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81.
本试验的氮源是纯化大豆蛋白(IsolatedSoybeanProtein,ISP)和尿素(NPN),按80:20、50:50和20:80分3组;碳水化合物源分别是从干草中提取的中性洗涤纤维(NDF)、玉米淀粉和蔗糖,按10:85:5、10:80:10、10:75:15、30:65:5、30:60:10、30:55:15、50:45:5、50:40:10和50:35:15分9组的3×9因子实验设计。应用体外尼龙袋发酵技术,研究了奶牛日粮不同来源氮和碳水化合物及其比例对干物质(DM)体外降解率的影响。结果表明,过量补充尿素及随着日粮中淀粉和蔗糖比例的增加,日粮干物质的体外降解率均下降。根据试验结果,建议在泌乳期奶牛的全混合日粮中尿素的补充量应低于干物质的2.8%,非结构性碳水化合物的含量不应超过干物质的45%。  相似文献   
82.
The immunization procedure of DNA vaccine pcDNA–TA4–IL-2 of Eimeria tenella, including route, dose, time of immunization and age of primary immunization of chicken, was optimized. The stability and the cross-species protection of the vaccine were also analyzed. Efficacy of immunization was evaluated on the basis of oocyst decrease ratio, lesion score, body-weight gain and the anti-coccidial index (ACI). Chinese Yellow chickens were randomly distributed into corresponding groups (30/group). The challenged, unchallenged and vector control groups were designed. The results illustrated that 25 μg was the optimal dose and intramuscular injection was the most effective route to induce protective immunity. There were no significant differences of ACIs between boosting and non-boosting groups. Storage time and temperature had little effect on the immunizing efficacy of the vaccine. The vaccine could provide partial cross-protection against the challenge with E. necatrix and E. acervulina, but not with E. maxima.  相似文献   
83.
The effect of organic acids (OA) and dicalcium phosphate (Pi) supplementation in the feed of Labeo rohita fingerlings was studied by formulating seven practical diets, designed as D1 with no feed additives {dicalcium phosphorus (Pi) and organic acid (OA) blend} while, D2, D3, D4 and D5 were supplemented with Pi at the graded levels of 5, 10, 15 and 20 g/kg, respectively, whereas D6 and D7 contained blend of OA at 15 and 30 g/kg, respectively. The diet supplemented with OA blend exhibited increase (p < .05) in growth of L. rohita fingerlings compared with the diet supplemented with Pi. The OA supplementation at both levels showed significant improvement in nutrients digestibility and minerals absorption in fingerlings. Moreover, in case of muscle proximate composition, crude fat (CF) and crude protein (CP) were increased (p < .05) with the inclusion of OA blend in the diet while crude ash (CA) was improved by Pi supplementation. Additionally, digestive enzyme activities were not affected (? .05) by OA blend supplementation while increased activities were observed in the fingerlings fed with Pi diet. Consequently, supplementation of OA blend in the diet improved the growth performance and nutrient status while Pi enhanced digestive enzyme activities of L. rohita fingerlings.  相似文献   
84.
A specifically-synthesized water-soluble photochromic acid dye has been applied by screen printing on to silk, wool and nylon. The influence of processing parameters and the nature of the substrate on the photochromic response of the printed materials has been evaluated using specifically-developed colour measurement methodology. The printed substrates show photochromic colour change from weakly coloured to an intense blue colour under sunlight or UV irradiation. In most cases, the photochromic colour build up is higher on wet substrates than after drying. Computer aided molecular modelling techniques have been used to explain aspects of the photochromic behaviour.  相似文献   
85.
The ability of the probiotic bacterium Sulfitobacter to inhibit the growth of two virulent strains (psh-9019 and ATCC 43306) of the fish pathogenic bacterium Vibrio anguillarum was tested. Probiotic and pathogenic bacteria were inoculated individually or together in three different types of media. Two of the phytoplankton media tested were filtrates of phytoplankton Chlorella vulgaris cultures, either the live phytoplankton (live-CV) or a condensed phytoplankton (condensed-CV). Phytoplankton culture medium, ESM, was used as a control medium without phytoplankton. In ESM, Sulfitobacter decreased the viable cell counts of both V. anguillarum strains by tenfold. In the live-CV filtrate, V. anguillarum was eradicated by Sulfitobacter within one week. Although colony counts of strain ATCC 43306 declined during the two-week co-incubation with Sulfitobacter, its growth was not fully inhibited; however, the counts were tenfold lower than that in control ESM medium. Neither of the pathogenic V. anguillarum strains were inhibited nor eradicated by Sulfitobacter in the condensed-CV filtrate medium. Our study indicates that commercially available condensed phytoplankton can enhance the growth of V. anguillarum. Thus, the addition of live phytoplankton, including the introduction of Roseobacter clade bacteria to fish larvae tanks, leads to better biocontrol of the fish pathogen V. anguillarum.  相似文献   
86.
The democratic evaluative tradition has sought to change evaluation practice towards approaches and techniques that generate diverse forms of knowledge and foster public deliberation over a programme's merit and worth. This paper locates one evaluation method, ‘Most Significant Change’ (MSC), within this tradition. Drawing on two different evaluations – one, of a comprehensive economic sector assistance package to the Government of Tokelau, and the other of a psychosocial and academic support intervention for pre‐adolescent children in conflict‐affected regions of the Gaza Strip – the paper provides evidence of how MSC can capture unexpected outcomes, act as a tool for real‐time formative learning, and expose the competing theories, logics and values behind programme activity. The examples within the paper also provide evidence of how MSC begins to redistribute traditional power relationships in assessing the merit and worth of observed impacts by increasing the legitimacy of local programme knowledge, and engaging all parties in evaluative decisions. By doing so, MSC, the paper argues, better serves the purposes of learning, improvement and mutual accountability which should sit at the core of good development practice.  相似文献   
87.
A solution culture study was conducted to compare the phosphorus (P) remobilization efficiency of four wheat cultivars under induced P deficiency. Wheat cultivars, i.e. Sarsabz, NIA-Sunder, NIA-Amber and NIA-Saarang were initially grown on adequate P nutrition for 30 days and then exposed to P-free nutrient solution for next 15 days to study P remobilization. Completely randomized design (CRD) with ten replicates per cultivar was employed. Cultivars varied for biomass production, P concentration, P uptake, and P utilization efficiency at both harvests. Overall, more than 75% of absorbed P was mobilized from older leaves to younger leaves as well as roots of all cultivars during P-omission period. However, cultivars could not produce significant variations (P < 0.05) in P remobilization, which implied that P remobilization was only a stress response to P deficiency in wheat cultivars and it could not be related to P utilization efficiency of these cultivars.  相似文献   
88.
Animal rearing is the major occupation of most population of South Asian countries. Due to lack of resources and limited approach to modern medicine, most of the livestock raisers prefer to use plant-based traditional medicine also referred to as ethnoveterinary medicine (EVM). Indeed, the use of medicinal plants in South Asia dates back to several centuries with documented evidences. However, there is currently a dearth of documentation and compilation of use of medicinal plants for animal diseases in this part of the world. This review aims to provide an up-to-date compilation of common medicinal plants used for the treatment and/or management of common animal diseases in South Asian countries. Extensive literature search was conducted online and relevant data was retrieved from well-known scientific databases. A total of 276 plants belonging to 95 families have been documented to be in common use for managing 14 different categories of animal diseases. Solanaceae, Lamiaceae, Fabaceae, and Leguminosae were most common plant families in terms of their plant species used for EVM. Gastric diseases were commonly reported and accounted for 72 species of plants used for its treatment followed by the miscellaneous disorders category and skin diseases comprising of 65 and 39 plant species respectively. Herbs accounted for 46% of the total plant species, followed by trees (33%), and shrubs (18%). The EVM were applied through different routes of administration; oral administration accounted for 72% followed by topical application 27%, while burning of plant parts to create smoke around animals to repel insects was less common (1%). It is anticipated that the present review will stimulate further ethnoveterinary research among livestock disease management practices in South Asia.  相似文献   
89.
The performance of the novel chitin metal silicate (CMS) co-precipitates as a single multifunctional excipient in tablet formulation using direct compression and wet granulation methods is evaluated. The neutral, acidic, and basic drugs Spironolactone (SPL), ibuprofen (IBU) and metronidazole (MET), respectively, were used as model drugs. Commercial Aldactone®, Fleximex® and Dumazole® tablets containing SPL, IBU and MET, respectively, and tablets made using Avicel® 200, were used in the study for comparison purposes. Tablets of acceptable crushing strength (>40 N) were obtained using CMS. The friability values for all tablets were well below the maximum 1% USP tolerance limit. CMS produced superdisintegrating tablets (disintegration time < 1 min) with the three model drugs. Regarding the dissolution rate, the sequence was as follow: CMS > Fleximex® > Avicel® 200, CMS > Avicel® 200 > Dumazole® and Aldactone® > Avicel® 200 > CMS for IBU, MET and SPL, respectively. Compressional properties of formulations were analyzed using density measurements and the compression Kawakita equation as assessment parameters. On the basis of DSC results, CMS co precipitates were found to be compatible with the tested drugs. Conclusively, the CMS co-precipitates have the potential to be used as filler, binder, and superdisintegrant, all-in-one, in the design of tablets by the direct compression as well as wet granulation methods.  相似文献   
90.
Changes in nitrate reductase, i.e. NR (E.C. 1.7.1.1) activity, peroxidase (E.C. 1.11.1.14) activity, soluble sugars and phenols were monitored at various time intervals from day 0 to 60 during in vitro adventitious shoot regeneration from leaflet explants of Albizia procera (Roxb.) Benth. The explants were incubated on semi-solid Murashige and Skoog medium supplemented with 2.6 g l?1 Phytagel®, 2.5% sucrose, 10 μM BAP, 1 μM NAA and 15 μM AgNO3. NR activity, soluble sugars and phenols exhibited initial sharp rise on around day 20 followed by steep decline on day 25, whereas peroxidase activity peaked on day 50, highlighting significance of early input of nitrogen and energy and late emergence of lignification process for cellular differentiation and organization into adventitious shoot primordia. Morpho-anatomical changes in leaflets at various stages of in vitro adventitious shoot formation also followed the endogenous biochemical pattern.  相似文献   
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