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1.
对当地野生草种麦宾草进行了驯化栽培的初步研究。结果表明:麦宾草在海拔高度3 800m左右的果洛地区在栽培条件下能完成整个生育期生长,栽培当年高度可达到16.0cm,盖度达到60%,第2年株高可达到110cm,盖度达到96%;栽培当年干草产量为1 266.8kg/hm2,第2年、第3年和第4年的干草产量分别为7 959.4kg/hm2,6 462.4kg/hm2,5 244.1 kg/hm2,种子产量分别为1 000.2kg/hm2,880.6kg/hm2,790.5kg/hm2。该草种是适合三江源区黑土滩退化草地植被恢复与重建的优良草种,也是高寒草甸地区建植高质量的生态型或刈用型黑土滩人工草地的优良草种。  相似文献   

2.
以"川草2号"老芒麦(Elymus sibiricus L.cv.chuancaoNO.2)为试验材料,采用不同底肥、不同施肥量和不同行距等处理对"川草2号"老芒麦进行种子丰产栽培技术研究,以期为"川草2号"老芒麦种子生产管理技术提供依据。结果表明:复合肥作底肥施肥量为120 kg/hm2的平均种子产量最高,达1 612.26 kg/hm2,施肥量为120 kg/hm2比较适合老芒麦种子生产。施肥量过高,不但浪费资金投入,而且不利于"川草2号"老芒麦种子生产;复合肥作底肥行距为60 cm的种子产量最高,为1 534.5 kg/hm2,在红原进行"川草2号"老芒麦种子生产,行距60 cm比较适合。  相似文献   

3.
以"川草2号"老芒麦(Elymus sibiricus L.cv.chuancao NO.2)为试验材料,采用不同底肥、不同施肥量和不同行距等处理对"川草2号"老芒麦进行种子丰产栽培技术研究,以期为"川草2号"老芒麦种子生产管理技术提供依据.结果表明:复合肥作底肥施肥量为120 kg/hm2的平均种子产量最高,达1 612.26 kg/hm2,施肥量为120 kg/hm2比较适合老芒麦种子生产.施肥量过高.不但浪费资金投入,而且不利于"川草2号"老芒麦种子生产;复合肥作底肥行距为60 cm的种子产量最高,为1 534.5kg/hm2,在红原进行"川草2号"老芒麦种子生产,行距60 cm比较适合.  相似文献   

4.
皇竹草是多年生直立型丛生性耐刈割的禾本科牧草,在西昌市海拔1500m、1 760m、2000m地区年总产鲜草分别可达2.48×105kg/hm2、1.98×105kg/hm2、1.81×105kg/hm2,日平均生长高度分别为3.26 cm、3.00cm、2.85 cm,结果表明皇竹草产量高,适应性广,生长快,可在西昌市海拔1 500～2 000m范围内大面积推广种植.  相似文献   

5.
行距和肥力对川草2号老芒麦生产性能的作用   总被引：5，自引：1，他引：4  
在田间试验条件下,采用裂区设计方法,研究了不同追肥、不同行距和不同基肥对川草2号老芒麦Elymus sibiricus cv.chuancao No.2生产性能的影响.结果表明:分蘖-拔节期追施120kg/hm2复合肥可提高老芒麦生产性能;60cm行距时老芒麦种子产量最高达1 485kg/hm2,30 cm行距时老芒麦产量最高达10 70 kg/hm2;施180kg/hm2复合肥较施15t/hm2牛粪更有利于老芒麦种子生产.  相似文献   

6.
燕麦+箭筈豌豆混播草地的草层结构与产量   总被引：4，自引：1，他引：3  
在青藏高原高寒地区燕麦 +箭豌豆混播草层的茎主要分布在 0～ 3 0cm的高度 ,叶在 0～ 10 0cm ,花在 80～10 0。混播草层在前、中、后各生育期 ,均能保持较高的光合作用面积并可获得高产。依各项测定指标综合评定 ,燕麦 13 5kg/hm2 +箭豌豆 45kg/hm2 为适宜混播组合量 ,其干草产量比单播燕麦和箭豌豆分别增产 13 %和 96%。混播草层每元投资的经济收益均比燕麦、箭豌豆单播高  相似文献   

7.
在青海省铁卜加高寒地区,在不施肥、不灌溉和人工清除杂草的条件下,通过田间试验研究不同行距(20,30,40cm)和播种量(67.5,101.1和135kg/hm2)对野生扁穗冰草生长、种子产量和干草产量的影响,以确定最佳的扁穗冰草田建植条件。结果表明:不同播种因素处理对鲜重、株高、茎叶比及生长速度的影响不明显。但对草产量和种子产量的影响较大。其中,行距20cm,播种量67.5kg/hm2处理下的干草产量和种子产量均最大,分别为6 065.35和1 610.33kg/hm2。  相似文献   

8.
白茎盐生草对盐碱土壤的改良效果   总被引：2，自引：0，他引：2  
王文  张德罡 《草业科学》2011,28(6):902-904
摘要：在全盐含量0.49%的土壤中设置人工种植和自然生长白茎盐生草(Halogeton arachnoideus)处理,以裸地为对照,研究种植白茎盐生草对盐碱土壤的改良效果。结果表明,2个处理下的土壤全盐含量明显下降,0~20 cm土层分别下降28.57%和32.65%。对盐碱的消除效果0~20 cm土层较20~40 cm好。播种前0~20 cm土壤全盐总量约为11.172 t/hm2,1个生长季后下降为8.738 t/hm2,全盐总量下降2.434 t/hm2,即种植白茎盐生草1年可从0~20 cm土层中除去盐分2.434 t/hm2。试验前后,0~20 cm土壤pH值下降0.13～0.14,下降幅度大于20~40 cm土壤。白茎盐生草对盐分的富集降低了土壤的pH值,达到改良盐碱土壤的目的。  相似文献   

9.
不同放牧强度对三峡地区灌丛草地植物产量的影响   总被引：7，自引：2，他引：5  
研究了不同放牧强度下长江三峡地区灌丛草地植物产量的动态变化。结果表明 ,灌丛草地上的优势草本植物种是芒 ,重牧区灌丛草地中芒的地上生物量均显著 (P<0 .0 5 )小于对照和轻牧区。对照、轻牧和重牧 3种处理下 ,芒的平均地上生物量 (干物质 )分别为 (74 9.1± 80 8.7) kg/ hm2 、(6 98.6± 6 78.8) kg/ hm2 和 (2 2 2 .5± 10 0 .5 ) kg/ hm2 。在对照、轻牧和重牧处理下 ,灌丛草地禾草、灌木和杂类草的产量组成依次分别为 :3.7∶ 1.5∶ 1、5 .3∶ 1.6∶ 1、1.5∶ 1.2∶ 1,灌丛草地上禾草的产量动态变化趋势与总产草量的变化基本一致。9月份灌丛草地的产草量最高 ,对照、轻牧和重牧 3个处理的总产草量分别为 30 4 2 .8kg/ hm2 、2 5 18.4 kg/ hm2 和 1180 .3kg/ hm2 。  相似文献   

10.
本试验以老芒麦为研究对象,采用随机区组试验设计,研究了不同刈割高度对"川草2号"老芒麦牧草产量与品质的影响。试验结果表明:在盛花期不同刈割高度对"川草2号"老芒麦牧草产量与品质具有一定的影响。其中,以4cm刈割高度时的鲜草产量和干草产量最高,分别为22 029.95kg/hm2和5 755.94kg/hm2,但牧草品质较差,其CP为11%;6cm刈割高度时鲜草产量和干草产量相对较高,分别为20 207.32kg/hm2和4 781.259kg/hm2,但牧草品质最好,其CP达到15.73%。综合各项指标,"川草2号"老芒麦在盛花期,以刈割高度为6cm时,能使牧草产量与品质达到最佳。  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.
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   

13.
Tropical Animal Health and Production -  相似文献   

14.
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   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
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   

17.
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   

18.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

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