率、血清生化指标的影响

试验探究不同的饲料精粗比对肉牛生长性能、营养物质消化率以及血清生化指标3个方面的影响。选取40头健康状况良好的肉牛分为4组,每组10个重复,分别饲喂基础饲粮,以及精料占比30%、40%、50%的全混饲粮。结果显示,随着精料占比提高,肉牛的生长性能得以提升,以40%精料占比组的肉牛日均增重最多。精料比的升高会导致营养物质消化率的降低,其中30%和40%精料比的肉牛组的表观消化率较基础饲粮的降幅要显著小于50%精料比的肉牛组。血清生化指标结果显示,饲料精粗比的提高可以降低肉牛血糖,促进营养物质的利用,对肉牛肝脏健康情况没有影响,还会提高其总蛋白含量,提升肉牛的机体免疫能力。试验结果表明,选择饲料在40%精料占比条件进行肉牛的饲喂养殖,对生长性能、营养物质消化和利用的效果最好。

玉米秸秆精粗颗粒饲料加工与应用

玉米秸秆与精料混合制成玉米秸秆精粗颗粒饲料的密度比玉米秸秆粉增加10倍,体积减小,便于储存运输。玉米秸秆精粗颗粒可提高奶牛对饲料干物质采食量,并对反刍次数及产奶量无明显影响。

精粗配合颗粒饲料对奶牛纤维性物质和蛋白质表观消化率的影响

试验选取20头中国荷斯坦奶牛随机分成3组,分别饲喂混合精料+青贮和精粗配合颗粒饲料+青贮日粮以研究精粗配合颗粒饲料对日粮粗蛋白、中性洗涤纤维、酸性洗涤纤维表观消化率的影响。结果表明:奶牛饲喂对照组、混合精料组和精粗配合颗粒饲料组日粮的NDF表观消化率分别为52.85%、47.62%、51.55%,相应ADF表观消化率47.28%、36.54%、49.58%,加工制粒后对纤维性物质表观消化率无显著影响(P>0.05);3组之间粗蛋白质表观消化率为71.72%、71.89%、70.23%(P>0.05)。

玉米秸秆精粗颗粒饲料生产与饲用研究

玉米秸秆与精料混合制成玉米秸秆精粗颗粒后密度增加,便于储存运输。玉米秸秆精粗颗粒饲料对奶牛日粮中粗蛋白质和纤维性物质的表观消化率无明显的影响,可提高奶牛饲料采食量。

Effect of Concentrate to Roughage Ratio on Cost Effective Growth Performance of Brahman Crossbred Calves

An experiment was conducted to evaluate the growth performance and cost per gain of Brahman × local crossbred bull calves receiving three diets with varying concentrate to roughage ratio （C：R） of 75：25, 65：35 and 55：45 on dry matter （DM） basis. Twelve bull calves （aging 11.5 ±1.2 months and 170.8 ± 13.0 kg live weight） divided into three equal groups were fed on three diets. The diets were balanced to 14.5% crude protein （CP） level and 10.5 MJ metabolizable energy （ME） per kg DM, formulating different concentrate mixtures. German grass （Echinoclora grousgali） and paddy straw were offered at 2：1 ratio on DM basis as roughages. The results revealed that C：R ratio did not affect （P 〉 0.05） the intake of feed and nutrients, feed efficiency （7.04, 6.94 and 6.76） and average daily gain （981,958 and 976 g）. Digestibility of nutrients was not affected （P 〉 0.05） by C：R. Animals fed diet with C：R = 55：45 had the lowest feed cost （Bangladeshi Taka 136.8 BDT/kg live weight gain）, which was increased （147.5 B DT and 153.8 BDT） non-significantly （P 〉 0.05） with the increasing level of concentrate. The diet consisting of 55% concentrate mixture showed similar results with the diet consisting of 75% concentrate mixture, but was comparatively economic. Therefore, considering the growth performance and cost per kg gain of Brahman crossbred growing calves, it may be concluded that the diet consisting of 55：45 C：R may be used for economic beef production.