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61.
试验以产朊假丝酵母(Candida utilis)为出发菌株,味精废水、玉米粉和麸皮为底物,固态发酵生产饲料酵母。通过感官性状、活菌数、水溶性蛋白、小肽及氨基酸的测定来评价不同味精废水添加量对固态发酵的影响。结果表明:味精废水添加10%时,发酵效果最佳。发酵后活菌数达8.02logCFU/g;水溶性蛋白和小肽含量分别为7.99%和5.42%;游离氨基酸含量为17.82%,较不添加味精废水组及添加20%组分别高出1.26和0.9个百分点(P<0.05)。味精废水作为廉价的非蛋白氮原料,可用于产朊假丝酵母固态发酵的生产中,具有很好的经济效益和开发潜力。 相似文献
62.
20世纪80年代以来世界除草剂新品种开发进展及特点(一) 总被引:2,自引:0,他引:2
综述了近20年来世界除草剂新品种的开发进展,并介绍了除草剂工业发展的一些新特点。 相似文献
63.
本文总结了多菌种组合微生物发酵降解剂处理粗饲料的固态发酵工艺,所用菌种的筛选及其优化组合,以及多菌种组合微生物发酵降解剂使用技术的创新,即作为以提高秸秆饲养效果为目标的营养工程技术的配套产品之一进行使用。 相似文献
64.
江滨 《四川畜牧兽医学院学报》2007,5(4):192-194
经济发展、社会进步、科技发达要依赖劳动者素质的提高,劳动者素质的提高要依赖素质教育,素质教育是全面提高公民思想道德、文化素养、身心素质等方面发展水平的教育。文中论述了素质教育的含义、结构、特征与实施方法。同时比较分析了素质教育与应试教育的区别,进一步明确了素质教育的特点和宗旨。 相似文献
65.
66.
办公环境是现代环境设计的一个重要组成部分,本文结合重庆高速公路集团有限公司办公楼环境设计分析,探讨在满足办公环境基本功能要求前提下对地域环境的尊重与回归,创造具有地域特征的个性化办,厶\环境。 相似文献
67.
Eight multiparous lactating Holstein cows were randomly assigned in a 4 × 4 replicated Latin square design to receive four dietary treatments. The dietary treatments were monosodium glutamate by‐product (MSGB) replacement for soybean meal in concentrate at four levels: MSGB replacement at 0, 20, 40 and 60%, respectively. Pangola hay was given on an ad libitum basis. It was found that total dry matter intake, concentrate intake, pangola hay intake and all apparent digestibilities were not different among treatments. Ammonia nitrogen concentration in the rumen at 4 h post‐feeding was significantly different, in which the 0% treatment had the highest (P < 0.05) while the 20% treatment had the lowest. Milk fat percentage was the highest (P < 0.05) in the 0% treatment. MSGB replacement at 40% and 60% were shown to be the lowest (P < 0.05) feed cost for milk production, and profitability of milk production was the highest (P < 0.05) for the 60% treatment. Based on this experiment, it could be concluded that MSGB replacement for soybean meal at 20‐60% in the feed for dairy cows presented no negative effects on their performances. In addition, it could decrease feed cost 2.9‐17.3% and increase milk production profit up to 33.3% in the 60% treatment. 相似文献
68.
Exogenous application of thiamine (vitamin B1) during imbibition improved germination and seedling development of bean (Phaseolus vulgaris L. cv. Lasso) seeds, which were exposed to soaking injury by submergence. Leaching of the vitamin into the incubation medium was not increased in submerged seeds. However, translocation of the thiamine reserves from the cotyledons to the seedling axis was reduced in response to soaking injury. After exogenous application of free thiamine to the seeds, thiaminedi-phosphate (TDP), which is the physiologically active coenzyme form of thiamine, accumulated in the seedling axis of submerged seeds, suggesting an increased demand for thiamine-dependent metabolic reactions in these tissues. Limited oxygen supply of the seeds during the soaking period induces a shift from respiration to fermentation of carbohydrates. Neither thiamine-dependent ethanolic fermentation, nor ATP production or adenylate energy charge (AEC) of the seedling axis were affected by exogenous thiamine application, suggesting that there is no limitation of thiamine-dependent reactions in the energy metabolism of the seedlings. Thus the physiological mechanisms improving germination and seedling development of submerged seeds in response to thiamine seed treatment are still not clear. 相似文献
69.
K. Gerlach F. Pfau M. Pries K. Hünting K. Weiß W. Richardt K.‐H. Südekum 《Grass and Forage Science》2018,73(3):599-609
Nine hybrids (three maturity groups, dry matter 343 ± 5.6 g/kg) of whole‐crop maize were ensiled in eight replicates in laboratory‐scale silos. Each hybrid was sampled at harvest and after 30, 60, 90 and 120 days (d) of ensiling. Samples were analysed for chemical composition (proximate constituents, fermentation products and pH), starch, non‐protein N (NPN) and NH3‐N. Each sample and its neutral detergent fibre (NDF) fraction were incubated in the Hohenheim gas test system. In vitro gas production was measured after 0, 2, 4, 8, 12, 16, 24, 36, 48, 72 and 96 hr of incubation. Gas production of the neutral detergent soluble (NDS) fraction (mainly starch) was calculated using a curve subtraction method. Gas production dynamics over time were estimated using a nonlinear regression equation; afterwards, a two‐factorial analysis of variance (storage length, maturity group and their interaction) using the general linear models procedure was conducted. After 30 d, all silages were well fermented. Most fermentation products and proximate constituents only changed until 30 or maximum 60 d of ensiling. Only few changes in in vitro nutrient degradability were detected after the first 30 d or as influenced by maturity group. Ensiling per se increased the ruminal degradability of the NDS, but there was no further increase caused by a prolonged duration of storage. However, extensive changes in crude protein fractions occurred with a linear increase in NPN and NH3‐N compounds from 0 to 120 d of storage, indicating continual protein and amino acid degradation. 相似文献
70.
The objective of this study was to investigate rumen available soluble, insoluble and total protein (CP), estimated structural (SC) and non‐structural carbohydrate (starch: ST), degradation characteristic ratios and hourly effective degradation of six barley varieties during three consecutive growth years (2003, 2004, 2005). The magnitude of the differences was determined between the varieties and growth years. Measured degradation kinetics included soluble fraction (S), undegradable fraction (U), lag time (T0) and rate of degradation (Kd) of the insoluble but degradable fraction (D). Rumen available soluble, insoluble, and total N, SC and ST and the rumen degradation characteristic ratios were determined using the Tamminga rumen degradation ratio system. Characteristics of the hourly effective degradation between N and carbohydrate (CHO) among the six barley varieties for 3 years were also studied. The degradation ratios included were total rumen available N and carbohydrate ratio (FN/FCHO), rumen available soluble N and carbohydrate ratio (SN/SCHO), and rumen available insoluble N and carbohydrate ratio (EN/ECHO). Results show that both the barley variety and growth year had a significant effect on degradation kinetics (S, D, U, T0 and/or Kd). Differences in the ratio of FN/FCHO among varieties ranged from 16.6 to 19.0 g/kg (p < 0.01). There was no difference in SN/SCHO (p > 0.05) with an average of 4.9 g/kg. The difference in the EN/ECHO ratio tended to be significant among the varieties (p = 0.069) ranging from 18.4 to 21.3 g/kg. Differences in the hourly effective degradation between N and CHO were relatively small at shorter incubation times (2–4 h) However, as the length of rumen incubation increased (12–24 h), much larger differences in the rate of effective hourly degradation were observed. In conclusion, both barley variety and growth year had significant effects on rumen degradation kinetics. The mean FN/FCHO ratio of 17.2 (16.6–19.0) was observed for the six barley varieties in this experiment. All barley varieties exhibited a less optimal rumen fermentation ratio (17.2 < optimum: FN/FCHO = 25 to 33 g N per kg CHO). The large differences in the degradation kinetics, characteristics ratios and hourly effective degradation among barley varieties and growth years may help to explain some of the large variations that are seen in cattle performance. 相似文献