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991.
992.
[目的]探究生物炭施用量对土壤改良及烟叶发育的影响。[方法]以云烟87为试验材料,生物炭施用量设4个水平:CK(0)、T1(2 250 kg/hm2)、T2(4 500 kg/hm2)、T3(6 750 kg/hm2),研究不同稻秆生物炭施用量对土壤养分及烟叶的作用效果。[结果]生物炭在前期增加烟叶还原糖、总糖、淀粉含量而后期则降低其含量。对于总氮及氯的影响较小,尼古丁则呈降低态势。使烟叶化学成分更加协调,从而提高吸食品质。土壤生物炭能增加有机质含量,提高p H值,增加速效钾含量,减少速效磷含量,碱解氮则呈现先增加后减少。综合土壤养分与烟叶品质结果,施用生物炭4 500 kg/hm2处理组效果最佳。[结论]该研究可为生物炭的合理施用提供参考。 相似文献
993.
野生与船养瓦氏黄颡鱼肌肉营养组成与评价 总被引:1,自引:0,他引:1
[目的]比较野生和船体网箱养殖(船养)瓦氏黄颡鱼的肌肉营养组成。[方法]对采自同一水域的野生和船养瓦氏黄颡鱼的肌肉营养成分进行了比较。[结果]野生瓦氏黄颡鱼粗蛋白、粗灰分和粗脂肪含量分别为船养瓦氏黄颡鱼的1.16倍、1.69倍和0.90倍。在检测到的17种氨基酸中,野生瓦氏黄颡鱼除酪氨酸和组氨酸含量低于船养瓦氏黄颡鱼外,其余种类氨基酸均高于船养瓦氏黄颡鱼。野生瓦氏黄颡鱼总氨基酸(TAA)、总必需氨基酸(TEAA)、总鲜味氨基酸(TDAA)含量分别是船养瓦氏黄颡鱼的1.18倍、1.51倍和1.13倍。野生瓦氏黄颡鱼必需氨基酸构成比例符合世界粮农组织/世界卫生组织对优质蛋白质的要求,而船养瓦氏黄颡鱼不符合。根据氨基酸评分,野生瓦氏黄颡鱼的第一限制性氨基酸为缬氨酸,除缬氨酸外,其余必需氨基酸的氨基酸评分均大于等于0.90;船养瓦氏黄颡鱼的第一限制性氨基酸为亮氨酸,只有苯丙氨酸+络氨酸的氨基酸评分大于1,3种必需氨基酸的氨基酸评分在0.65以下;野生瓦氏黄颡鱼的必需氨基酸指数为69.62,船养瓦氏黄颡鱼为55.36。[结论]野生和船养瓦氏黄颡鱼的肌肉营养成分存在差异。野生与船养瓦氏黄颡鱼生活在同一水域,水质条件几乎一致,饵料差异可能是影响瓦氏黄颡鱼肌肉营养成分的主要原因。 相似文献
994.
995.
996.
胡枝子属植物研究进展 总被引:2,自引:0,他引:2
概述胡枝子属(Lespedeza Michx.)植物在中国民间药用情况、化学成分、药理作用等方面的研究进展。查阅近年来国内外的有关文献资料,并进行整理和归纳。胡枝子属植物在中国应用广泛,供药用的约有15种,主要含有黄酮、萜类、生物碱类化学成分;多具有抗炎、抗过敏、抗早孕、镇痛等药理活性。中国胡枝子属植物资源丰富,其药用价值值得关注,尤其是它对肾功能的作用,应以药理实验为指导,对其活性成分进行追踪研究,进而开发出安全有效的治疗肾功能不全的天然药物。 相似文献
997.
Identification of leptin gene polymorphisms associated with carcass traits and fatty acid composition in Japanese Black cattle 下载免费PDF全文
Fuki Kawaguchi Kazuki Okura Kenji Oyama Hideyuki Mannen Shinji Sasazaki 《Animal Science Journal》2017,88(3):433-438
Previous studies have indicated that some leptin gene polymorphisms were associated with economically important traits in cattle breeds. However, polymorphisms in the leptin gene have not been reported thus far in Japanese Black cattle. Here, we aimed to identify the leptin gene polymorphisms which are associated with carcass traits and fatty acid composition in Japanese Black cattle. We sequenced the full‐length coding sequence of leptin gene for eight Japanese Black cattle. Sequence comparison revealed eight single nucleotide polymorphisms (SNPs). Three of these were predicted to cause amino acid substitutions: Y7F, R25C and A80V. Then, we genotyped these SNPs in two populations (JB1 with 560 animals and JB2 with 450 animals) and investigated the effects on the traits. Y7F in JB1 and A80V in JB2 were excluded from statistical analysis because the minor allele frequencies were low (< 0.1). Association analysis revealed that Y7F had a significant effect on the dressed carcass weight in JB2; R25C had a significant effect on C18:0 and C14:1 in JB1 and JB2, respectively; and A80V had a significant effect on C16:0, C16:1, C18:1, monounsaturated fatty acid and saturated fatty acid in JB1. The results suggested that these SNPs could be used as an effective marker for the improvement of Japanese Black cattle. 相似文献
998.
This experiment was conducted to investigate the effect of feeding phytoestrogens on milk composition, blood biochemical index and antioxidant capacity of dairy cows.A total of 40 Holstein cows were selected and randomly divided into 4 groups by health, age and lactation stage. The cows in control group was fed total mixed rations(TMR), and the other in 3 trial groups were fed TMR supplemented with 2.5 g dainzein(group Ⅰ), 35 g formononetin (group Ⅱ), 1.25 g dainzein and 17.5 g formononetin (group Ⅲ), respectively. The total duration of the trial was 127 d, the first 7 d of the trial was the preliminary period and the formal trial lasted for 120 d. The milk samples were collected in the trial of 0, 30, 60, 90, 120 d, respectively, and determination of milk composition. The blood samples were collected by jugular vein in the trial, and plasma was separated by 15 min, 3 500 r/min centrifugation, and saved at -20 ℃ for later use. The result showed as follows: Compared with the control group, the milk yield and milk protein yield in groups Ⅰ and Ⅲ were significantly increased (P< 0.05),the lactose yield in groups Ⅰ,Ⅱ and Ⅲ were significantly increased (P< 0.05), the T-AOC activity of blood in group Ⅲ was significantly increased (P< 0.05), the GSH-Px activity of blood in groups Ⅱ and Ⅲ were significantly increased (P< 0.05), the MDA activity of blood in groups Ⅰ and Ⅱ were significantly decreased (P< 0.05), the milk fat yield,lactose rate and TP, ALB, GLB of blood were not significantly increased (P> 0.05),the CAT, SOD activity of blood in trail groups had a upward trent. It was concluded that feeding phytoestrogens could enhance the milk yield, milk protein yield, lactose yield, the body's antioxidant capacity and immune function of Holstein cows. 相似文献
999.
Domestic alfalfa supply has the obvious price advantage in the local dairy farms,but its feasible amount of feeding and the effect on the quality of fresh milk are still unclear for a lack of scientific experimental evidence. The alfalfa growed in Daqing city, Heilongjiang province was used in the present study,and one-year feeding experiment was performed to analyze the effect of alfalfa on the quality of fresh milk in the local 9 large-scale dairy farms. The results showed that compared with control group,the nutrient of fresh milk were not significantly improred when the amout of alfalfa was 3 kg/d (P >0.05).While the cude protein and dry matter of fresh milk were significantly increased (P <0.05) when the amount of alfalfa addition in the diet was 6 kg/d, but the milk fat and lactose percentage were not significantly affected (P <0.05). Moreover,the alfalfa addition in diet resulted in a significantly increase of unsaturated fatty acid percentage (P <0.05) and optimization of fatty acid composition of the fresh milk. In conclusion,it was helpful to improve the nutritional quality of fresh milk by changing the alfalfa amount of 3 kg/d,which was commonly used at present in dairy farms,to be 6 kg/d. 相似文献
1000.
试验旨在研究日粮中添喂两种植物雌激素及其组合物对奶牛乳成分、血液生化指标和抗氧化性能的影响。选取健康、年龄及泌乳期相近的40头荷斯坦奶牛,随机分为4组:1个对照组、3个试验组,每组10头。对照组饲喂全混合日粮,试验组在饲喂全混合日粮的基础上添加2.5 g大豆黄酮(试验Ⅰ组)、35 g芒柄花素(试验Ⅱ组)、1.25 g大豆黄酮和17.5 g芒柄花素(试验Ⅲ组)。预试期7 d,正试期120 d。分别于试验的第0、30、60、90、120天采集乳样,测定乳成分;颈静脉采集血液样品,3 500 r/min离心15 min,分离血浆,-20 ℃保存备用。结果表明,与对照组相比,试验Ⅰ、Ⅲ组产奶量、乳蛋白产量均显著提高(P< 0.05);试验Ⅰ、Ⅱ、Ⅲ组乳糖产量显著提高(P< 0.05);试验Ⅲ组T-AOC显著提高(P< 0.05);试验Ⅱ、Ⅲ组GSH-Px活性显著提高(P< 0.05);试验Ⅰ、Ⅱ组MDA含量极显著降低(P< 0.05);乳脂产量、乳糖率及TP、ALB、GLB含量均无显著差异(P> 0.05);CAT、SOD活性均有一定程度的提高。由此可见,日粮中添喂两种植物雌激素及其组合物能够在一定程度上提高荷斯坦奶牛的产奶量、乳蛋白含量和乳糖含量,能够提高奶牛机体抗氧化能力,增强免疫功能。 相似文献