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1.
以扁蓿豆3个品系的下胚轴和子叶为外植体,研究不同培养基、不同激素种类和配比对愈伤组织诱导的影响,以及不同分化培养基对愈伤组织分化的影响。结果表明:下胚轴的愈伤组织诱导率普遍高于子叶;品系B1、B2最佳愈伤组织诱导培养基为MS--0.5mg/L2,4--D+O.5mg/L6--BA,品系B3最佳愈伤组织诱导培养基为MS+0.5mg/L2,4--D+0.7mg/L 6-BA;适宜分化的培养基均为MS+1mg/L KT+1mg/L6-BA。  相似文献   

2.
应用正交设计优化紫花苜蓿愈伤组织诱导的激素配比   总被引:5,自引:2,他引:3  
以MS+2,4-D(2.0mg/L)为基本培养基,附加NAA、6-BA和KT3种植物激素,采用正交试验设计法研究不同浓度激素配比对和田苜蓿,秘鲁苜蓿和甘农3号苜蓿下胚轴愈伤组织诱导的影响。结果表明:对于秘鲁苜蓿和甘农3号苜蓿,最适愈伤组织诱导的培养基均为MS+2,4-D(2.0mg/L)+6-BA(0.5mg/L)+NAA(1.0mg/L),各因素影响程度为6-BA〉NAA〉KT。对于和田苜蓿,最适愈伤组织诱导的培养基为MS+2,4-D(2.0mg/L)+6-BA(1.0mg/L)+KT(1.0mg/L)+NAA(1.0mg/L),各因素影响程度为6-BA〉KT〉NAA。  相似文献   

3.
刘芳  王玉祥  陈爱萍  张博 《草地学报》2012,20(4):741-746
以新疆野生黄花苜蓿(Medicago falcata L.)为材料,通过愈伤组织诱导及分化途径获得再生植株;从种子硬实、外植体、激素(2,4-D和KT)、培养基方面探讨野生黄花苜蓿组织培养的影响因素.结果表明:4℃低温处理与浓硫酸浸种结合是破除黄花苜蓿硬实的较优方法,发芽率达90%;下胚轴为诱导愈伤组织的最佳外植体;MS培养基比改良的SH培养基对愈伤组织的诱导更有效,MS诱导培养基为MS+2,4-D 0.5 mg·L-1+KT 0.8 mg·L-1+蔗糖30 g·L-1+琼脂粉7g·L-1,出愈率达到80%;浅绿色和浅黄色的愈伤组织在MS+2,4-D 0.2 mg·L-1+KT 0.4mg·L-1+CH 1 g·L-1+蔗糖20g·L -1+琼脂粉7 g·L -1的培养基上分化较好,分化率为30%.研究结果将为黄花苜蓿生物技术育种奠定一定的基础.  相似文献   

4.
以小花碱茅成熟种子为外植体,研究了脱颖处理和不同激素配比对愈伤组织诱导和分化的影响,成功建立了其组织培养植株再生体系。结果表明,种子脱颖处理显著提高了种子发芽率,降低了污染率;诱导愈伤组织的最佳培养基为添加5.0 mg/L 2,4-D 的 MS 培养基,诱导率可达55.2%,2周可见白色愈伤组织;最佳芽分化培养基为添加1.0 mg/L 6-BA 和0.5 mg/L NAA 的 MS 培养基,分化率可达31.7%,同时伴随根毛的发生,生根率达81.7%,诱导时间为2周;分化后的再生苗移植于1/2MS 培养基上,100%生根,炼苗移栽后可全部成活。从小花碱茅种子诱导愈伤组织到植株再生共需16周左右。小花碱茅组织培养植株再生体系的建立为进一步探究小花碱茅耐盐碱分子机制奠定了基础。  相似文献   

5.
本研究以山丹新麦草成熟种子为材料,进行了组织培养再生体系的研究。通过研究和筛选新麦草离体成熟胚愈伤组织诱导培养、继代增殖和分化培养的最佳激素配比,建立了从愈伤组织到再生小植株的再生体系。结果表明:成熟胚愈伤组织诱导的最佳激素配比是MS+2.4-D2.0mg/L。出愈率为91.7%。继代增殖培养的最佳激素配比是MS+2.4-D1.5mg/L+KT0.5mg/L。愈伤组织平均日增重1.43%。分化培养的最佳激素配比是MS+2.4-D2.0mg/L+NAA1.0mg/L。其绿色芽点率和出苗率分别为78.5%和49.5%,白化苗率为2.5%。  相似文献   

6.
以野生天蓝苜蓿种子发育5~7d无菌苗的子叶、下胚轴和种子苗叶片为外植体,对其愈伤组织诱导及其分化的基本培齐与外源激素组合和浓度配比进行试验。结果表明:对子叶、下胚轴和叶片愈伤组织诱导最适宜的基础培养基分别是MS、B5和SH;激素的种类及其浓度配比对于愈伤组织的诱导因不同的外植体有很大的差异。其中,子叶、下胚轴以MS+NAA(0.5~1.0mg/L)+6-BA(0.7mg/L)效果较好,叶片以SH+NAA(0.5—1.0mg/L)+2,4-D(1.5~5mg/L)十6胡A(0.7mg/L)较好,少量下胚轴在MS+NAA(0.5mg/L)+6-BA(0.7mg/L)和MS+NAA(0.5mg/L)+KT(0.5mg/L)的培养基中直接分化出胚状体,并成功发育成植株。在培养基Whb5上,子叶、下胚轴和叶片的分化都得到了很好的效果,分化率分别为43%、57%、40%,15~30d后都能再生植株。  相似文献   

7.
苜蓿花药培养及倍性鉴定   总被引:6,自引:3,他引:3  
在不同低温预处理时间,不同培养基和不同激素组合下进行了苜蓿花药培养实验。结果表明,花药4℃低温预处理24h、48h较72h诱导效果好。NB培养基对愈伤组织的诱导效果比战培养基好。最佳愈伤组织诱导培养基组合为NB+2,4-D0.5mg/L+NAA0.3mg/L+6-BA0.5mg/L+KT3.0mg/L。通过不同蔗糖浓度对愈伤组织的诱导效果比较,表明低浓度的蔗糖有利于降低愈伤组织的褐化率,高浓度的蔗糖有利于单倍体愈伤组织的诱导。分化培养的最佳组合为MS+NAA0.2mg/L+6-BA3.0mg/L。诱导生根最好的培养基为1/2MS培养基,最适合蔗糖浓度为10g/L。  相似文献   

8.
植物激素对2个紫花苜蓿品种再生体系的影响   总被引:2,自引:2,他引:0  
采用MS为基本培养基,附加不同浓度的2,4-D、KT和NAA,对"盛世"和"甘农4号"2个紫花苜蓿品种进行了组织培养再生体系的研究。结果表明:下胚轴是愈伤组织诱导的最佳外植体材料;2,4-D浓度增加对"甘农4号"紫花苜蓿出愈率影响不明显,但"盛世"紫花苜蓿的出愈率随着2,4-D浓度的增加呈显著升高趋势;2个品种的最佳愈伤组织诱导培养基为MS+2 mg/L 2,4-D+0.3 mg/L KT+30g/L蔗糖+7.5 g/L琼脂;最适分化培养基为MS+KT0.5 mg/L+NAA0.1 mg/L+蔗糖20 g/L;最佳诱导生根的培养基为1/2 MS+NAA0.5 mg/L。  相似文献   

9.
草地早熟禾愈伤组织诱导及植株再生   总被引:3,自引:0,他引:3  
以成熟种子和胚轴为外植体诱导草地早熟禾愈伤组织,比较草地早熟禾四个品种的愈伤诱导情况和不同6-BA浓度、愈伤年龄等因素对愈伤组织分化能力的影响。结果表明:成熟种子的出愈率与胚性愈伤诱导率均高于胚轴;MS 2,4-D(2mg/L) 6-BA(0.1mg/L)培养基为草地早熟禾Mardona品种较为合适的愈伤培养基,其诱导率为58,3%;MS BA(3mg/L) KT(0.2mg/L)为较为适合的分化培养基。再生率高达70%;随着继代次数的增加,草地早熟禾分化能力能够继续保持。选择致密、易碎、生长迅速的愈伤继代能够保持草地早熟禾的胚性。可以为遗传转化提供长期良好的植物材料。  相似文献   

10.
以海滨雀稗(Paspalum vaginatum cv.Sea spray)的成熟种子为外植体,运用正交试验设计,在MS基础培养基上添加不同浓度的2,4-D、6-BA、NAA、KT、CuSO4、AHC等外源物质,分析其对愈伤组织诱导、胚性愈伤组织分化的影响,建立海滨雀稗高频再生体系,为基因工程育种奠定基础.试验结果表明,在MS培养基中添加2.0 mg/L 2,4-D和0.5g/L AHC 能提高种子的发芽率至97.50%;最佳胚性愈伤诱导培养基为:MS +2,4-D 3.0mg/L+CuSO4 15.0 mg/L+AHC 1.0g/L,其胚性出愈率为66.88%;最佳分化培养基为:MS+6-BA 8.0mg/L+KT 0.05 mg/L+CuSO4 10.0 mg/L+NAA 0.5 mg/L,其分化率为95.00%.  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
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   

13.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

14.
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   

15.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

16.
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   

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19.
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   

20.
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   

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