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1.
试验采用随机设计在内蒙古短花针茅荒漠草原通过测定生产力和越冬率,对引进和收集的13份禾本科牧草、9份豆科牧草进行了适应性评价,旨在筛选出适合当地种植的优良牧草品种。结果表明:沙生冰草和蒙古冰草在引种的禾本科牧草中生产力较高,分别为2 198.4kg/hm2和2 009.3kg/hm2,越冬率分别为87%和85%;豆科牧草中,黄花苜蓿和草原3号苜蓿的生产力分别为900.2kg/hm2和871.3kg/hm2,越冬率分别是85%和88%。因此,以上4个牧草品种适宜在短花针茅荒漠草原用于改良天然草地和建设人工草地。  相似文献   

2.
试验对16种从国外引进的禾本科牧草在荒漠草原的适应性及营养价值评定进行了研究,结果表明:美国赖草、美国灰赖草、沙生冰草及西伯利亚冰草越冬率较高,均在90%以上;披碱草和赖草属牧草生长速度较快,尤其是灰赖草;美国赖草、灰赖草鲜重均达到6000kg/hm2以上,加拿大新麦草、保加利亚新麦草鲜草产量均在4000kg/hm2以上;护坡型冰草、西伯利亚冰草、沙生冰草营养价值较高、适应性强、抗逆性好,是优质牧草,可以作为荒漠草原地区推广种植的首选牧草;美国赖草、灰赖草虽然产量高,抗逆性强,能够适应荒漠草原地区低温和干旱等极端条件,但适口性较差,可作为生态用种加以利用。  相似文献   

3.
在临潭县冶力关镇海拔2 590 m的梯田,于早春以不同播量种植甘肃红豆草(Onobrychis viciaefolia cv.Gansu)(70、100和130 kg/hm2)和甘农一号杂花苜蓿(Medicago varia cv.Gannong No.1)(7、10和13 kg/hm2 ),观测其物候期、株高、生长率、产量、营养动态及翌年越冬率,探讨其在高寒山区的生产性能及适应性。结果表明,播种当年两种牧草均未完成生活史,停留在分枝期,但翌年越冬率都在95%以上,都能安全越冬;甘肃红豆草100 kg/hm2播量下的鲜草和干草产量最高,分别为11 734.0和3 357.8 kg/hm2 ,甘农一号杂花苜蓿13 kg/hm2播量下的鲜草和干草产量最高,分别为5 217.5和1 690.9 kg/hm2 。不同播量对两种牧草的养分影响较小,其变化趋势一致,在8月5日之后粗蛋白、粗灰分和磷含量呈降低趋势,粗纤维含量逐渐上升。甘肃红豆草和甘农一号杂花苜蓿分别以100 kg/hm2播量和播量13 kg/hm2的草产量高,且适应性强,饲料利用价值较高,在甘肃临潭县可作为饲草利用。  相似文献   

4.
灌溉对紫花苜蓿种子产量和质量的影响   总被引:6,自引:0,他引:6  
紫花苜蓿是一种全球性栽培、适应性广泛、品质优良的饲料作物。其草产品市场前景广阔 ,种子需求量大 ,特别是优质苜蓿品种 ,更是供不应求。我国苜蓿种植历史悠久 ,已有 2 0 0 0多年的历史 ,但种子产量不高 ,质量欠佳 ,一般仅为 5 0~15 0kg/hm2 ,而欧美等国家高达 997~ 1395kg/hm2 。为提高苜蓿种子产量 ,改善品质 ,满足种植业结构调整 ,退耕还草及生态环境治理 ,苜蓿种植面积迅速扩大对种子的迫切需求 ,我们齐齐哈尔市草原监理站为我省西部半干旱缺水地区建立苜蓿种子生产基地 ,探索可借鉴易行的栽培方法。为此我们研究了不同灌溉时间对苜…  相似文献   

5.
肃北县草原资源调查   总被引:1,自引:0,他引:1  
通过应用3S技术一体化与固定样地、路线调查相结合,对肃北县天然草原资源进行调查,确定了肃北县草地类型、面积、分布及物种组成,并对草地盖度、高度和产草量进行了监测研究。结果表明,1)肃北县有天然草原5 181 889 hm2,划分为9个类,17个亚类,19个组,29个型;2)肃北县各类草原鲜草产量从高到低依次为:低平地草甸5 093 kg/hm2,温性草原化荒漠3 094 kg/hm2,高寒草甸2 561 kg/hm2,高寒灌丛草甸1 933 kg/hm2,高寒荒漠1 822 kg/hm2,温性荒漠化草原1 665 kg/hm2,温性荒漠1 183 kg/hm2,高寒草原1 143 kg/hm2,温性草原760 kg/hm2;3)肃北县天然草原年总产鲜草886 091.71万kg,折合干草(风干)304 763.85万kg;肃北天然草原理论载畜量为135.42万羊单位,目前全县各类牲畜折40.75万羊单位;4)肃北县具有丰富而珍贵的植物资源,南部祁连山区分布的植物有210种,分属42科129属,其中中低等以下的牧草有185种,占植物群落的88%;中等以上的有25种,占12%;马鬃山区分布的植物种有86种,分属23科54属,其中优良牧草有70种,占植物群落的81%。  相似文献   

6.
高寒牧区牧草品种短缺,引进优良牧草对于高寒地区畜牧业的发展和生态环境的保护具有重要意义。本试验引进饲用黑麦草品种在高寒地区种植,结果得出该品种在高寒地区生长的平均株高为170 cm左右,鲜草产量达60 000 kg/hm2以上。表明该品种抗旱性、抗寒性较高,适应性强,很有推广种植价值。  相似文献   

7.
苜蓿具有适应性强、产量高、品质好、营养丰富、抗旱、耐盐碱以及固氮保持水土等诸多优点.因此,苜蓿是种植牧草的首选优良草种.随着草原禁牧及牧草的产业化发展,人工草地的面积在不断增加,苜蓿的种植面积也呈逐年增长趋势.但苜蓿越冬问题一直是制约苜蓿生产的关键问题.  相似文献   

8.
河西干旱荒漠区禾本科牧草引种栽培试验   总被引:2,自引:0,他引:2  
对来自加拿大的5个禾本科牧草品种在河西走廊荒漠绿洲边缘区进行了3年引种栽培试验,结果表明:Largo、Dahurian和Haymaker 3个晶种具有干草产最高和生态适应性强的特点,在种植第2年干草产量分别为13.1t/hm2、12.8t/hm2和12.3t/hm2,但Largo干草质量相对较差.Signal和Adanac具有较强的抗旱、抗寒性和抗病虫能力,且Adanac具有较强的耐盐碱能力,但产草量低于Largo、Haymaker和Dahurian.品种Haymaker和Dahurian的种子产晕较高,种植第2年种子产量分别为998kg/hm2和1020kg/hm2,而Largo的种子产晕相对较低.总体评价认为,Haymaker、Dahurian、Signal和Adanac:在河西干旱荒漠区及同类地区具有广泛的推广和应用价值.  相似文献   

9.
苜蓿被誉为"牧草之王",是全世界种植面积最大的优质牧草品种之一,因其适应性强、产量高、品质好而在畜牧业发展中起着重要的基础作用。但苜蓿的种植在齐齐哈尔地区发展速度相对迟缓,受着气候、种植等因素的制约。1概况1.1自然条件齐齐哈尔市位于黑龙江省西部松嫩平原,辖九(市)县、七区,草原面积55.07万hm2。属中温带大陆性气候,冬季严寒  相似文献   

10.
四份披碱草属牧草在同德地区生产性能评价   总被引:1,自引:0,他引:1  
以四份披碱草属牧草材料为研究对象,在青藏高原高寒地区旱作条件下从生育期、产量、茎叶比等方面进行了生产性能评价,为其在生态环境建设和种子生产方面提供理论依据.结果表明,四份材料在同德地区均能安全越冬,表现出较强的抗寒、抗旱能力.各材料在生长第二年产量最大,青牧1号老芒麦和同德老芒麦在同德地区产量表现较高,其在第二年鲜草、干草和种子产量分别为36500.2 kg/hm2、44894.6 kg/hm2、908.7 kg/hm2和35500.2 kg/hm2、10924.0 kg/hm2、902.4 kg/hm2.且这两个品种叶量丰富,是饲喂家畜的优质牧草.四份披碱草属材料适宜在海拔3200m左右的地区种植.  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.
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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