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1.
针对我国南方地区冬闲田数量多、利用率低的现象,充分利用冬闲田种草养畜,不仅可以解决牲畜季节性青绿粗饲料缺乏问题,还能促进农民增收和农业可持续发展。一年生黑麦草由于适生范围广,鲜草产量高,营养丰富且柔嫩多汁,适口性好,家畜家禽喜欢采食,深受农户青睐,成为一种极具发展前途的越年生优质牧草,近年来在畜牧业生产中得到广泛应用。本文从一年生黑麦草生物性状、营养特性、冬闲田的丰产栽培技术、青贮技术以及在各类畜禽的饲喂研究角度进行综述,并指出今后的研究重点和方向。旨在为一年生黑麦草在畜牧业中的进一步推广应用提供参考。 相似文献
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《中国油料作物学报(英文)》2021,6(4):159-163
The International Symposium on Lipid Science and Health (ISLSH), which was organized annually by Oil Crops Research Institute of Chinese Academy of Agricultural Sciences (OCRI-CAAS) since 2016, has gained a strong reputation and attracted hundreds of delegates from around the world for discussion of lipid research trends and advances every year, to promote research and academic exchanges in the fields of lipid science and health. The 5th International Symposium on lipid Science and Health was successfully held in Wuhan, China, from October 23rd to 25th, 2020, to celebrate the 60th anniversary of OCRI-CAAS. The two-day symposium gathered well-known experts specialized in lipid science to share the current state of lipid research with emphasis on aspects covering: (1) lipid profiling and characterization, (2) lipid preparation and modification, (3) lipid improvement and regulation, and (4) lipid nutrition and health. The symposium was conducted by a combination of on-site and network meeting. More than 250 distinguished delegates from academia and industry participated in the on-site multidisciplinary meeting, and thousands of scholars attended the virtual event. This paper is as a record of the symposium proceedings and a brief summary of the advances and trends in 4 aspects of lipid science and health. 相似文献
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Sheng-cai QIANG Fu-cang ZHANG Miles Dyck Yan ZHANG You-zhen XIANG Jun-liang FAN 《农业科学学报》2019,18(10):2369-2380
Excessive use of nitrogen(N) fertilizers in agricultural systems increases the cost of production and risk of environmental pollution. Therefore, determination of optimum N requirements for plant growth is necessary. Previous studies mostly established critical N dilution curves based on aboveground dry matter(DM) or leaf dry matter(LDM) and stem dry matter(SDM), to diagnose the N nutrition status of the whole plant. As these methods are time consuming, we investigated the more rapidly determined leaf area index(LAI) method to establish the critical nitrogen(N_c) dilution curve, and the curve was used to diagnose plant N status for winter wheat in Guanzhong Plain in Northwest China. Field experiments were conducted using four N fertilization levels(0, 105, 210 and 315 kg ha-1) applied to six wheat cultivars in the 2013–2014 and 2014–2015 growing seasons. LAI, DM, plant N concentration(PNC) and grain yield were determined. Data points from four cultivars were used for establishing the N_c curve and data points from the remaining two cultivars were used for validating the curve. The N_c dilution curve was validated for N-limiting and non-N-limiting growth conditions and there was good agreement between estimated and observed values. The N nutrition index(NNI) ranged from 0.41 to 1.25 and the accumulated plant N deficit(N_(and)) ranged from 60.38 to –17.92 kg ha~(-1) during the growing season. The relative grain yield was significantly affected by NNI and was adequately described with a parabolic function. The N_c curve based on LAI can be adopted as an alternative and more rapid approach to diagnose plant N status to support N fertilization decisions during the vegetative growth of winter wheat in Guanzhong Plain in Northwest China. 相似文献
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以鹰嘴豆蛋白为原料,建立复合酶分步酶解法制备鹰嘴豆短肽的工艺。在鹰嘴豆蛋白碱性蛋白酶Alcalase水解的基础上,进一步采用中性蛋白酶和风味蛋白酶Flavourzyme继续水解鹰嘴豆蛋白碱性蛋白酶Alcalase酶解物,并对各影响因素进行研究,建立短肽得率与各影响因素的回归模型,利用高效液相色谱法和氨基酸自动分析仪等测定鹰嘴豆短肽的相对分子质量、氨基酸组成、一般营养成分,评价鹰嘴豆短肽的营养价值。结果表明,中性蛋白酶和风味蛋白酶Flavourzyme制备鹰嘴豆短肽的最佳工艺参数为:复合酶添加量5 678 U/g,pH 7.0,水解时间216 min,水解温度55℃,在此条件下,短肽得率为63.79%,与碱性蛋白酶Alcalase单独酶解相比明显提高,水解度为26.74%;大部分水解产物的相对分子质量低于1 000、脂肪含量低,蛋白质、必需氨基酸等含量丰富,与FAO/WHO推荐的成人需求量模式相比,其第一限制氨基酸是蛋氨酸和半胱氨酸,与学龄儿童需求量模式相比,其第一限制氨基酸是苏氨酸,氨基酸分分别高达138.18和103.25;必需氨基酸与非必需氨基酸比值(EAA/NEAA)为0.73,接近FAO/WHO参考标准值0.6。该研究为进一步开发利用和工业化生产鹰嘴豆短肽奠定了基础。 相似文献
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Fernando D. Brignol Vitor A. G. Fernandes Renata O. Nobrega Camila F. Corrêa Keith Filler James Pettigrew Dbora M. Fracalossi 《Aquaculture Research》2019,50(3):707-716
Nile tilapia juveniles (8.35 ± 0.80 g) were fed on four levels (0.0%; 0.5%; 1.0%; 2.0%, 4.0%) of Aurantiochytrium sp. meal (ALL‐G‐RICH?), a source of docosahexaenoic acid (DHA). The 1% Aurantiochytrium sp. meal diet was compared to a control diet, which contained the same amount of DHA as cod liver oil (CLO) at 1.7% diet. Groups of 25 fish were stocked in 100 L tanks and fed twice daily until apparent satiation, for 57 days, at 28°C. Increasing dietary Aurantiochytrium sp. meal reduced the body retention of DHA and n‐3 polyunsaturated fatty acids (n‐3 PUFA) but increased the body retention of alpha‐linolenic (α‐LNA), linoleic (LOA) and n‐6 polyunsaturated fatty acids (n‐6 PUFA). Fatty acid profile in tilapia muscle was affected by increasing dietary inclusions of Aurantiochytrium sp. meal, with an increase in DHA, α‐LNA, n‐3 PUFA and n‐3 long chain‐polyunsaturated fatty acids (n‐3 LC‐PUFA) but a decrease in monounsaturated fatty acids (MUFA), n‐6 PUFA and n‐6 long‐chain polyunsaturated fatty acids (n‐6 LC‐PUFA). There was a larger body retention of DHA, α‐LNA, LOA, n‐3 PUFA and n‐6 PUFA fatty acids and a higher percentage of DHA, n‐3 PUFA and n‐3 LC‐PUFA in muscle fatty acid profile in fish fed on CLO diets than in those fed on 1% Aurantiochytrium sp. Therefore, Aurantiochytrium sp. meal is an alternative source of DHA for Nile tilapia diets. 相似文献
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Mayara de Moura Pereira Mariana Machado Evangelista Enric Gisbert Elizabeth Romagosa 《Aquaculture Research》2019,50(8):2181-2190
The aim of this study was to assess the activity of gastric, pancreatic and intestinal digestive enzymes during the embryonic and larval development of Nile tilapia (Oreochromis niloticus) GIFT strain Aqua America® 1 obtained from a broodstock fed two levels of crude protein (CP). A total of 72 females and 24 males, 10 hapas, two CP levels (32% and 38%) and six phases of embryonic (cleavage, blastula, gastrula) and larval (hatching, 7 and 10 days post hatch, dph) stages were used. The eggs were collected in cleavage, blastula and gastrula stages, 300 mg was collected, and kept in cryogenic tubes in liquid nitrogen. For the samples at larval stage, the remaining eggs were separated according to crude protein level and kept in hatcheries and samples were collected on 7 and 10 dph the same way as before. A total of 48 samples were collected: at each protein level (32% and 38% CP), four samples were collected in each phase of embryonic and larval development. Statistical differences were not observed during embryonic development for acid proteases, trypsin, amylase and lipase activity at both levels of crude protein (32 and 38% CP). Differences for acid proteases were noticed on 7 dph; trypsin and amylase on 7 dph and 10 dph. Significant differences on blastula and 7 dph for protease; as for aminopeptidase, there was significant difference on 7 dph. The data indicated early appearance of digestive enzymes in Nile tilapia broodfish receiving 32% CP taking into account the rapid growth and development of this species. 相似文献
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茶银尺蠖[Scopula subpunctaria (Herrich-Schaeffer)]是危害茶树的常见害虫之一。为了更好地在实验室内饲养此害虫,获得大量供试虫源,研究了补充不同营养对茶银尺蠖成虫寿命和产卵量的影响。结果表明,成虫补充10%蜂蜜水和10%糖水时,雌成虫平均单雌产卵量显著提高,分别为(152.5±16.83)粒和(177.5±19.01)粒;产卵期显著延长,分别为(17.8±1.08) d和(21.4±1.27) d。补充不同营养对雌成虫产卵期和产卵后期有显著影响,但对产卵前期影响不显著。补充10%糖水时,雌成虫的寿命最长,为(29.1±1.41) d,显著高于其他处理;而在10%蜂蜜水、水和对照处理下,雌成虫寿命分别为(23.8±1.15)、(14.4±0.48)、(6.3±0.37) d。补充10%糖水和10%蜂蜜水时,雄成虫的寿命分别为(21.3±0.93) d和(19.5±1.20) d,显著高于水和空白对照处理。在每个处理下,雌成虫的寿命均高于雄成虫。综上所述,10%糖水可作为成虫补充营养的最佳选择。 相似文献
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