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1.
梭椤草的引种栽培试验   总被引：3，自引：3，他引：0  
野生梭椤草（Kengyilia thoroldiana）在海拔高度3756m的大武地区“黑土型”退化草地上通过2年的栽培和生长特性观测，结果表明：梭椤草越冬率可达到95％以上，第2年20％的植株在8月5日腊熟，鲜草产量615g／m^2，干草产量175g／m^2，茎叶比1：0．74。在高寒草甸的“黑土型”退化草地上也表现出较好的适应能力。  相似文献   

2.
对引入达日县和玛沁县“黑土型”退化草地的三种披碱草属牧草的生长情况,分别进行了4年和3年的观测。结果表明,这些牧草的越冬率均接近100%,抗寒性很强,适应性随栽培年限延长而提高。总的生长发育规律是生长前期地上植物增加速度较快,到抽穗期达到最大值,后逐渐下降。生育期随栽培年限延长而缩短,随海拔增高而延长。三种牧草第2年单位面积平均干草产量约1 100g/m2,垂穗披碱草和短芒老芒麦单位面积平均种子产量约330g/m2。是“黑土型”退化草地上建植人工植被的优良草种。  相似文献   

3.
通过对果洛州玛沁县野生草种藏异燕麦进行驯化栽培的初步研究,结果表明:藏异燕麦在海拔高度3800m的果洛地区人工栽培条件下表现出了较好的生态性能和栽培性能,第2年起能完成整个生育期,生育天数为125天;栽培当年生长缓慢,第2年起生长迅速,第3年长势达到高峰,株高可达78.6cm,盖度达到98.0%,越冬率达到99.0%,干草产量和种子产量分别为4268.1kg/hm^2和425.3kg/hm^2;第2年至第5年的平均干草产量和种子产量分别为3680.7kg/hm^2和368.7kg/hm^2。藏异燕麦叶量丰富,适口性好,适合刈牧兼用,喜潮湿地带生长,可作为高寒草甸退化草地植被恢复与重建的优良草种和先锋草种。  相似文献   

4.
在青南牧区“黑土型”退化草地上引种10个早熟禾品种,波伐早熟禾、青海扁茎早熟禾、冷地早熟禾、草地早熟禾、高山早熟禾、高寒肯塔基早熟禾和草地早熟禾巴林、康尼、肯塔基、超优异,通过3年的观测,除波伐早熟禾、青海扁茎早熟禾、冷地早熟禾和草地早熟禾4个品种能适应本区高寒气候,越冬率达80%以上,其余6个品种越冬率差,不能适应本区高寒气候。波伐早熟禾、青海扁茎早熟禾、冷地早熟禾、草地早熟禾4个品种第2年开始能完成完整的生殖生长,并在第2、3年产草量最高,第2年达到种子产量高峰。综合评比,波伐早熟禾、冷地早熟禾、草地早熟禾适应性好,产量较高,可作为本区“黑土型”退化草地植被恢复适宜的草种。  相似文献   

5.
羊茅属8种牧草在"黑土型"退化草地上的适应性表现   总被引：4，自引：0，他引：4  
在青海省达日县和玛沁县“黑土型”退化草地上引种的羊茅属8种牧草中有4个可安全越冬,抗寒性强,适应性随栽培年限延长而提高。其中,中华羊茅第2年开始生长发育即达完整,第2、第3年单位面积草产量接近1000g／m^2,种子产量高。下繁草毛稃羊茅、西北羊茅和紫羊茅（同德）第2年生殖枝占20％～35％,生殖生长不整齐,第3年开始产量大幅度增加,适应性增强。越冬良好的4种牧草对“黑土型”退化草地的适应性较强。  相似文献   

6.
草地早熟禾(Poa pratensis)栽培驯化研究初报   总被引：16，自引：4，他引：12  
通过营养体移栽和种子繁殖两种途径，对当地野生草种草地早熟禾进行了驯化栽培的初步研究，试验结果表明：草地早熟禾在海拔高度4000m左右的果洛地区在栽培条件下能完成整个生育期生长，栽培第2年株高可达到70cm以上，第2年和第3年的干草产量分别为626kg/hm^2和5692kg/hm^2，种子产量分别为690kg/hm^2和645kg/hm^2。具有发达的根茎繁殖能力，草地早熟禾既能进行种子繁殖也能进行根茎无性繁殖，是适合三江源区“黑土型”退化草地植被恢复与重建的优良种，也是在高寒草甸地区建植高质量的打草或放牧人工草地的优良草种。  相似文献   

7.
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   

8.
对果洛州玛沁县野生草种发草进行了驯化栽培的初步研究,结果表明∶发草在海拔高度3800m左右的果洛地区人工栽培条件下第2年起能完成整个生育期,生育天数为130d;栽培当年生长缓慢,第2年起生长迅速,第3年长势达到高峰,株高可达81.6cm,盖度达到98.0%,越冬率达到99.0%,干草产量和种子产量分别为4426.2kg/hm^2和482.8 kg/hm^2,表现出了良好的生态性能和栽培性能;发草叶量丰富,适口性好,适合刈牧兼用,喜潮湿地带生长,可作为高寒草甸(尤其是高寒沼泽草甸)退化草地植被恢复与重建的优良草种和先锋草种。  相似文献   

9.
气象影响因子对高寒针茅草原牧草产量的影响   总被引：6，自引：2，他引：4  
根据青海省兴海县1999-2009年高寒针茅草原西北针茅(Stipa sareptanavar.krylovii)生育期的气象资料和牧草年产量,对其11年的牧草产量数据进行五次多项式趋势产量拟合,计算气象产量和相对气象产量,利用DPS统计软件对牧草生育期内不同时段气候因子与相对气象产量的相关性进行分析,结果表明:8月下旬平均气温、积温对西北针茅产量的影响最大(P0.05);4月下旬的降水量,5月上旬10 cm地温,6月上旬平均气温、积温、5和10 cm地温以及8月下旬10 cm地温对西北针茅的影响次之(P0.10)。西北针茅生育期各气象因子与相对气象产量的多元线性逐步回归分析表明,6月上旬、8月下旬的平均气温,4月中旬、6月上旬的积温和5月下旬的降水量与西北针茅相对气象产量呈极显著负相关,各要素每增加1个单位,相对气象产量分别减少8.15、11.65、0.43、0.55、0.33 kg/hm2;7月上旬的积温、4月中下旬和6月下旬的日照时数与西北针茅相对气象产量呈极显著的正相关,各要素每增加1个单位,相对气象产量分别增加1.300 0、0.074 50、.785 0和0.137 0 kg/hm2。  相似文献   

10.
大武地区"黑土型"退化草地人工植被群落稳定性研究   总被引：3，自引：2，他引：3  
通过对大武地区在“黑土型”退化草地上建立的3龄和7龄单播垂穗披碱草人工草地的群落结构和植物量组成的研究,分析了“黑土型”退化草地人工植被的稳定性。研究结果表明:在人工调控管理下,3龄和7龄垂穗披碱草单播人工草地的群落组成仍然以垂穗披碱草为优势建群种,3龄和7龄单播人工草地地上植物量为377.4g/m2和371.2g/m2差异不显著,而显著高于“黑土型”退化草地250.1g/m2的水平。地上植物量组成中人工草地的优良牧草比例高达99%以上,而“黑土型”退化草地毒杂草比例占到了98%。人工草地随着生长年限的增加,物种丰富度、多样性指数和均匀度指数均有增加的趋势。  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.
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   

17.
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   

18.
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   

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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