铁线莲‘Blekitny Aniol’组织培养及再生体系建立

对铁线莲(Clematis florida‘Blekitny Aniol’)的带芽茎段进行诱导产生无菌苗,并对其叶片和茎段进行愈伤组织诱导成苗的分化研究,成功建立了铁线莲组织培养再生体系。结果表明,带芽茎段诱导腋芽最佳培养基为MS+1mg·L~(-1)6-BA+0.05 mg·L~(-1)NAA,腋芽萌发率为100.0%;茎段诱导愈伤最适宜培养基为MS+2 mg·L~(-1)6-BA+0.01mg·L~(-1)NAA,诱导率为78.3%;叶片诱导愈伤组织最适宜的培养基为MS+1 mg·L~(-1)6-BA+0.1 mg·L~(-1)NAA,诱导率为81.7%;愈伤组织分化的最佳培养基为1/2MS+1 mg·L~(-1)6-BA+0.05 mg·L~(-1)NAA,分化率可达25.0%;最适宜不定芽的增殖培养基为1/2MS+3 mg·L~(-1)6-BA+0.1 mg·L~(-1)NAA,增殖倍数为4.94;筛选出最优的生根培养基组合为1/2MS+0.05 mg·L~(-1)NAA,生根率为70.2%。本研究将为铁线莲的推广应用提供参考,也为其他铁线莲属植物引种和开发利用奠定了基础。     

扁穗牛鞭草再生体系的建立

以‘雅安'扁穗牛鞭草(Hemarthria compressa)的幼茎和幼叶为外植体,通过胚性愈伤组织建立扁穗牛鞭草的高效再生体系。结果表明:幼叶比幼茎更适合建立再生体系,最佳诱导培养基为MS+2,4-D 1.0 mg·L~(-1),幼叶和幼茎的出愈率分别为100%和86.96%。最佳分化培养基和不定芽增殖培养基均是MS+6-BA 1.0 mg·L~(-1)+NAA 0.2 mg·L~(-1),愈伤分化率分别为100%和72.90%,再生苗增殖系数可达18.6。1/2 MS是最适宜的生根培养基,生根率达100%。     

大花红景天外植体筛选及愈伤组织诱导研究

以大花红景天种子为材料进行无菌苗培养,筛选和优化最佳外植体和愈伤组织诱导培养基,为大花红景天快速繁殖提供理论依据。大花红景天无菌苗培养基为1/2MS,pH5.4,置于湿度75±2%,光照强度2 000lx,光照12h(20±1℃)∶黑暗12h(10℃±1℃)环境中培养;最佳外植体为根颈顶端组织;愈伤组织形成最佳培养基为MS+1.5mg·L~(-1) 2,4-二氯苯氧乙酸(2,4-D),1.5mg·L~(-1 )6-苄氨基嘌呤(6-BA),0.5mg·L~(-1)6-糠基氨基嘌呤(KT),0.2mg·L~(-1)吲哚-3-乙酸(IAA),置于湿度75±2%,光照强度2 000lx,光照8h(20±1℃)∶黑暗16h(10±1℃)环境中培养,出愈率最高可达95%。本试验获得大花红景天最佳的无菌苗培养条件,根颈顶端组织最佳外植体,优化愈伤组织诱导培养基,提高了诱导率,适宜在低海拔条件下进行快速诱导大花红景天的愈伤组织和植株再生,为大花红景天快速繁殖和规模化生产提供了依据。     

多花黑麦草特高和多年生黑麦草四季高频组培再生体系的优化与建立

对在贵州地区广泛种植的多花黑麦草特高(Lolium multiflorum‘Tetragold’)和多年生黑麦草四季(L.perenne‘Four seasons’)的成熟种子进行了愈伤组织诱导及植株再生的研究,建立了两个品种的胚性愈伤组织高频诱导与再生体系。结果表明,剥去成熟种子的颖壳,切除1/3胚乳端,将特高接种于CC+7mg·L~(-1) 2,4-D+0.5mg·L~(-1) 6-BA、四季接种于CC+5mg·L~(-1) 2,4-D+0.5 mg·L~(-1) 6-BA的培养基中,在明显降低组培污染率的同时,能分别得到65.52%和63.55%的最高愈伤组织诱导率;将两个品种诱导出的愈伤组织转移在MS+0.5 mg·L~(-1) 2,4-D+0.5mg·L~(-1) 6-BA+1.25mg·L~(-1) CuSO4+1.0g·L~(-1) CH的继代培养基上,能促进质量较好的Ⅱ型胚性愈伤组织的形成;根据后续转化试验所选用的植物表达载体pCAMBIA 1300的抗性特点,30~40mg·L~(-1)的潮霉素是两个品种愈伤组织最佳的筛选剂和临界浓度;特高的胚性愈伤组织接种在MS+2.0 mg·L~(-1) 6-BA+0.5 mg·L~(-1) NAA+0.1mg·L~(-1) TDZ的培养基上,可以产生86.37%的最高分化率,四季的胚性愈伤组织接种在MS+6.0 mg·L~(-1) 6-BA+0.3mg·L~(-1) NAA+5.0mg·L~(-1) KT的培养基上,能得到85.40%的最高分化率;生根培养基1/2MS+0.5 mg·L~(-1)NAA+0.5mg·L~(-1) IAA能让两个品种分化出的不定芽形成100%的生根率;以腐殖土∶蛭石∶砂壤土=1∶1∶1的混合材料作为营养土,能保证组培再生苗达到99%以上的成活率。优化建立的高频组培再生体系为下一步的遗传转化奠定了基础。     

芦竹属新材料绿洲3号的愈伤组织诱导

为了诱导愈伤组织,本研究以绿洲3号(Arundo)为试验材料,分别以NaClO(商品名为安替福民)和HgCl2(升汞)对其茎段进行消毒,然后取无菌茎段及从无菌茎段长出来的幼芽和幼叶为外植体,利用不同浓度的激素及1.0g·L~(-1)聚乙烯吡咯烷酮对外植体进行愈伤组织诱导。结果表明,以0.1%HgCl_2溶液消毒18min的消毒效果最佳,污染率为13%;而NaClO不能有效地消毒,且对茎段有一定的毒害作用。以MS+0.5 mg·L~(-1) 6-BA+1.0g·L~(-1) PVP+3.0mg·L~(-1) 2,4-D培养基配方的诱导效果最佳,且3种外植体中愈伤组织最难诱导的为幼叶,其次是茎段,最易诱导的为幼芽。其中,1.0g·L~(-1) PVP能显著促进芽诱导率,使得出愈率达到100%。     

火龙果愈伤组织诱导及再生体系的建立

为建立稳定、快速、高效的火龙果再生体系,以金都1号火龙果不同成熟度的茎段为外植体,探讨不同激素浓度配比、培养条件等对其愈伤组织及不定芽发生的影响。结果表明: 幼芽茎段和幼嫩茎段较适宜作为火龙果的诱导外植体。诱导率明显高于成熟茎段的诱导率。幼嫩茎段诱导愈伤组织最适合的培养基是MS +TDZ 0.6 mg/L + KT 0.8 mg/L +2,4-D 1.0 mg/L,诱导率是81.7%,不定芽再生率达到36%,幼芽茎段诱导的愈伤组织培养基为MS +6BA2.0mg/L +2,4-D 1.0 mg/L,诱导率高达91.7% 愈伤组织诱导不定芽的培养基为MS+NAA 0.2mg/L+6-BA 2.0 mg/L,生根诱导最适培养基为MS+6-BA1.0mg/L     

黄花苜蓿花药培养再生体系的建立与单倍体鉴定

花药组织培养再生体系的构建是单倍体育种的重要途径之一。本研究对呼伦贝尔黄花苜蓿(Medicago falcate‘Hulunbeier’)进行了花药组织培养研究并建立了花药组培再生体系。结果显示,液体悬浮培养基比固体培养基更适合呼伦贝尔黄花苜蓿花药愈伤组织的培养,其愈伤形成的培养条件为B5培养基+0.5 mg·L~(-1) 2,4-D+0.25 mg·L~(-1) 6-BA+0.4mg·L~(-1) NAA+3.0mg·L~(-1) KT;分化培养基为MS+1.0mg·L~(-1) 2,4-D+0.5mg·L~(-1) 6-BA+2%蔗糖+0.7%琼脂;生根培养基为1/2MS+0.1mg·L~(-1) NAA+2%蔗糖+0.7%琼脂;获得的再生植株经流式细胞仪鉴定,其单倍体比例高达27%。     

唐古特白刺组织培养及其培养基筛选研究

本试验选用唐古特白刺幼嫩茎段和叶片作为材料,研究白刺不同外植体的离体培养技术及其适宜的培养基。结果表明,白刺带芽嫩茎是诱导丛生芽的良好外植体,恒温20℃以下,可有效降低白刺丛生芽初代培养污染严重的程度;叶片是诱导愈伤组织的良好外植体,且低浓度生长素2,4-D培养基较高浓度培养基形成的白刺愈伤组织致密,也不易褐化。白刺的最适增殖、壮芽培养基为MS+6-BA 2 mg/L+NAA 1.00 mg/L,而且是以腋芽形成丛生芽的方式进行增殖的;最适生根培养基是1/2 MS+KT 1 mg/L+IBA 0.5 mg/L;形成愈伤组织较好的培养基是MS+2,4-D 0.5～1.0 mg/L。     

地被菊‘紫妍’和‘纽9722’的再生体系建立

本研究以地被菊(Chrysanthemum morifolium)两个品种‘紫妍’和‘纽9722’带腋芽的无菌茎段为外植体,在基本培养基中添加不同浓度的6-BA和NAA诱导叶片分化、茎段增殖以及继代生根,进行两个品种的再生体系建立。结果表明,利用2%NaClO对‘紫妍’和‘纽9722’适宜消毒时间分别为6、8min;诱导‘紫妍’叶片不定芽再生的最适培养基是MS+6-BA 2.0mg·L-1+NAA 1.0mg·L-1,愈伤组织诱导率为100%,分化率为92.22%,出芽数为7.60;‘纽9722’叶片不定芽再生的最适培养基是MS+6-BA 2.0mg·L-1+NAA 0.5mg·L-1,愈伤组织诱导率为100%,但分化率仅为45.59%;‘纽9722’茎段增殖的最适培养基是MS+6-BA 2.0 mg·L-1+NAA 0.5mg·L-1,增殖系数高达10.05;‘紫妍’生根的最适培养基是1/2 MS+NAA 0.2 mg·L-1,生根率为100%,生根系数为15.50;‘纽9722’生根的最适培养基为1/2 MS+NAA 0.3mg·L-1,生根率为100%,生根系数为14.87,移栽成活率均为100%。     

芡欧鼠尾草的组织培养和快速繁殖

以芡欧鼠尾草(Salvia hispanica)成熟种子为外植体,1/2MS为基本培养基,研究不同浓度的外源激素对愈伤组织的诱导、增殖和生根的影响,从而初步建立了芡欧鼠尾草组织培养的快速繁殖体系。结果表明,诱导种子愈伤组织的最适宜培养基为1/2MS+10.0mg·L~(-1) 6-BA+1.0mg·L~(-1) NAA+0.4mg·L~(-1) ZT,诱导率为66.5%;不定芽增殖的最适培养基为1/2MS+3.0mg·L~(-1) 6-BA+0.5mg·L~(-1) NAA,增殖倍数为7.69;生根的最适培养基为1/2MS+0.5mg·L~(-1) NAA,生根率达100%,平均生根数为5.68;移栽后植株生长良好,成活率较高,达97%。     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

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.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

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.     

Prevalence of gastric lesions in racing Alaskan sled dogs

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.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

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.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

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.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

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.     

Serum biochemical values and mineral element contents of tissues in yaks

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     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

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     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -