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1.
内蒙古赤峰市敖汉旗两大主要牧草品种敖汉苜蓿、沙打旺可以在退耕还草、防风治沙中发挥重要作用。敖汉旗全旗草地总面积24万hm^2,其中人工草地8.13万hm^2,每年可为我国畜牧业发展提供2亿kg的优质牧草和l000~1500t的优质牧草种子。该旗具备无霜期长、降水集中、热量丰富、雨热同期等良好的自然条件,十分适合发展人工种草和牧草种子生产。  相似文献   

2.
通过田间试验表明:沙打旺生育期177 d,从第2年开始能收少量种子;沙打旺由于花期长,种子成熟不一致,应适时收种;第1年有少量分枝,第2年分枝数12.6,第3年分枝数22.3;产草量高,第2年产草量22 000 kg/hm2,第3年产草量3 8000 kg/hm2,宜在花期以前刈割利用;沙打旺再生能力比苜蓿弱,二茬草高度只有46 cm;沙打旺根系发达,抗旱、抗寒、耐瘠薄、竞争力强,能形成单一郁闭群落。沙打旺为中等耐盐植物,耕作层土壤含盐量在0.655%以下时,植株生长正常,达到0.836%时,植株生长受到抑制,达到0.96%时,种子不能发芽。  相似文献   

3.
紫花苜蓿和沙打旺包衣配方研究   总被引:1,自引:0,他引:1  
在实验室内利用种子丸衣化技术处理2种豆科牧草在土壤含水量较低的砂土上做盆栽试验。试验证明,利用硅藻土作填料的包衣配方,在干旱条件下萌发后能够提高丸衣化牧草种子的出苗率。试验结果表明,配方中含5%和2%吸水剂的紫花苜蓿Medicago sativa和沙打旺Astragalus adsurgens种子发芽时间均比对照提前2~4 d,配方中含5%吸水剂的紫花苜蓿和沙打旺种子出苗率均高于对照,紫花苜蓿增加50%,沙打旺增加37%。配方中含5%吸水剂的包衣种子出苗率最高,而含2%吸水剂的包衣种子配方最实用。  相似文献   

4.
杂花沙打旺(Astragalns adsurgens Pall.cv.Zahua)是全国牧草品种审定委员会审定登记的牧草品种。该品种是在早熟沙打旺基础上育成的,具有抗旱、抗寒、对土壤要求不严、早熟和产量稳定等特性。为了获得优质高产的种子,我们在呼市地区进行了大面积生产试验,旨在组装配套出杂花沙打旺种子生产过程的优化技术模式。  相似文献   

5.
<正> 大多数优良牧草的种子很小,一般播种深度为0.6~2.0厘米。种子周围土壤的含水量是影响出苗的一个决定性因素。在发芽和出苗期,牧草种子必须在湿土中保持若干天。但上部2厘米土层仅在一天内便干到凋萎点。因此加快种子发芽和出苗过程,可促进牧草建植。本项研究的目的是确定:(a)催芽牧草种子的出苗是否比未处理(干种)的多;(b)保证成功的催芽程度;(c)因受旱未出苗的种子再灌水是否还会出苗?  相似文献   

6.
沙打旺     
沙打旺又叫直立黄芪、麻豆秧、薄地强、苦草、地丁等。沙打旺栽培种原产于我国的黄河故道地区,即江苏北部和山东、河南、河北的部分地区,其野生种斜茎黄芪在我国的东北、华北、西北和西南地区均有分布。 (一)特征特性 沙打旺为豆科黄芪属多年生草本植物,株高10~20米,全株被丁字形茸毛,主根粗而长,侧根较多,主要分布在20~30厘  相似文献   

7.
15沙打旺--用于治理沙化土地 沙打旺是豆科多年生优质牧草,又名直立黄芪.株高50~110厘米,适应性强,耐寒、耐贫瘠、耐盐、抗旱、抗风沙的能力强.在寸草不生的瘠薄地上,它能生长出强大的根系,长出很茂盛的茎叶.固沙能力特强,在播种当年,只要抓住苗不被风沙压住,就能正常生长,第二年除流动沙丘外,风刮不走,沙压不住,是改良荒山和固沙的优良牧草.  相似文献   

8.
对不同盐胁迫条件下沙打旺种子的发芽率、发芽指数及幼苗根芽生长量等指标进行观测分析,探讨了盐胁迫影响种子萌发的因为.结果表明,随盐浓度升高,沙打旺种子发芽时间推后,发芽率降低,耐盐半致死浓度为235.25 mol/L,耐盐极限浓度为469.66 mol/L;低盐浓度胁迫在不同程度上可促进沙打旺种子的萌发.  相似文献   

9.
几种牧草种子发芽方法的试验研究   总被引:1,自引:0,他引:1  
张木兰 《内蒙古草业》2005,17(3):25-26,40
通过对几种牧草种子发芽方法的试验研究,找到了使种子发芽理想的处理方法。试验结果表明,新收获的披碱草、老芒麦种子采用0.2%硝酸钾溶液预冷处理,不但发芽理想,发芽势也高。采用0.2%硝酸钾溶液预冷处理的羊草种子发芽率比未处理的发芽率提高了50%左右。因此,温度在20~30℃条件下,羊草种子和新收获的披碱草、老芒麦种子采用0.2%硝酸钾溶液预冷处理的发芽方法较为理想,而小粒豆科牧草种子采用砂擦法处理发芽较好。  相似文献   

10.
沙打旺和白沙蒿种子萌发检验标准化的研究   总被引:1,自引:0,他引:1  
李青丰  易津 《草地学报》1994,2(2):43-48
萌发力是种子检验的重要内容。统一检验标准程序和方法是保证检验结果公正、可靠的前提之一。本文选择《国际种子检验规程》和我国《牧草种子检验规程》中尚待修正或未曾涉及的沙打旺和白沙蒿两种优良牧草进行种子萌发检验标准化的研究。探讨光、温度和发芽床三种因素对种子发芽的影响。温度设15℃、20℃、25℃、30℃恒温和(25/15)℃、(3/20)℃变温共6个处理;光设光照和黑暗两处理;发芽床设纸上、纸间、沙上、沙中4个处理。首先以纸上为发芽床,选择最佳温度、光照条件及其最优组合,其次探索最适发芽床。同时结合观察种苗发育过程进行断土根实验,以确定幼苗鉴定标准和初次计数与末次计数时间。  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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