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991.
以北方盆栽蓝莓美登和北蓝为研究对象,通过人为温度控制,促使盆栽蓝莓提前开花。研究表明,盆栽美登(Blomidon)在需冷量达到1200h,盆栽北蓝(Northern blue)在需冷量达到1000h情况下,可以通过温度调控,打破盆栽蓝莓休眠期,达到提前开花的目的。  相似文献   
992.
龙烟7号是黑龙江省农科院牡丹江分院以密叶香为母本、牡晒84-1-5为父本杂交选育而成的晒烟新品种。2014年3月通过黑龙江省农作物品种审定委员会审定并定名推广。该品种植株为橄榄形,株型收敛、茎叶角度小,叶形宽椭圆,大田生育期84天,属中熟品种。幼苗及大田生长势强、整齐,烟叶成熟较集中。原烟外观质量优良,色泽红黄,油份较足,弹性好。高抗赤星病和普通花叶病。据多年多点试验结果,平均产量为2994kg/hm2,产值32963.9元/hm2,均价11.01元/㎏,中上等烟比例76.57%,分别比对照龙烟二号提高11.1%、15.9%、4.3%、5.5%。  相似文献   
993.
白龙江中游千枚岩出露区泥石流分布集中、暴发频繁、灾害严重,生态修复难度大。分别从该区社会经济、气候、地质角度阐述了泥石流生态修复的难点;从水土互相作用与泥石流流体结构、土体与土体结构、沟谷地貌、坡面形态、泥石流沟流域形态揭示了泥石流发育机制,以及植被在其中的作用机制。分析了传统水平台型整地与竹樊保持水土技术、植苗与微圃植树法造林技术、传统造林树种选择与生态公益植被物种选择技术、常规混交造林与毒—刺混交植被植物种类配置模式等4组基本技术的优缺点及其适用范围,分别确定了生态公益植被与经济利用植被的营建技术。最后,根据研究区地貌分异特点和当地社会经济状况,将泥石流沟分为清水区、泥石流形成区、经济利用区、道路工程影响区4个功能单元,分别论述生态修复技术,有机结合新技术与传统技术集成为泥石流生态修复技术体系。  相似文献   
994.
白龙江中游泥石流生态修复植物筛选   总被引:1,自引:0,他引:1  
针对白龙江中游泥石流生态修复实际,分析提出生态修复植物选择原则,选择出18种生态修复植物,并简要论述了各植物种形态、繁衍特点、生态习性和生态功用。  相似文献   
995.
中山杉的优良特性备受国内外学者的关注。国内有不少关于中山杉的研究报道,学者们从不同层次研究中山杉的优良特性,以更好的利用中山杉,发挥其生态、效益和经济效益。本文从中山杉的来源、抗逆性、育苗技术、景观及推广应用等几个方面对近年来中山杉的研究进展进行介绍,以期为中山杉资源的综合开发利用提供依据。  相似文献   
996.
从广西某鸡场的发病鸡群中采样病料,接种10日龄SPF鸡胚后分离得到1株病毒,并命名为GL株,经微量血凝和微量血凝抑制检验为H9亚型禽流感病毒。测序结果分析显示,HA蛋白裂解位点的氨基酸序列为RSSR↓GLF,与低致病性禽流感病毒的基序一致。HA基因分型结果表明,GL株属于4.2.5分支。BLAST结果显示,HA基因序列与BJ0309株相似性最高,达99%。相似性比较结果表明,HA基因、蛋白与近年来国内流行的GX55等4.2.5分支H9亚型禽流感病毒相似性较高,分别为94.1%~98.8%和96.4%~99.3%,而与国内常用疫苗株SS、F、SD696等4.2.3分支H9亚型禽流感病毒相似性较低,分别为88.8%~89.8%和91.2%~92%。由此可见,分离的GL株属于4.2.5分支,与近年来国内流行株类似,并与常用疫苗株存在了一定的差异。  相似文献   
997.
公司化运营丹寨模式是贵州省建立的一种新的基层兽医服务模式。为推广这一新模式,从模式的成立背景、项目营运、收入分配和运转成效等方面进行了系统介绍,从村级防检员收入、服务能力等方面剖析了该新型模式的先进性,并提出了推动该模式持续健康发展的相关建议。  相似文献   
998.
  1. The effects of different fibre sources on the growth performance, carcass characteristics and gastrointestinal tract development were studied in growing Greylag geese (Anser anser).

  2. Four experimental diets were formulated with corn (maize) straw silage (CSS), steam-exploded corn (maize) straw, steam-exploded wheat straw, and steam-exploded rice straw as fibre sources. A total of 224 male Greylag geese at 28 d of age were randomly assigned to one of the 4 experimental diets.

  3. The birds fed on the CSS diets had higher average daily feed intakes than those fed on the steam-exploded straws. However, the 4 treatments had similar average daily gain, which contributed to significant differences in feed conversion ratios. The different fibre sources had no significant effects on the carcass characteristics.

  4. The CSS-fed birds had larger gizzards and lower relative length of the caeca than the other three groups. However, the relative weights and lengths of the other gut segments, the relative weights of major organs and the pH values of the gastrointestinal contents were similar between the 4 treatments.

  5. It was concluded that straw fibres with different physico-chemical properties exerted an effect on daily feed intake and gastrointestinal development, especially for the gizzard. The pretreatment of straw had a large effect on utilisation efficiency and animal performance. Steam explosion is a promising straw pretreatment for inclusion in diets for geese.

  相似文献   
999.
The present study evaluates the effects of embryonic age and proteolytic enzymes on the isolation and primary culture of chicken enterocyte and to establish an effective technique for chicken intestinal epithelial cell (IEC) cultivation. Fourteen‐day‐old, 16‐day‐old and 18‐day‐old embryos (average weight: 52.23 ± 0.76 g, 50.86 ± 0.99 g, 48.98 ± 1.03 g) were the source for preparation of enterocyte culture, and trypsin‐ethylene diamine tetraacetic acid, collagenase, thermolysin and combination of collagenase and thermolysin were used for digestion medium. Optimal culture protocols were determined by qualitative assays of proliferation. Cells isolated by using 14‐day‐old embryo and collagenase obtain the best attachment and growth in culture, and the production of continuously growing IEC cultures. Thus, we conclude that the use of collagenase as a dissociating enzyme and 14‐day‐old embryo as a source can be advantageously applied to the isolation of chicken IEC and this method may be useful for various applications and basic studies of the intestinal tract concerning such objects as physiology, immunology and toxicology.  相似文献   
1000.
This experiment was conducted to study the effects of different levels of compound Chinese medicine on growth performance,nutrients apparent digestibility,immune function and slaughter performance of weaning Rex rabbits.70 healthy Rex rabbits at age of 60 days were divided into 7 groups with 5 replicates per group and 2 rabbits per replicate.Group Ⅰ was fed with basic diet as control group,group Ⅱ was fed the basal diet supplemented with antibiotic (contains 50 mg/kg milligrams bacitracin zinc,10 mg/kg colistin sulfate).The other five groups (Ⅲ,Ⅳ,Ⅴ,Ⅵ and Ⅶ) were fed the basal diet supplemented with 1%,2%,3%,4%,5% compound Chinese medicine,respectively.The pre-test period lasted for 7 days and the trial period lasted for 45 days.The results showed as follows:①The ADG in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ and Ⅲ (P< 0.05),the F/G in group Ⅳ was significantly lower than that in other groups (P< 0.05).②The apparent digestibility of DM in group Ⅳ was significantly higher than that in groups Ⅰand Ⅱ (P< 0.05),the apparent digestibility of DM in group Ⅶ was significantly higher than that in group Ⅰ (P< 0.05).The apparent digestibility of CF in group Ⅳ was extremely significantly higher than that in group Ⅰ (P< 0.01),the apparent digestibility of CF in group Ⅶ was significantly higher than that in group Ⅰ (P< 0.05).The apparent digestibility of NDF in group Ⅳ was extremely significantly higher than that in group Ⅰ (P< 0.01),and significantly higher than that in groups Ⅱ,Ⅲ,Ⅴ and Ⅶ (P< 0.05).The apparent digestibility of ADF in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ,Ⅴ and Ⅶ (P< 0.05).The apparent digestibility of CP in group Ⅳ was significantly higher than that in groups Ⅰ and Ⅱ (P< 0.05).③ There were no significant differences in the contents of IgG,IgA and IgM of serum among all groups (P> 0.05),the spleen index in group Ⅳ was significantly higher than that in groups Ⅰ,Ⅱ,Ⅲ and Ⅴ (P< 0.05).④There were no significant differences in the slaughter rate,half eviscerated slaughter rate and all eviscerated slaughter rate among all groups (P> 0.05).In summary,adding compound Chinese medicine and antibiotics in the feed both could improve the growth performance,nutrients apparent digestibility,immune function and slaughter performance of weaning Rex rabbits,and the appropriate compound Chinese medicine level in the diet of weaning Rex rabbits was 2%.  相似文献   
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