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51.
菠萝皮发醇生产饲料蛋白的工艺条件研究 总被引:1,自引:0,他引:1
菠萝皮是菠萝加工产生的副产物,为了将菠萝加工企业废弃的菠萝皮有效利用,实现资源的再生,缓解目前蛋白饲料的不足,进行了本研究.结果表明,采用绿色木霉和产朊假丝酵母混合菌种发酵,添加麸皮20%、硫酸铵3%、尿素2%,料水比11,自然pH值,30℃发酵5 d,发酵后的饲料粗蛋白含量提高到25.38%,经水洗后的粗蛋白含量提高到17.03%,检测的16种氨基酸含量均有很大幅度的提高,其总和从2.89%提高到15.6%,提高率达到439.8%.产品气味芳香,适口性大为改善,可用做牛、羊和鱼等养殖的低蛋白能量饲料. 相似文献
52.
甲酸钙的合成、测定及其在乳猪料中的应用 总被引:2,自引:0,他引:2
甲酸钙作为一种饲料添加剂,能降低和调节胃肠道pH值、促进营养物质的消化和吸收。本文系统介绍了甲酸钙的合成和检测方法,并介绍了甲酸钙作为饲料添加剂的作用效果。 相似文献
53.
维生素E调控肉品质的研究进展 总被引:1,自引:0,他引:1
猪肉的品质受很多因素的影响,其中起主导作用的是猪的品种,例如:杜洛克、皮特兰等猪的肉质差别很大。然而,现在越来越多的动物营养学家认识到日粮的组成对肉质也有很重要的影响,尤其是添加维生素E的日粮。维生素E是有效的抗氧化剂,能够抑制肌肉组织中脂肪的氧化。饲粮中添加维生素E能够减少脂肪的氧化(酸败速度下降)和水分的损失(烹任前和烹任过程中水分的损失),同时改善肉的颜色和风味。提高保质期。 相似文献
54.
20世纪初,美国首先将净能体系应用于奶牛的日粮配制当中,但该体系一度被认为并不适用于单胃动物,特别是猪的日粮配制。因为对猪而言,消化能体系更为方便和适用。但时下,通过添加合成氨基酸的低蛋白日粮的成功研究和利用,使消化能体系变得过时。在欧洲,净能体系已经被用于猪日粮 相似文献
55.
在(25±1)℃水温、自然光照条件下,设3种投喂方式饲养革胡子鲶(clarias leath-er):第1种连续投喂整个试验期间不间断,第2和3种分别连续投喂3、7 d 后饥饿1 d,3种方式分别以R0(对照组)、R1/3、R1/7表示,试验周期共45 d。结果显示:R0、R1/3和R1/7组胃、后肠和肝脏中蛋白酶活性影响差异不显著,但前肠和中肠内蛋白酶活性影响存在差异(P<0.05)。R0、R1/3、R1/7组的胃、前肠、中肠、后肠和肝脏中淀粉酶影响不显著,R0、R1/3、R1/7的胃、前肠和肝脏内脂肪酶活性影响差异显著(P<0.05),而R0、R1/3、R1/7组中肠和后肠中脂肪酶活性影响差异不显著(P>0.05)。 相似文献
56.
57.
An experiment was carried out to investigate the variability in apparent ileal amino acid (AA) digestibilities in simulated samples of wheat shorts consisting of different proportions of wheat bran (WB), wheat shorts (WS), and wheat flour (WF), hereafter referred to as wheat fractions. The proportions of WS, WB, and WF and the NDF content (DM basis) of the wheat fractions were as follows: A, 70% WS, 30% WB, and 42.3% NDF; B, 85% WS, 15% WB, and 41.8% NDF; C, 100% WS and 41.3% NDF; D, 85% WS, 15% WF, and 35.2% NDF; and E, 70% WS, 30% WF, and 29.5% NDF. Six barrows, average initial BW of 37.2 kg, fitted with a simple T-cannula at the distal ileum, were fed one of six experimental diets according to a 6 x 6 Latin square design. Six diets were formulated to contain 17% CP (as-fed basis). Diets A, B, C, D, and E contained 17.53% soybean meal (SBM), which contributed 50% of the CP in these diets. The wheat fractions contributed the remaining 50% of the CP in these diets. Diet F contained 35.05% SBM, which was the sole source of dietary CP. Chromic oxide was used as the digestibility marker. During the first experimental period, the daily dietary allowance was provided at a rate of 5% (wt/wt) of the average BW. Thereafter, the daily dietary allowance was increased by 100 g at each successive period. Each experimental period comprised 12 d. Following a 7-d adaptation period, feces were collected for 48 h and ileal digesta for a total of 24 h. The apparent ileal digestibilities of AA in the wheat fractions were calculated using the difference method. The digestibilities were usually lowest in the wheat fractions containing WB and highest in those containing no WB. The average of the digestibilities of the indispensable AA was 63.5% for wheat fraction A, which contained 30% WB, and 71.9% for wheat fraction C, which did not contain WB. There were no differences (P > .05) in lysine digestibilities among the wheat fractions, which ranged from 54.7 to 64.1%. Of the indispensable AA, with the exception of arginine, lysine, and methionine, the apparent ileal digestibility values of AA were negatively correlated (P < .05) with the NDF content in the wheat fractions. 相似文献
58.
This study was conducted to investigate the effects of Bacillus subtilis B10 spores on the viability and biological functions of murine macrophage. RAW 264.7 cells were stimulated both with and without B. subtilis B10 spores for 12 h. Then cell viability was determined to evaluate the cytotoxic effect of B. subtilis B10 spores to the cells, and the activities of acid phosphatase (ACP) and lactate dehydrogenase (LDH), the production of nitric oxide (NO) and inducible nitric oxide synthase (iNOS), and the secretion of inflammatory cytokines were measured to analyze the functions of macrophages. The results showed that B. subtilis B10 spores were not harmful to RAW 264.7 cells and they also strongly enhanced the activities of ACP and LDH (P < 0.01), remarkably increased NO and iNOS production (P < 0.01), and significantly stimulated the secretion of pro‐inflammatory cytokines, including tumor necrosis factor‐alpha (TNF‐α), interferon‐gamma (IFN‐γ), interleukin‐1 beta (IL‐1β), IL‐6, IL‐8 and IL‐12 (P < 0.01) while they reduced anti‐inflammatory cytokine IL‐10 (P < 0.01). The outcomes suggest that B. subtilis B10 spores are not only safe for murine macrophages, but also can activate these cells and enhance their immune function. The above findings suggest that B. subtilis B10 spores are potentially probiotic. 相似文献
59.
昆虫唾腺是昆虫消化系统中重要的器官,不同的昆虫唾腺形态各异,功能也有差别;完全变态昆虫幼虫的唾腺由胚胎皮细胞内陷而成,成虫唾腺由成虫唾腺芽发育而成,幼虫的唾腺在昆虫变态发育过程中会发生退化、消亡,其为程序性细胞死亡过程。本文对昆虫唾液腺的形态、功能及其在变态发育过程中发生程序性细胞死亡的情况进行概述。 相似文献
60.
自20世纪70年代出现蜂蜜掺假现象,这与高果糖玉米糖浆(HFCS)的工业发展相吻合。HFCS可从各种植物原料(如小麦、甜菜、甘蔗)获得的异构 相似文献