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101.
通过对福建省惠安县不同林龄短枝木麻黄人工林不同发育阶段小枝单宁含量及氮磷再吸收率的研究,探讨了短枝木麻黄林分发育过程中的营养保存策略。结果表明,幼龄林(5年生)成熟小枝中的总酚(TP)、可溶性缩合单宁(ECT)总缩合单宁(TCT)含量及蛋白质结合能力(PPC)显著高于成熟林(21年生)和衰老林(38年生)。随着林分发育,成熟小枝中N含量显著升高,而P含量呈降低趋势。不同发育阶段林分成熟小枝中N:P比均大于20,且随着林龄的增加而升高。磷再吸收率(PRE)显著高于氮再吸收率(NRE),均以成熟林分最高。这表明短枝木麻黄小枝单宁含量与养分再吸收受林龄影响,其养分保存机制会随着林分生长发育的变化而进行调节。 相似文献
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The effect of canola meal tannins on the intestinal absorption capacity of broilers using a D‐xylose test 下载免费PDF全文
B. Mansoori A. Rogiewicz B. A. Slominski 《Journal of animal physiology and animal nutrition》2015,99(6):1084-1093
In three D‐xylose absorption experiments, the effect of 1% HCl/methanol, 70% methanol or 70% acetone extracts of canola meal (CM) or 70% acetone extract of soybean meal (SBM) containing polyphenols, phenolic acids, tannins and phytic acid on intestinal absorption capacity of broilers was determined. In Exp. 1, the experimental groups received orally D‐xylose solution alone or with methanol/HCl, methanol or acetone extracts of CM. In Exp. 2, the experimental groups received D‐xylose alone or with acetone extracts of CM or SBM. In Exp. 3, the experimental groups received D‐xylose plus sucrose solution or D‐xylose plus acetone extracts of CM or SBM. In Exps. 2 and 3, the CM extracts contained 2.7 and 2.6, 2.4 and 2.3, 3.2 and 3.2, and 2.4 and 2.2 times higher polyphenols, phenolic acids, tannins and condensed tannins than the corresponding SBM extracts respectively. Blood samples were collected in 40‐min intervals, and plasma D‐xylose was measured. Compared to the Control, plasma D‐xylose in Exp. 1 was lower (p < 0.001) by 81, 69 and 73% at 40‐min, by 41, 44 and 37% at 80‐min and by 22, 31, and 23% at 120‐min post‐ingestion of the HCl/methanol, methanol and acetone extracts respectively. In both Exps. 2 and 3, plasma D‐xylose level was lower (p < 0.001) in groups dosed with CM extract or SBM extract at each time of blood collection, when compared to the respective Control group. However, in Exp. 3, birds dosed with SBM extract had higher plasma D‐xylose than CM extract‐dosed birds by 28, 8 and 21% at 40, 80 and 120 min respectively (p < 0.01). In conclusion, although CM extract caused a lower absorption of D‐xylose, based on 5 to 10% of CM inclusion levels in practical broiler rations, the soluble bioactive components of CM will likely have minor impact on the absorption capacity of the chicken intestine. 相似文献
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Studies were conducted to compare the effects of using two microbial inoculants, a sulphite salt‐based additive, formic acid and quebracho tannins, on the fermentation quality, nutritive value and aerobic stability of pea/wheat bi‐crop silages. Spring peas (Pisum sativum var. Magnus) and spring wheat (Triticum aestivum var. Axona) were drilled together at rates that gave high (HP/W; 3:1) or low (LP/W; 1:3) pea to wheat ratios. The peas and wheat were harvested at the yellow wrinkled pods and late milk/early dough maturity stage, respectively, and conserved in 1·5‐kg polyethylene bag, laboratory silos. The bi‐crops were conserved without treatment (control) or treated with either of two lactic acid bacteria‐based inoculants [Lactobacillus buchneri; applied at 105 colony‐forming units (CFU) g–1 fresh weight (FW) or Lactobacillus plantarum (applied at 106 CFU g–1 FW)], sulphite salts (applied at the rate of 1 ml sulphite solution kg–1 FW), quebracho tannins (applied at 16 g kg–1 FW) and formic acid (applied at 2·5 g kg–1 FW). Six replicates were made for each treatment, and the silos were opened after 112 days of ensilage. The level of peas in the bi‐crop influenced the effectiveness of the additives. With the exception of sulphite salts, all the additives significantly reduced the soluble nitrogen (N) and ammonia‐N concentrations of all the silages. The ratio of lactic acid to acetic acid was generally lower in the LP/W silages than in the HP/W silages, and the additive treatments only increased the in vitro digestible organic matter in dry matter of the LP/W silages. Of all the additives evaluated, formic acid resulted in the least aerobic spoilage in HP/W bi‐crop silages. However, in the LP/W bi‐crops, additive treatment was not necessary for ensuring aerobic stability. 相似文献
107.
阳离子单宁-聚铝复合絮凝剂处理高有机物含量废水的研究 总被引:9,自引:0,他引:9
37%甲醛溶液40mL,33%二甲胺水溶液80mL,室温下反应1.5h得预反应液。落叶松栲胶54.7g,60℃下与预反应液100mL反应2.5h,骤冷至室温,用氯化铵和盐酸的混合溶液调反应液pn值至4.5~5.0,继续反应1h。所得产物(CAT)与聚合氯化铝(PAC)混合反应得到复合絮凝剂,最佳反应条件为:CAT:PAC为1:4(质量比),反应温度30℃,反应时间1h。所得复合絮凝剂适用于室温下处理酸性高有机物含量废水,絮凝剂投加量100mg/L。可过滤态CODcr去除率可达60%以上,色度去除率70%以上,浊度去除率80%以上。 相似文献
108.
Lamy E da Costa G Santos R Capela e Silva F Potes J Pereira A Coelho AV Baptista ES 《Journal of animal physiology and animal nutrition》2011,95(3):304-312
Saliva appears as a defence mechanism, against potential negative effects of tannins, in some species of animals which have to deal with these plant secondary metabolites in their regular diets. This study was carried out to investigate changes in parotid saliva protein profiles of sheep (Ovis aries) and goats (Capra hircus), induced by condensed tannin ingestion. Five Merino sheep and five Serpentina goats were maintained on a quebracho tannin enriched diet for 10 days. Saliva was collected through catheters inserted on parotid ducts and salivary proteins were separated by two-dimensional gel electrophoresis. Matrix-assisted Laser desorption ionization - time of flight (MALDI-TOF) and liquid chromatography tandem mass spectrometry (LC-MS/MS) were used to identify the proteins whose expression levels changed after tannin consumption. Although no new proteins appeared, quebracho tannin consumption increased saliva total protein concentration and produced changes in the proteome of both species. While some proteins were similarly altered in both species parotid salivary protein profile, sheep and goats also presented species-specific differences in response to tannin consumption. 相似文献
109.
为明确常用杀虫剂对棉花抗虫性的影响,研究了灭多威和吡虫啉营养液处理对棉苗中抗虫次生物质缩合单宁含量的影响。结果表明,25mg/L灭多威处理3叶期棉苗后第6、9、12和15天,50mg/L灭多威处理棉苗后第6天和第15天,棉叶中缩合单宁含量均显著增加,其中25mg/L灭多威处理棉苗15天,棉叶中缩合单宁的含量较对照增加74%。50mg/L吡虫啉处理棉苗后第2天,棉叶中缩合单宁含量与对照相比增加了45%,而吡虫啉的其它处理浓度和处理时间未对棉苗缩合单宁含量产生显著影响。杀虫剂对棉苗缩合单宁含量的影响与杀虫剂本身的性质密切相关,其中灭多威对棉苗缩合单宁含量影响较大,而吡虫啉影响则较小。此外,杀虫剂对棉苗缩合单宁含量的影响还具有一定的剂量效应与时间效应。 相似文献
110.
Bamikole MA Ikhatua UJ Arigbede OM Babayemi OJ Etela I 《Tropical animal health and production》2004,36(2):157-167
The suitability of five species of Ficus, F. mucoso, F. thonningii, F. polita, F. religiosa and F. benjamina, for feeding ruminant livestock was studied. The nutritive and antinutritive components were determined and the acceptability of the forages to livestock was assessed using a cafeteria method in 8 adult small ruminants. Also, the degradation potential of the dry matter of the five Ficus species was investigated using 3 fistulated sheep. The crude protein (CP) content of the Ficus species varied significantly (p < 0.05), ranging from 130 to 180 g/kg DM. The content of neutral detergent fibre (NDF) also varied significantly (p < 0.05), ranging from 650 to 710 g/kg DM. The organic matter (OM) contents did not differ significantly (p > 0.05), having a mean value of 916 g/kg DM. The concentrations of tannin, saponin, phytic acid and oxalic acid were low. The acceptability of the forage was similar for four of the species but poor for F. polita. The extent of DM degradation varied significant among the Ficus species, the ranking order being F. benjamina > F. thonningii > F. mucoso > F. religiosa > F. polita. 相似文献