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长白山区冬季寒冷漫长,蜂群越冬长达130～140天。由于群势弱、蜂种越冬性能较差、越冬环境不良等因素,常导致越冬蜂群饲料消耗量大,个体死亡率高,蜂群严重削弱,影响了来年的春繁和经济效益。为了探索降低越冬蜂群体消耗的技术,我们进行了不同群势、不同品种蜜蜂越冬性对比以及改善蜂群越冬环境条件的试验。 相似文献
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因东北地区越冬时间长,气候寒冷,与其他省份蜂群管理有很大的不同,所以东北地区要使蜂群顺利越冬,合理布置越冬蜂巢是安全越冬的必要保障。那么怎样才叫合理布巢呢?主要根据蜜蜂生物学特点,在越冬期间取食饲料的规律,人为创造便于结团保温取食的便利条件,这就叫做合理布巢。一、布巢基本条件1.根据群势应达到越冬基本蜂数,单王单箱的越冬蜂群应不少于5框足蜂。2.单箱双王群每侧应在3框足蜂。3.优质足量的越冬饲料,保证无甘露蜜饲料,单脾重量应达2~2.5kg以上,蜜脾封盖率达60%以上。 相似文献
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蜂群越冬．分室内越冬和室外越冬。由于东北地区比较寒冷,养蜂者习惯于蜂群室内越冬。室内越冬的优点是：安全,便于管理等。一、蜂群人室1．入室时间：蜂群入室的时间要根据当地的气候变化情况而定。当外界气温基本稳定,即白天中午最高气温下降到0'℃以下,夜间最低气温下降到-15℃以下时,可将蜂群搬进越冬室具体时间还要根据群势和越冬室的情况灵活掌握。2．蜂箱的搬运和安排：搬运蜂箱要保持箱体平衡,轻搬轻放,力求巢牌在箱内不串动位置,不互相挤碰,蜂团不受震动,保持安静状态。搬入越冬室的蜂群要根据越冬室的规格排列成2行或4… 相似文献
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我地处伊春市乌伊岭林业局以北 2 4公里美丰林场 ,小兴安岭北坡。此地蜂群越冬期为 10月至来年 4月初 ,“清明”前后出窖 ,时间长达 6个月。冬季极限温度零下 39℃ ,正常温度为零下 2 0～ 2 6℃。真可谓寒冷地区。本文所述寒冷地区的蜂群越冬后期管理 ,只限室内越冬蜂群。我在此地养蜂近 2 0年 ,往往是成功一年 ,失败一年。不是箱内冻冰大部份蜂冻死 ,就是伤热蜜蜂拉稀全群死亡。总结多年教训 ,得出如下结论 :一、越冬群势 :我个人认为蜂群越冬并非群势越强越好。我饲养的是美意蜂和喀尔巴阡蜂杂交种。即蜂王是纯美意 ,而工蜂是美×喀单交种… 相似文献
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陕北地区蜂群越冬长达 5个月之久。为了使蜂群安全顺利地越冬 ,为下年春繁打好基础 ,应采取如下措施进行管理。一、强群越冬强群越冬是陕北地区蜂群越冬的重要基础。蜂群至少要达到 4框足蜂以上 ,放 5～ 6张脾为宜。有了这样的群势 ,才能安全越冬。二、要有充足的越冬饲料越冬饲料必须充足 ,蜜脾上部封盖 ,下部留少数空房 ,使蜜蜂在巢脾下部结团 ,这样蜂团距巢门近 ,空气流通 ,温湿度较平衡 ,蜂团不易受伤热 ,取食较容易 ,蜂群安静 ,能减少死亡率和饲料消耗。三、抓紧治螨蜂群断子后 ,进入越冬阶段 ,蜂螨全部转移到工蜂的体表 ,必须选择晴天… 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 相似文献
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Billinghurst RC Brama PA van Weeren PR Knowlton MS McIlwraith CW 《American journal of veterinary research》2004,65(2):143-150
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis. 相似文献