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221.
电子报税是我国税制改革的一个重要组成部分,根据电子报税的具体要求确定了系统的功能模块、开发及运行平台和网络拓扑结构,并按照系统工程原则,用现代软件技术设计了纳税申报电子信息采集系统。 相似文献
222.
为研究青贮笋壳在奶牛生产中的应用效果,试验选用15头健康荷斯坦奶牛随机分成3组,即对照组、试验1组(6 kg青贮笋壳替代对照组日粮中1.5 kg的苜蓿干草)和试验2组(9 kg青贮笋壳替代对照组日粮中2.5 kg的苜蓿干草),进行为期60 d的饲养试验,其中预饲期10 d,正式期50 d。试验结果表明,试验1组产奶量较对照组和试验2组有所提高,但差异不显著(P>0.05),试验1组4%标准奶产量则显著高于试验2组和对照组(P<0.05)。试验1组乳脂率显著高于试验2组和对照组(P<0.05),其他乳成分含量各试验组均较对照组有所改善(P>0.05)。奶牛各项血清生化指标试验组和对照组间无显著差异,均处于正常生理范围。因此,青贮笋壳可以替代部分苜蓿干草在奶牛日粮中使用。 相似文献
223.
224.
《农业图书情报学刊》2012,24(1)
通过调查统计分析多校区多学科动态变化对图书馆馆藏文献配置典藏工作带来的影响,结合山东农业大学图书馆实际工作情况,提出了动态环境下文献配置典藏策略。 相似文献
225.
8头泌乳中期的奶牛被随机分为2组,分别是对照组(每头牛:基础日粮+棕榈酸钙200g/d)和试验组(每头牛:基础日粮+共轭亚油酸钙200g/d),试验期14d,检测了奶产量、乳成分,分析奶牛的血液变化,并采用荧光定量PCR对乳汁体细胞中脂蛋白脂酶(LPL)、乙酰辅酶A羧化酶(ACACA)的基因表达进行检测。结果显示,与对照组相比,试验组奶牛的乳产量、乳蛋白、乳糖和乳汁体细胞含量没有显著影响,但是显著降低了乳脂肪含量(P〈0.05),对照组和试验组奶牛乳脂肪含量分别为0.0326g/mL和0.0244g/mL。检测血液指标发现,共轭亚油酸钙显著升高了奶牛血液中高密度脂蛋白的含量(P〈0.05)。基因分析发现,试验组奶牛乳汁体细胞中LPL、ACA—CA的基因表达显著下调,表明共轭亚油酸钙抑制了奶牛乳腺细胞脂肪酸合成酶的基因表达。 相似文献
226.
李桂芬 《农业图书情报学刊》2021,33(12):89-98
[目的/意义]专题图书馆建设是图书馆事业发展的产物,也是图书馆事业创新的内容,近年来越来越多的专题图书馆纷纷建成,文章通过专题图书馆实证研究,旨在为国内高校图书馆专题图书馆建设提供借鉴。[方法/过程]利用文献调研法、典型案例分析法,在分析国内专题图书馆建设现状的基础上,以深圳大学城图书馆法律研究中心为例,解读其建设背景、实践及特点。[结果/结论]专题图书馆建设有助于促进高校图书馆形成资源及服务的核心竞争力。在专题图书馆建设中,高校图书馆需积极寻求契机,确定主题,注重与外力合作建设,加强宣传引导,构建立体化服务体系。 相似文献
227.
To eliminate unnecessary feeding trials, a mechanistic model of sugarcane digestion was used in the search for suitable supplements to improve milk production. Milk production simulated by the model was compared with data observed in four feeding trials published in the tropical literature where crossbred dairy cows were fed sugarcane/urea diets with different types of supplements. The predicted effects of the supplements on the ruminal microbial population, concentrations of ammonia and volatile fatty acids were also compared with the published results in one experiment. The model indicated the nutrient most limiting milk production for the different feeding situations. The addtion of Leucaena to the basal sugarcane/urea improved the availability of amino acids and long-chain fatty acids, with energy becoming the limiting factor. Supplementation with rice bran increased the availability of energy and long-chain fatty acids, but amino acids then became the limiting factor. Supplementation with both Leucaena and rice bran further improved the milk yield, but availability of energy now limited milk production. Supplementation with Leucaena increased milk production more than supplementation with king grass. The main reason for this increase was increased amino acid absorption due to increased microbial outflow. In all feeding situations, the average difference between the predicted milk production and that observed experimentally was 0.57 kg/d (ranging from 0.08 to 1 kg/d). 相似文献
228.
James T Rothwell Thomas J Burnett Kristina Hacket Roderick Chevis L Barry Lowe 《Pest management science》2001,57(11):993-999
The depletion of zeta‐cypermethrin residues in bovine tissues and milk was studied. Beef cattle were treated three times at 3‐week intervals with 1 ml 10 kg?1 body weight of a 25 g litre?1 or 50 g litre?1 pour‐on formulation (2.5 and 5.0 mg zeta‐cypermethrin kg?1 body weight) or 100 mg kg?1 spray to simulate a likely worst‐case treatment regime. Friesian and Jersey dairy cows were treated once with 2.5 mg zeta‐cypermethrin kg?1 in a pour‐on formulation. Muscle, liver and kidney residue concentrations were generally less than the limit of detection (LOD = 0.01 mg kg?1). Residues in renal‐fat and back‐fat samples from animals treated with 2.5 mg kg?1 all exceeded the limit of quantitation (LOQ = 0.05 mg kg?1), peaking at 10 days after treatment. Only two of five kidney fat samples were above the LOQ after 34 days, but none of the back‐fat samples exceeded the LOQ at 28 days after treatment. Following spray treatments, fat residues were detectable in some animals but were below the LOQ at all sampling intervals. Zeta‐cypermethrin was quantifiable (LOQ = 0.01 mg kg?1) in only one whole‐milk sample from the Friesian cows (0.015 mg kg?1, 2 days after treatment). In whole milk from Jersey cows, the mean concentration of zeta‐cypermethrin peaked 1 day after treatment, at 0.015 mg kg?1, and the highest individual sample concentration was 0.025 mg kg?1 at 3 days after treatment. Residues in milk were not quantifiable beginning 4 days after treatment. The mean concentrations of zeta‐cypermethrin in milk fat from Friesian and Jersey cows peaked two days after treatment at 0.197 mg kg?1 and 0.377 mg kg?1, respectively, and the highest individual sample concentrations were 2 days after treatment at 0.47 mg kg?1 and 0.98 mg kg?1, respectively. © 2001 Society of Chemical Industry 相似文献
229.
OBJECTIVE: To determine the changes in Ca, P, Mg, Na, K, S, Cu, Fe and Zn concentrations of milk during the lactation in pasture-fed Thoroughbred mares and then calculate the dietary mineral requirements of the sucking foal and the lactating mare. PROCEDURE: Milk was sampled on days 1, 3, 7, 14, 21, 28 and at various times between 55 to 65, 85 to 95 and 135 to 150 days after parturition from 21 pasture-fed mares. The concentrations of macro- and micro-elements in the milk were determined by inductively coupled plasma emission spectrometry. RESULTS: Concentrations (mg/L) of these elements were highest in colostrum (Mg 302, Na 561, K 955, S 1035, Cu 0.76, Fe 0.79 and Zn 5.5) except for Ca (1245) and P (895), which where highest on day 7. The mean milk mineral element concentrations (mg/L) over days 55 to 150 were Ca 843, P 543, Mg 47, Na 120, K 590, S 219, Cu 0.19, Fe 0.34 and Zn 2.1. The mean plasma element concentrations (mg/L) over the same period were Ca 120, P 77.1, Mg 17.0, Na 3110, K 168, S 983, Cu 1.1, Fe 1.5 and Zn 0.49. Concentration gradients between plasma and milk were observed and, in the case of Ca, P, Mg, K and Zn, their concentrations in milk were greater than those in plasma, while a reverse situation was observed for Na, S, Cu and Fe. CONCLUSION: With the exception of Ca and P, the highest concentrations of mineral elements were observed in the colostrum. The nursing foal should have access to good pasture or creep feed, because the intakes of Ca, P and Cu from milk may be less than optimum to meet the daily mineral element requirements. 相似文献
230.
Twenty each of healthy lactating Friesian and Holstein cows were studied. They were of similar age and body weight, nonpregnant in their third lactation and 80–100 days post partum. The investigation was carried out for 8 weeks on two farms at the same time during the hot summer season in Egypt. The first farm was in Demietta (North east of the Nile Delta, 31° 40 N) on 20 Friesian cows and the second was in Fakous (East of the Nile Delta, 30° 40 N) on 20 Holstein cows. On each of the two farms, 10 cows were newly imported and 10 were born in Egypt.The average daily milk yield and total milk production in the third lactation of the newly imported cows were significantly higher than those of the locally born cows for both Friesians and Holsteins. At the same time, the T4, T3, urea-N, haematological values and AST enzyme activity in the newly imported cows were significantly lower than those in the locally born ones in both breeds, while the locally born cows showed significantly lower values for rectal temperature and respiration rate, as well as for AST and Alk-P enzyme activities, than the newly imported cows of either breed.Holstein cows surpassed the Friesians in milk production, as well as thyroid hormone secretion and cholesterol, haemoglobin, packed cell volume and erythrocyte count values. The opposite was found for serum total protein, urea-N and creatinine concentrations, leukocyte count and AST, ALT and Alk-P enzyme activities. 相似文献