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71.
The basal diet (C), with 0.20% medicinal herbs (M) and 0.30% Bacillus (BM1), with 0.10% medicinal herbs and 0.15% Bacillus (BM2), and with 0.30% Bacillus (B), was used to feed white shrimps (Litopenaeus vannamei) (1.91 ± 0.03 g) in order to assess survival, growth, body composition, and digestive enzyme activity. At the end of the feeding trial, survival ranged from 95.83 to 98.33% with no significant difference (> 0.05) among all groups. Growth measured as weight gain was significantly (< 0.05) higher in shrimp fed with BM2, BM1, and M compared to that of C. However, no significant differences were found among B, BM1, and M. In the case of specific growth rate, the shrimp fed with BM1 and BM2 exhibited significantly (< 0.05) higher values than that of C. The contents of body moisture, crude protein, and ash seemed to be unaffected by the feed supplements, though lipid content was found to be significantly (< 0.05) different among the treatments. The shrimp fed with BM1 and BM2 had the lowest and highest lipid contents, respectively. The digestive enzyme activity assessed using shrimp hepatopancreas revealed that the activities of amylase and protease in shrimp fed with BM2 were significantly (< 0.05) higher than those of C at the end of the 2nd and 6th weeks. However, better performance of the specific amylase activity was shown by the shrimp fed with B at the end of the 8th week.  相似文献   
72.
以内蒙古赤峰市阿鲁科尔沁旗沙日温都栎林自然保护区蒙古栎林为主要研究对象,研究不同林分密度对林下草本植物多样性的影响。结果表明,研究区内共有13科、14属、16种草本植物;Simpson指数、Shannon-Wiener指数、Pielou均匀度指数和物种丰富度指数均随着林分密度的增加呈先增大后减小的趋势,当林分密度为750株/hm2时,林下草本植物多样性指数达到最大值;林分密度与Shannon-Wiener多样性指数、Pielou均匀度指数、Simpson多样性指数、物种丰富度指数、树高、胸径均呈极显著负相关,与郁闭度呈极显著正相关,与枝下高不相关。综上所述,最合理的蒙古栎林密度为750株/hm2,该密度下最有利于蒙古栎林及林下草本植物生长发育。  相似文献   
73.
双孢蘑菇新型栽培基质配方筛选   总被引:2,自引:1,他引:1  
针对南京地区双孢蘑菇传统的稻草、牛粪栽培法难以再提高双孢蘑菇的产量、质量和栽培效益,提高农民神植效益的问题,采用废弃中药渣替代部分的稻草、牛粪进行合理的调配,以牛粪:稻草:中药渣:其他辅料为4:4:20:2为理想配方,该基质与传统的稻草、牛粪栽培基质比,理化性状更加优化,易于处理,菌丝生长快,出菇快,产量提高18.8%;微量元素Fe、Zn,矿质元素P、K及蛋白质含量明显增加,每1 m~2可净增产值4.9元,有较好的市场前景。  相似文献   
74.
目的:确定蕨类太白七药的植物资源及分布情况,为其合理开发利用提供依据。方法:通过查阅相关文献资料,野外实地采集,走访调查,标本鉴定,对太白山蕨类七药植物种类,药用部位,性味,植物形态,分布,生长环境,功效等进行了调查分析。结果:蕨类太白七药共6科6属9种,占太白山蕨类科、属、种的约28.6%,15.4%,8.2%;性多苦寒,功效主要以清热解毒,利水通淋为主;多生长在林下、山谷或溪边。结论:蕨类太白七药植物资源丰富,民间用药历史悠久,采集方便,但开发利用程度还不够,可以在不破坏生态平衡的情况下,加大对蕨类太白七药资源的开发利用。  相似文献   
75.
An experiment was carried out to assess the feeding effect of Chinese herbal medicine on N balance, ruminal fermentation characteristics, kinetics of plasma glucose, leucine and energy metabolism in sheep kept at thermoneutral environment (23°C) or exposed to cold (2–4°C). Four sheep were subjected to either mixed hay (MH‐diet) or hay supplemented with 2% of a traditional nourishing Chinese herbal medicine mixture (Astragalus root, Angelica root and Atractylodes rhizome; CHM‐diet) over two 23‐day periods using a crossover design. Cold exposure was conducted for 5 days. The isotope dilution of [U‐13C]glucose with open circuit calorimetry was used to determine the turnover and oxidation rates of plasma glucose and metabolic heat production. The rate of plasma leucine turnover was measured with an isotope dilution method using [1‐13C]leucine. N intake was higher, N excretion through faeces was lower and N digestibility was higher for the CHM‐diet than the MH‐diet. Rumen pH was lower, concentration of rumen NH3 was higher, concentrations of rumen total VFA and acetate tended to be higher and propionate was higher for the CHM‐diet compared with the MH‐diet. Turnover rate of plasma glucose was higher for the CHM‐diet than the MH‐diet and increased during cold exposure. Oxidation rate of plasma glucose did not differ between diets and also between environments. Turnover rate of plasma leucine was higher for the CHM‐diet compared with the MH‐diet but remained similar between environments. Heat production was greater for the CHM‐diet than the MH‐diet and increased during cold exposure. No significant diet × environment interaction was detected. The present results demonstrated that plasma glucose and energy metabolism were enhanced by both Chinese herbal medicine and cold exposure; plasma leucine metabolism was enhanced by Chinese herbal medicine but with lack of change in response to cold exposure in sheep under the conditions of the current experiment.  相似文献   
76.
针对延边地区丰富的山野菜资源及优越的气候条件,分析了延边地区山野菜开发与利用的前景、必要性,提出目前延边地区开发与利用山野菜存在的问题及对策。  相似文献   
77.
<正>原产于安徽省宣城市的地道中药材宣木瓜(Chaenomeles sinensis)隶属蔷薇科(Rosaceae),为常用中药木瓜的上品,是与藏红花、甘枸杞、川杜仲齐名的四大名贵中药材之一。除药用之外,近年也被用于化妆品和保健品领域[1]。此外,由于树冠优美、花团锦簇,宣木瓜还被栽培用于观赏;同时,因其耐旱耐瘠,对土壤要求不高,又常被作为退耕还林的引种树种。因此,宣木瓜是一种集经济、生态、社会等多种效益于一身的优良树种,被广泛种植于安徽、云  相似文献   
78.
Reduction of shrub cover in Mediterranean shrublands is considered as a method of optimising forage and animal production. In this study, forage production in grazed and protected plots and grazing responses of small ruminants in cleared (25% shrub cover), slashed (34% shrub cover) and not treated (control, 55% shrub cover) kermes oak (Quercus coccifera L.) shrublands were compared during the spring seasons of 1992, 1993 and 1994. The alterations in shrub density were done in October 1991 and pastures remained ungrazed until spring of 1992. Clearing and slashing of shrub vegetation resulted in higher amounts of available herbaceous forage and useable browse. At the end of the growing season, averaged across years, herbaceous biomass was generally two to three times higher in the treated shrublands than in the control; also, browse biomass was slightly less (1,078 vs 1,533 kg/ha) but easily accessible because of the open structure and the lower height of the sprouting shrubs. There were generally no grazing response differences between the cleared and slashed pastures. However, grazing animals (sheep and goats) had a higher bite rate (bites/min; P 0.05) in the treated pastures than in the control. Levels of crude protein in the forage selected by animals were higher (P 0.05) in the treated pastures than in the control. Animals in the improved pastures maintained diets that were significantly more digestible (53.5%) than those in the control pasture (48.5%). Neutral detergent fibre and lignin contents of animal diets were similar in the improved pastures but lower (P 0.05) than those of the control. It is concluded that removing of woody vegetation in Mediterranean shrublands results in increased forage production (available herbage and useable browse) and improved forage quality and availability for small ruminants.  相似文献   
79.
观察不同浓度的复方多糖、黄芪多糖(APS)、当归多糖(ASP)及淫羊藿多糖(EPS)对正常罗曼雏鸡免疫功能的影响。将260只1d龄健康罗曼雏鸡随机分为13组,每组20只。分别于1d龄皮下注射生理盐水以及复方多糖、APS、ASP、EPS,连续注射7d。于7、14、21、28、35、42、49、56d龄采血,检测淋巴细胞转化率和ND—HI抗体效价。试验结果表明:使用复方多糖、APS、ASP、EPS后,各试验组外周血淋巴细胞转化率和ND—HI抗体效价明显升高。复方多糖可使外周血淋巴细胞转化率和ND—HI抗体效价显著高于其他各多糖组。复方多糖、APS、ASP、EPS均可提高鸡的外周血淋巴细胞转化率和ND—HI抗体效价,其中复方多糖效果最好。  相似文献   
80.
王俊丽  张要齐  孙雪峰  张新蕾  陈静  张妍  张玲 《安徽农业科学》2012,40(26):12947-12948,12951
[目的]比较2种体外抑菌试验结果,筛选猪大肠杆菌的抑菌中药,为临床用药及开发中兽药制剂提供依据。[方法]采用水煎法制备18种中药水提物,分别通过试管二倍稀释法和管碟法进行体外抑菌试验。[结果]试管二倍稀释法中18种中药均表现出一定的抑菌效果,但管碟法测定部分中药表现出耐药性。2种测定方法中黄连、大黄抑菌效果最强,对猪大肠杆菌的MIC均为7.82 mg/ml,MBC值也相对较高,抑菌圈直径分别为25.28和22.84 mm,而穿心莲、白头翁、防风等抑菌效果相对较差。[结论]不同中药对猪大肠杆菌的抑菌活性不同,采用不同的测定方法所得试验结果既有一致性又有差异性。  相似文献   
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