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1.
从 1992年到现在 ,内蒙古通过推广胚胎移植技术在种源生产和提高种畜质量上取得了显著的经济效益和社会效益。据介绍 ,家畜胚胎移植技术投入畜牧业生产实践以来 ,牛羊胚胎移植技术已成为内蒙古牧业的一项新型实用技术 ,在种源生产和纯种扩繁上发挥了十分重要的作用。到目前 ,内蒙古累计生产牛羊胚胎 16 893枚 ,移植受体牛羊 176 2 5枚 ,其中冷冻胚胎移植妊娠率分别达到 46 %和 5 6 %以上。内蒙古家畜改良站与宝克种畜有限公司等单位合作 ,进行肉用种牛羊的规模化胚胎移植 ,形成了年产纯种安格斯、海福特牛 10 0 0头 ,纯种肉羊 2 0 0 0只以上…  相似文献   

2.
毛乌素沙地高等植物资源   总被引:8,自引:0,他引:8  
为了解禁牧和退耕后毛乌素沙地的植被状况,2002-2004年在查阅相关资料和野外调查的基础上,对沙地高等植物资源进行统计与分析。结果表明:毛乌素沙地的高等植物共有1106种,分属于98科420属;主要科有菊科、禾本科、豆科、蔷薇科和藜科;主要属有蒿属、黄芪属、葱属、柳属、杨属;主要种有油蒿、沙竹、牛心朴子、沙柳和乌柳;植被类型主要有草原植被、草原和荒漠灌丛、沙生植被、草甸植被、盐生植被、沼泽和沼泽性植被、水生植被,其中沙生植被占主导地位,其次为草甸植被;植物群落主要有油蒿群落、油蒿—柠条群落和沙柳、乌柳、沙棘组成的“柳湾”;简述了毛乌素沙地的植被特征,提出灌木应为该区植被建设的主要物种,加强灌、草、乔之间的结合。  相似文献   

3.
在结缕草萌动前对结缕草草地进行火烧处理,研究生长季内不同月份火烧对结缕草草地杂草的控制效果。结果表明:整个生长季内火烧对结缕草草地杂草株数、植物量(地上,干重)均有较好的防控效果,平均防控效果分别为23.97%、39.90%;株数防控效果最好为5月份,为40.95%,植物量防控效果最好为10月份,为65.74%;火烧对结缕草草地杂草的防控效果在春季主要表现在防控杂草的数量(株数),在秋季主要表现在防控杂草的重量(地上植物量)。  相似文献   

4.
对福泉市牛羊养殖产业发展现状及优势、存在的主要问题进行了剖析,有针对性地提出了今后牛羊养殖产业发展的对策和措施,为今后福泉牛羊养殖产业的发展提供参考借鉴。  相似文献   

5.
【目的】评价内蒙古乌拉盖天然草原不同放牧区混合优势牧草营养价值,确定放牧家畜营养供给和最佳放牧区。【方法】测定和分析内蒙古乌拉盖天然草原 8 个主要放牧区青草期混合优势牧草营养成分、结构性碳水化合物、体外瘤胃发酵特性,并对其营养价值进行综合评定。【结果】乌兰察布嘎查放牧区混合牧草粗蛋白(CP)含量显著低于其他放牧区(P<0. 05),乌拉盖水库放牧区混合牧草粗灰分 (Ash)含量显著高于其他放牧区(P<0. 05),乌兰察布嘎查放牧区和斯仁音昭村放牧区混合牧草钙 (Ca)和磷(P)含量显著高于其他放牧区(P<0. 05),而宝克牧场放牧区混合牧草可溶性碳水化合物 (WSC)含量最高(P<0. 05);乌兰察布嘎查放牧区混合牧草酸性洗涤纤维(ADF)、纤维素含量显著高于其他放牧区(P<0. 05),查干哈达村放牧区混合牧草中性洗涤纤维(NDF)、酸性洗涤木质素(ADL)、 半纤维含量显著低于其他放牧区(P<0. 05);瘤胃体外发酵 12~48 h,发酵液 pH 无明显变化,查干哈达村放牧区混合牧草产气量(GP)、体外干物质降解率(DMD)和体外中性洗涤纤维降解率(NDFD)随时间增加呈现递增趋势,均显著高于其他放牧区(P<0. 05)。【结论】内蒙古乌拉盖天然草原查干哈达村放牧区混合牧草营养价值最佳。  相似文献   

6.
对中国大丰麋鹿 (Elaphurusdavidianus) 4只母鹿的产仔行为进行了较为细致的观察和分析。结果表明 ,首次离群至分娩时间间隔的平均值为 32 2 5h ;母鹿临产时的行为主要有走动、卧地、回头顾腹、呆立、嗅地等 ,走动的频次最高 ,其次是卧地和回头顾腹 ;分娩历时平均为 33 75min ,以卧式分娩为主 ;仔鹿的首次站起时间为 39min ,仔鹿吃到初乳的时间为 6 0 75min。  相似文献   

7.
浅谈密植丰产桑园的栽培管理技术   总被引:1,自引:0,他引:1  
高产密植桑园是以合理密植为前提,规范栽植为基础,肥培管理为中心,桑叶丰产为目标的低干型快速丰产桑园。高产密植桑园是蚕桑生产上的主要栽培形式,其对蚕农快速地产生养蚕效益有着重要的作用。高产密植桑园的栽培管理技术主要有:选栽优良桑品种,科学规范地合理密植,适时养成低干树形,加强桑园的常规管理,做好桑树病虫害的防治等。  相似文献   

8.
几年前,在江西等地发生了一种以高热、皮肤发红和呼吸困难为主要病症的猪的一种烈性传染病,给当地养猪生产造成了很大的损失,后来此病开始蔓延到湖南、湖北、江浙等地,引起了养猪业者的巨大恐慌,由于本病以高热为主要特征,人们将其命名为“高热病”。该病发病到现在已经有好几年,几乎每年都有本病的报道,有的地方疫情仍未平息。有的地区仍大面积发生,并造成大量猪只死亡,眼看高温季节就要来临了,有必要对本病再一次从新认识,以便唤起养猪业者的重视!  相似文献   

9.
河西地区草地退化成因分析与对策   总被引:9,自引:3,他引:6  
马琦  李葆春 《草业科学》2005,22(11):17-19
采用系统工程方法,运用解释结构模型法对草地退化的几个主要问题进行了分析,结合系统进行综合评价和递阶划分,结果表明:5个因素中以气候变化与管理为主要诱因导致草地退化.为此有针对性地提出了草地退化治理对策与建议.  相似文献   

10.
黑龙江省东南部林区6种啮齿动物食性分析   总被引:1,自引:0,他引:1  
为了准确掌握黑龙江省东南部地区对农林危害比较严重的啮齿动物的食性及食物量,以便更好地、有针对性地灭鼠,从而为林业部门预防鼠害提供科学依据,于2010年3月—2011年1月通过实地考察,对捕获的鼠进行解剖,并结合实验室喂养进行食物量测定。结果表明,种子和浆果是树栖型种类啮齿动物的主要食物,约占70%左右;而地栖型种类啮齿动物的食物存在明显的季节性和地域性差异。  相似文献   

11.
如今动物园给野生动物注射药物时,依靠吹管和气枪来发射,但有时相当的不便。本实用新型涉及了一种用于远程注射器的发射装置,包括发射本体,所述发射本体包括托架、管体、端盖;所述托架上设置有支架,所述管体置于托架上,所述端盖位于支架的后侧,所述端盖的前侧设置有从后至前口径依次缩小的固定部,所述端盖的固定部向前穿过支架,管体的后端与对应口径的固定部连接;所述管体与托架在靠近前端的位置通过连接件连接。旨在为日后的应用做出贡献。  相似文献   

12.
重组牛皮蝇素A蛋白的免疫试验   总被引:3,自引:0,他引:3  
用由毕赤酵母表达的皮蝇素A(Hypdermin A,HA)蛋白分别免疫新西兰大白兔和牦牛,了解该蛋白免疫效果。用两种不同分子量的重组HA蛋白分别免疫新西兰大白兔1次和2次,ELISA测其抗体消长规律。结果表明,3周后抗体水平达到峰值,后缓慢下降。50KD蛋白免疫效果较30KD蛋白好,差异非常显著(P〈0.01)。用其中50KD的重组HA蛋白分别在7月和9月免疫自然感染牛皮蝇蛆病牦牛,观察感染率和感染强度,ELISA测其抗体消长规律。结果表明,7月免疫组与9月免疫组感染率分别为83.3%和36.3%(对照组为55.5%);平均感染强度分别为6.5和4.2(对照组为13.0),差异不显著(P〉0.05)。免疫后,抗体水平上升,3个月后缓慢下降。9月免疫组免疫效果较7月免疫组好,三组抗体水平差异非常显著(P〈0.01)。上述研究结果为防治牛皮蝇蛆病疫苗的深入研究和实践运用提供了参考依据。  相似文献   

13.
The thyroid glands of 31 chickens at the age of 17 to 24 months were investigated. Different methods of anatomical preparation, casts of vessels and scanning electron microscopy were used. The thyroid gland of birds is a paired organ. It is located on the ventral surface of the base of the neck within the thoracic inlet. The left thyroid gland is placed more cranially than the right one. Each thyroid gland is closely connected to the common carotid artery on the medial side, from which it is supplied and to the jugular vein on the lateral side. It is a reddish-brown organ and of lenticular profile. The gland measures on average 10 mm in length, 6 mm in width and 2 mm in thickness, and is covered by a thin connective tissue capsule which holds adipose cells. It seems that each thyroid follicle is surrounded by a net of capillaries. The investigation by scanning electron microscopy proved that the follicles are oval with a pyramidal top on each end. The cuboidal epithelium cells leave impressions in the colloid. Epithelium cells carry microvilli on the follicle side surface. Described seasonal changes of the thyroid gland in size and activity were able to be confirmed by the examination of the organ in July and December. In winter the follicular cells were higher and the follicles had a greater volume.  相似文献   

14.
The current challenges (increasing levels of integration in the biological sciences) facing the teaching of zoology and the structure of the zoology curriculum are explored herein. General context is provided and a more focused scrutiny of the situation in North America is presented. The changing emphases in more broadly‐based biological sciences programs in North America are outlined, and their influence on the role of zoology as part of fundamental biological training is considered. The longer term impact of such changes in emphasis on the teaching of zoology is discussed, and the central role that zoology can play in dealing with both science content and science education is advanced. Based upon a focal workshop on the future of the zoology curriculum in Canada, a perspective on the challenges facing curriculum evolution is provided. Extensive curriculum redesign is called for to ensure that zoology provides a broad‐scale integrative approach to the understanding of biodiversity in evolutionary, ecological and functional contexts. Barriers to, and drivers of change are identified and the need for collaborative approaches to curricular evolution is emphasized.  相似文献   

15.
In variance component quantitative trait loci (QTL) analysis, a mixed model is used to detect the most likely chromosome position of a QTL. The putative QTL is included as a random effect and a method is needed to estimate the QTL variance. The standard estimation method used is an iterative method based on the restricted maximum likelihood (REML). In this paper, we present a novel non-iterative variance component estimation method. This method is based on Henderson's method 3, but relaxes the condition of unbiasedness. Two similar estimators were compared, which were developed from two different partitions of the sum of squares in Henderson's method 3. The approach was compared with REML on data from a European wild boar × domestic pig intercross. A meat quality trait was studied on chromosome 6 where a functional gene was known to be located. Both partitions resulted in estimated QTL variances close to the REML estimates. From the non-iterative estimates, we could also compute good approximations of the likelihood ratio curve on the studied chromosome.  相似文献   

16.
The effects of dietary deficiency, including both malnutrition and deficiency of specific vitamins, on behavior is discussed with special emphasis on the growing kitten and puppy. The effect of caloric restriction on behavior is reviewed so that owners can be advised what to expect when their dog is placed on a reducing diet. The evidence for influence of dietary protein and tryptophan on canine aggression is presented. The effect of special diets on canine cognitive dysfunction is reviewed.  相似文献   

17.
The Delvo-P-test (Gist-brocades nr, Delft, The Netherlands) is based on biological detection of antibiotics in the milk. According to the procedure of the manufacture the test is suited for bulk milk processing factories. Problems arise when the test is used on milk samples of a single cow. Buffers, cells, bacteria, cell contents, and desinfection without using antibiotics may give false positive and false negative results. An error up to 44.8% was detected on single cow milk samples. The test is well suited for bulk milk, where the processing of milk follows a biological procedure as for cheese. The use on single cow milk samples to prove absence of antibiotics is not recommended.  相似文献   

18.
C.M. Mejdell   《Livestock Science》2006,103(3):292-296
The way production animals are treated is a matter of public concern, and public opinion is often a driving force to introduce new animal welfare legislation. In Norway, a Council on Animal Ethics has been appointed by the authorities since 1993. The composition of the council is broad and it encounters both lay people and experts. The council is independent and advisory, only. It shall be a “guard dog” and follow the developments in animal production and other areas where man makes use of animals, and give advice to the authorities on the need for change in legislation and administrative practices. An important task for the council is also to contribute to and facilitate an informed public debate on animal welfare standards and animal ethics.  相似文献   

19.
何家禄 《蚕业科学》1991,17(2):95-100
家蚕血液酯酶电泳图谱中A区酯酶缺失型东34,是共显性等位血液酯酶A区酶带不表达基因BesAo的纯合子,基因符号Bes Ao/Ao。东34是其亲本交配后代的分离,选择,固定后的产物。东34缺失的A区酶带属胆碱酯酶类。  相似文献   

20.
超数排卵是山羊胚胎移植技术中的关键环节,是胚胎移植所需胚胎的主要来源。山羊多采用以孕酮类阴道栓同期发情为基础的超数排卵方案,山羊超数排卵和胚胎移植的成功依赖于一套完善、成熟的技术体系,是一项严密的系统工程。掌握影响山羊超数排卵的因素非常重要,论文就不同激素、季节、年龄和重复超排等因素对山羊超排效果的影响做一综述。  相似文献   

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