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11.
几种豆科牧草与全株玉米混合青贮效果的研究   总被引:1,自引:0,他引:1  
将6种豆科牧草分别和全株玉米按重量比为4∶1混合后袋装青贮,取样分析青贮饲料的pH值和营养成分含量。结果表明:6种豆科牧草和全株玉米混合青贮可以调制优质青贮饲料。  相似文献   
12.

A synthesis of progress achieved thus far is provided for a 10 - year research and development program aimed at the ecological and economic rehabilitation of agroecosystems in the unirrigated portions of the central valley of Chile's Mediterranean climate region. We review our data on (1) revised management techniques aimed at restoring the gross superstructure and former levels of diversity and productivity of a mixed espinales formation; (2) selection and utilization of ecotypes of the naturalized annual Medicago polymorpha L. and the N2-fixing microsymbiont Rhizobium meliloti, for gradual improvement of espinal soil fertility; and (3) studies of the outstandingly well adapted and fast growing Canary Island tree Chamaecytisus proliferus (L. fil.) Link ssp. palmensis (Christ) Kunkel (Tagasaste), which along with about three dozen other woody nitrogen - fixing legume and several nonlegume multipurpose trees, was considered to be of potential value for deep soil layer rehabilitation combined with economic improvements. In all these subprograms, efforts were made to identify techniques or organisms that could provide short-term benefits to landowners, especially in the form of wood, fuelwood, or forage for livestock. We also consider various approaches to be added to the program over the next decade, especially in view of the overarching goal of reintegrating fragmented landscapes and combining restoration with rehabilitation and reallocation at this spatial scale.  相似文献   
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14.
Hemagglutinating activity was identified in the roots and vegetative tissues of Bengal gram using rabbit erythrocytes. The activity in the roots appears to be similar to that of the seeds in respect to their sugar inhibition property. Seed and root extracts were found to have fetuin inhibitory agglutinating activity, whereas cotyledons showed different sugar specificity. However, 7-day cotyledons and roots from 3 and 7-day plants were also found to have galactose and N-acetyl-D-galactosamine inhibitory activity. Protein profile in different tissues during their developmental stages was analyzed by SDS-PAGE. A major band at 66 kDa was common to all tissues at different stages of their development except 3-day cotyledons where 2 major bands at 22 kDa and 74 kDa were observed. Two prominent bands at 74 kDa and 86 kDa were found along with 60 kDa protein in 3-day old roots whereas a major band at 33 kDa was found in 15-day old roots. Total protein content and specific activity of hemagglutinin were measured. Increase in specific activity with lower protein content was observed in cotyledons of 15-day old plant. Specific activity was eight times higher in the roots and four times more in leaf tissues of 7-day old plants in comparison to 15-day old plants. Stems also showed a significant increase of specific activity (p = 0.013) in 7-day old plants without any significant alteration in the protein content.  相似文献   
15.
The identity and quantity of and effect ofprocessing on raffinose oligosaccharides in raw,mature seeds of lima beans (Phaseolus lunatus),pigeon peas (Cajanus cajan), African yam beans(Sphenostylis sternocarpa) and jackbeans (Canavalia ensiformis) were investigated. Sucrose,raffinose, stachyose and verbascose were identified byHPLC in all the legume seeds. The total-galactoside contents of the seeds in decreasing order were African yam beans3.84 mg/100 mg; white lima beans 3.62 mg/100 mg; creampigeon peas 3.51 mg/100 mg; red lima beans3.37 mg/100 mg; jackbeans 2.83 mg/100 mg and brownpigeon peas 2.34 mg/100 mg. The predominantoligosaccharide was verbascose in pigeon peas andstachyose in the other three legumes. Cooking unsoakedseeds brought about a greater reduction in the total-galactoside content than soaking for ninehours. The removal of oligosaccharides was higher inlegumes cooked in alkaline solution than in water.Germination quantitatively reduced raffinose,stachyose and verbascose while sucrose was increasedin all seeds except red lima beans and jackbeans.  相似文献   
16.
Effect of combinations of millet and legume and processing on digestibility, biological value and net protein utilization was evaluated using albino rats. The millets and legumes selected for the study include sorghum, pearl millet, finger millet, chickpea and green gram (P radiatus). The processes tested include dehulling, boiling, roasting, malting and baking. Among the combinations tested, the sorghum-chickpea combination had significantly (p<0.05) higher digestibility. Between the processes tested, roasting resulted in significantly higher net protein utilization. Results of biological study on biscuits prepared by using millet and legume combination flours, indicated the biscuits to be of good protein quality.  相似文献   
17.
Eight different formulations of supplementary foods (FS) based on poppedcereals (wheat, ragi, bajra and sorghum) and legumes (soy and bengalgram)were prepared. Four of the FS were produced with cereals, soy flour (SF)and bengalgram (BG) dhal and the other four were prepared with combinationsof cereals and SF. These blends were evaluated for food efficiency ratio(FER), protein efficiency ratio (PER) and net protein utilization (NPU)using growing albino rats. Skim milk powder (SMP, standard reference protein)was used in the control diet. In general the FER (0.28 to 0.34), PER (2.7to 2.9) and NPU (62 to 68) results of the FS were not significantly (p>0.05)different among the FS groups or compared with FER (0.36), PER (3.0) and NPU(73.5) of the control SMP. It is evident from the results that all eight FSwere nutritionally and biologically as good as SMP with regard to proximatecomposition, PER and NPU.  相似文献   
18.
Red (RC) or white (WC) clover were grown in mixture with grasses, ensiled and offered to dairy cows in early lactation over two successive years (48 cows per year) to compare grassland yield, feed intake, milk production and milk quality. The crops were ensiled in round bales and proportional mixtures of the second and third cut prepared each year were used to ensure that the silage treatments were representative of the crop. In addition to silage type, concentrate supplementation, without and with (10 kg/day), was included as a factor in a 2 × 2 factorial, continuous experiment. Total dry matter (DM) yield, silage chemical composition and total DM intake was hardly affected by silage type. There was no effect of silage type on milk yield and milk constituents either, except for higher milk protein content (P < 0.05) on WC and higher milk fat content of C18:3n-3 (P < 0.001), C18:2n-6 (P < 0.05) fatty acids (FAs) and sum of polyunsaturated FA (P < 0.001) and lower n-6/n-3 FA ratio (P < 0.01) on RC. Concentrate supplementation increased total DM, N and net energy intakes (P < 0.001), milk yield (P < 0.001), milk fat (P < 0.01) and protein (P < 0.001) content, decreased the milk urea content (P < 0.001), and increased the milk fat content of short- and medium-chained FAs (< C16, P < 0.001), C18:0 (P < 0.01) and C18:2n-6 (P < 0.001), decreased the content of C16:0 (P < 0.05), C18:1t11 (P < 0.001) and C18:3n-3 (P < 0.001), and increased the n-6/n-3 FA ratio (P < 0.001). The effect of concentrate supplementation was not affected by silage type, except for milk protein content where the positive effect of supplementation was stronger on WC than on RC diets (P < 0.05). This study illustrates that the white- and red clover-grass mixtures investigated were widely similar with regard to their effects on grassland yield, silage intake and milk production and milk constituents, except for a higher milk fat content of C18:3n-3 and C18:2n-6 and lower n-6/n-3 FA ratio on red clover diets. Our findings also show that N conversion efficiency from feed to milk on pure forage diets is more sensitive to changes in dietary protein intake than silage diets containing cereal based concentrates.  相似文献   
19.
As livestock production has increasingly intensified resulting in larger and more specialised farm units, the role of grassland in the production system has been marginalised. The change in EU policy, however, may make grass as feed more competitive and thereby give grassland the opportunity for a comeback. The challenge for research and grassland farming practices is to reflect this new framework. This paper reviews different production and management systems - mainly focusing on grazing systems - within intensive dairy farming and aspects of feeding and quality of herbage in order to propose areas of special interest within the new framework. Farming systems based on a high proportion of roughage, such as in organic farming, and systems based on legumes need to be further developed. There is a need for an increased research effort in the area of interaction of supplementary feeds and seasonal effects and also in the area of the interaction of N and carbohydrate degradation in the rumen with milk response and N efficiency. Additionally, time-restricted systems based on a better understanding of animal behaviour should be emphasised in order to maintain a high grass intake and reduce the excretion of nitrogen on pasture. The interaction between grassland management and new technology such as automatic milking will be important in order to keep a high proportion of the dairy cows on pasture.  相似文献   
20.
在弃耕地上种植豆科牧草,出苗前施用克芜踪除草剂,对杂草的株防效为13.7%~36.6%,鲜重防效为33.4%~80.4%。克芜踪对防除有害杂草刺儿菜最为有效。尤其是在有灌溉条件下,刺儿菜的株防效平均为89.1%,鲜重防效平均为96.3%。在无灌溉条件下,喷施克芜踪豆科牧草的鲜重和密度有不同程度的下降;在有灌溉条件下,喷施克芜踪豆科牧草的高度较对照平均提高13.9%,密度提高85.8%,鲜重增加513.7%。说明克芜踪除草剂对抑制杂草,促进豆科牧草生长有明显效果  相似文献   
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