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31.
Masahito SUGIMOTO Waka SAITO Motoki OOI Yukinobu SATO Toshiro SAITO Kiyokazu MORI 《Animal Science Journal》2006,77(6):587-594
Six ruminally cannulated Wagyu (Japanese Black) steers (average initial bodyweight (BW) 387 ± 29 kg) were used in a split‐plot design experiment, comprising a 3 × 3 Latin square design (whole plot) and a randomized block design (subplot). The whole plot treatments were three different feeding levels of supplemental diet, fed at 0.2, 0.4 and 0.6% of BW, on a dry matter (DM) basis. Subplot treatments were two different supplemental diets: a potato pulp silage‐based diet (PPS) and a grain‐based diet (GRAIN). Chopped, medium‐quality cool‐season grass hay (predominately Timothy, Phleum pratense L) was fed daily at 0.7% BW (on a DM basis) as the basal diet. Each period consisted of 21 d, which included 11 d of adaptation to the diets and 10 d of the collection period. Chromium oxide was used as an indigestible marker. In situ forage degradation was measured using the nylon bag technique. The dry matter intake increased (linear; P < 0.01) as the feeding level increased and was not affected by the diet. Digestibility was not affected by any treatments. The GRAIN diet tended to decrease the rate of in situ forage degradation as the feeding level increased, but this trend was not found in the steers fed the PPS diet. Steers fed the GRAIN diet had a lower (P < 0.1) ruminal pH compared with steers fed the PPS diet. Ruminal pH was not significantly affected by feeding level; however, it was numerically higher for steers supplemented at 0.2% per BW than that for the steers supplemented above 0.4% per BW due probably to the higher starch intake. The total volatile fatty acids concentration numerically increased as the feeding level increased and was not affected by the diet. Increasing the feeding level decreased (linear, P < 0.01) the proportion of acetate. Neither diet nor the feeding level had any effects on the proportion of ruminal propionate. The results suggested that, for steers fed the PPS diet, there are not adverse effects on forage digestion in the rumen that occur as the feeding level is increased. 相似文献
32.
研究以鲜牛奶、菠萝果肉为主要原料,通过正交实验,确定菠萝果肉酸奶生产最佳的工艺条件.结果表明:添加糖4%,菠萝果肉3%,琼脂0.05%,44 ℃条件下发酵3 h,获得的菠萝果肉酸奶品质最佳.另外,产品融合了酸奶和菠萝的风味,组织状态均匀,口感好,丰富了酸奶的品种. 相似文献
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以5个沙棘(Hippopha觕rhamnoides L.)品种的果实为试材,建立气相色谱内标法测定沙棘果肉油和种子油主要脂肪酸成分的方法。果肉油和种子油采用氯仿-甲醇法提取,甲醇钠-甲醇法甲酯化衍生后进行定性和定量。结果表明,十九烷酸甲酯是气相色谱法测定沙棘果实中脂肪酸成分含量的理想内标物。果肉油和种子油中的主要脂肪酸为棕榈酸、棕榈油酸、硬脂酸、油酸、亚油酸和α-亚麻酸。果肉油中棕榈油酸(36.25%)和棕榈油酸(28.92%)含量高,α-亚麻酸含量低;种子油中亚油酸(33.65%)和α-亚麻酸(32.95%)含量高,棕榈油酸含量低。5个品种沙棘的果肉油和种子油中主要脂肪酸的组成及含量存在一定的差异。亚历山大12号果肉油中的脂肪酸含量最高,为84.84 g/100 g油;无刺丰种子油中的脂肪酸含量最高,为88.39 g/100 g油。该方法操作简便、快速、重复性好,适合沙棘油脂样品中脂肪酸的定量测定。 相似文献
34.
Kraft pulp bleaching effluent supplemented with glucose was decolorized by a newly isolated fungusGeotrichum candidum Dec 1 (Dec 1) that showed a wide decolorizing spectrum to synthetic dyes. When the glucose concentration in the effluent was 30 g/l, the color removal and the reduction of absorbable organic halogens were 78% and 43% after 7 days culture, respectively. The average molecular weight of colored substances measured by gel filtration chromatography was lowered to less than 3000 from 5600 after 7 days culture. As the contribution of extracellular enzymes such as peroxidase (DyP), manganese peroxidase, and laccase to the decolorization of the kraft pulp bleaching effluent was small, Dec 1 appears to have a different mechanism of decolorizing kraft pulp bleaching effluent when compared with enzymes used to decolorize synthetic dyes. 相似文献
35.
本文根据国内外(包括中国、印度、日本、孟加拉国、缅甸、菲律宾、澳大利亚、苏联等)报道的竹材制浆造纸方面资料综合而成。文章内容有引言、竹材纤维形态与化学成分、世界竹材造纸工业简况和造纸竹材利用的经济效益。文章列举大量事实说明造纸工业用竹材为原料比用针叶材或阔叶材经济效益高。 相似文献
36.
This review covers both physical and chemical modifications of cellulose fibre surface and their impact on the properties of the ensuing papers. It is not restricted to actual industrial operations, but also deals instead with ongoing research in this area, which appears promising in terms of possible applications to papermaking. 相似文献
37.
为提高胡萝卜制浆的品质,以新鲜东方六寸参胡萝卜为原料,采用高效液相色谱法测定胡萝卜浆中β-胡萝卜素含量。比较了热水热烫、蒸汽热烫、维生素C热烫、柠檬酸热烫等4种不同的热烫方式对胡萝卜浆中β-胡萝卜素含量的影响,并用Box-Behnken响应面设计法优化热烫处理的工艺条件。结果表明,柠檬酸热烫为最佳热烫方式,优化得到的柠檬酸热烫工艺条件为:柠檬酸质量分数1.4%、热烫时间18min、热烫温度84℃。经验证在此条件下,β-胡萝卜素质量分数23.59mg/kg,与模型预测值吻合,建立的模型可用于工艺预测。因此,本研究结果可为改善胡萝卜制浆的品质提供技术依据。 相似文献
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