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1.
利用SSR、ISSR和RAPD技术构建苜蓿基因组DNA指纹图谱   总被引:45,自引:13,他引:45  
魏臻武 《草业学报》2004,13(3):62-67
在建立可靠的苜蓿基因组DNA提取分离和PCR扩增技术体系的基础上,筛选具有稳定多态性位点的RAPD、SSR和ISSR引物,建立苜蓿基因组DNA的SSR、ISSR和RAPD分子标记技术体系,并利用分子标记检测苜蓿品种(系)的DNA分子标记多态性,构建苜蓿品种的DNA指纹图谱.筛选出36个RAPD引物,8个SSR引物和12个ISSR随机引物,通过PCR扩增在55个国内外苜蓿品种(系)中获得了182个RAPD多态性位点和丰富的SSR和ISSR多态性位点,构建了55个苜蓿品种(系)的SSR、ISSR和RAPD指纹图谱.结果表明,不同苜蓿品种(系)的SSR多态性有较大差异;苜蓿品种ISSR指纹图谱多态性丰富,稳定性比RAPD强;可以通过2~3个引物鉴别我国主要苜蓿品种和引进品种,SSR和ISSR指纹图谱可以更好地用于苜蓿品种鉴定和遗传多样性分析.  相似文献   

2.
采用ISSR和RAPD标记对8个60Co-γ辐射梯度诱变白刺花(Sophora viciifolia)进行遗传多样性分析。结果表明:20条ISSR和6条RAPD引物的PPL多态率分别为51.37%和21.03%,ISSR的Nei's指数和平均Shannon指数均大于RAPD;ISSR的标记指数(1.28)是RAPD(0.20)的6.4倍,表明ISSR具有较高的标记效率。Mantel检测表明,ISSR+RAPD标记与ISSR标记的结果显著相关(P<0.05)。综合分析表明白刺花用ISSR标记可检测出更高的多态性,更能准确反映白刺花材料间的遗传关系。  相似文献   

3.
李天芝 《养猪》2022,(6):95-96
<正>猪伪狂犬病(PR)是由伪狂犬病病毒(PRV)感染引起的一种急性、热性、高度接触性传染病[1]。各品种和日龄猪均可感染,母猪和仔猪危害严重,母猪主要表现为流产、死胎、木乃伊胎等繁殖障碍性疾病[2],仔猪则表现为神经症状、呕吐、腹泻及高死亡率;肥育猪常表现为呼吸道疾病,死亡率低,但可以隐性带毒,并不定期排毒[3]。该病在我国广泛流行,给我国养猪业造成了严重的经济损失[4]。世界动物卫生组织(OIE)将其列为B类传染病,我国将其列为二类动物传染病[5]。  相似文献   

4.
<正>在畜禽养殖中,要增加畜禽产量、提高饲料转化率、降低饲料成本,关键技术措施是配制营养平衡和完善的饲料[1]。目前饲料配方设计软件中使用的数学方法主要是线性规划[2]。线性规划在得出饲料配方的同时,还可以获得包括影子价格、灵敏度分析结果在内的很多其他信息[3]。但是线性规划本身还具有一定的缺陷[4~7],它无法妥善解决多目标优化问题。  相似文献   

5.
促进马蔺种子萌发的前处理方法探讨(简报)   总被引:3,自引:1,他引:2  
马蔺(Iris lacteaPall.var.chinensis(Fisch.)Koidz)别名马莲、马兰、马兰花,是鸢尾科鸢尾属多年生宿根草本植物,根、花、种子均可入药[1]。该种分布于内蒙古、宁夏、青海、西藏等20多个省区,生长于荒地路旁、山坡草丛、盐碱草甸中,耐盐碱,耐践踏,根系发达,可用于水土保持,盐碱地、工业废弃地改造和园林绿化等[2,3]。马蔺种子具有很深的休眠,在人工栽培过程中,存在着当年播种出苗率低的现象,次年出苗率也不足30%[4]。关于破除马蔺种子休眠的研究报道很多,但是最终发芽率均不高[5],或者虽然得到了较高萌发率,但需要时间较长[6],李苗等[5]通过物理、药剂以及低温层积处理的单一或综合处理方法处理马蔺种子,得到的最高发芽率为14%,郭瑛等[6]对马蔺自然萌发试验表明其种子播种经过10个月的发芽率才达到73%,李志武[4]等研究发现,拌雪埋藏30d可使马蔺种子的发芽率达到83%-87%,但该处理方法只在常年积雪的地区才具有实意义。为了有效地破除马蔺种子休眠,促进其迅速、整齐地萌发,本文比较了机械破除种皮、酸蚀、层积等处理效果,探索可促进马蔺种子萌发的前处理方法。  相似文献   

6.
结缕草冷处理后可溶性蛋白的变化(简报)   总被引:1,自引:0,他引:1  
结缕草属(Zoysia Willd.)为重要的暖季型草坪草属之一,很多优良特性[1]。对结缕草(Z.japonica)的抗寒性研究已有不少。Beard等[2]对35种暖季型草坪草的抗寒性研究表明,结缕草的抗寒性最强。Dunn[3]研究表明结缕草属植物耐寒性存在明显的种间差异,而且与抗寒锻炼有关。李亚等[4]采用改良电导法(EL)对中国54种代表性种质的抗寒性进行了研究。Gerloff[5]证明低温下苜蓿(Medicago sativaL.)的可溶性蛋白质增多。  相似文献   

7.
<正>牛传染性结膜炎是牛的一种急性传染病,可由多种病原引起[1]。目前大多数学者认为牛摩拉克氏杆菌是引起该病的主要病原体[2]。该病可通过虫媒传播,传染性极高,各品种和年龄的牛都可发病[3],一旦发病会引起牛食欲减退、消瘦,虽死亡率不高,但对养殖业危害极大[4]。现笔者对一起牛传染性结膜炎的诊治经过介绍如下。1 发病情况2022年10月中旬,某肉牛场牛眼部出现不适症状。刚开始,  相似文献   

8.
<正>近年来,全球蜜蜂面临多方面的挑战,出现大量死亡[1、2]。例如,复杂多样的疾病、农药的大量使用和生存环境的破坏等对全球蜜蜂造成重大威胁[3]。而在治疗蜜蜂各类疾病过程中,抗生素等药物仍然广泛使用,容易污染蜂产品,导致蜂产品销售受阻,给蜂农们带来了巨大损失[4,5]。  相似文献   

9.
28种苔草属植物种子发芽特性研究(简报)   总被引:5,自引:2,他引:3  
吉文丽  吉鑫淼  陈东燕  李卫忠 《草地学报》2009,17(6):834-836,840
莎草科苔草属(Carex)是世界上分布最广的属之一[1], 其适应性强、返青早、生长期长、根茎发达、耐践踏,既是理想的草坪草种,又是良好的牧草资源和环境保护植物[2,3]。但同时具有休眠严重、萌发困难等特点[4,5],使进一步开发利用受到严重制约。本研究以28 种苔草属植物种子为对象,探讨了苔草属植物种子对恒温和变温、湿沙层积和干藏的发芽响应。通过对苔草种子发芽特性的研究,不仅可以提高苔草种子发芽率,筛选发芽率高的苔草种类,也可以为种子发芽生态研究提供科学依据[6]。  相似文献   

10.
<正>胆结石来自凝结的胆囊沉积物[1]。胆色素、黏蛋白、细菌和返流的肠道内容物可作为结石微粒生成的病灶,随后可发展为大的结石[2]。胆结石在犬较为罕见,并且患犬极少表现出临床症状[1,2],可能出现的临床症状包括厌食、呕吐、昏睡、发热、腹部疼痛、腹泻、黄疸和色素尿[2,3]。笔者于2020年11月接诊1例因巨大胆结石及细菌性胆囊炎引发间歇性发热的病例,通过胆囊切除术治疗后恢复良好,报告如下。1 病例情况5岁雄性泰迪犬,已去势,  相似文献   

11.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

12.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

13.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

14.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

15.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

16.
17.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

18.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

19.
正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in  相似文献   

20.
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