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1.
长爪沙鼠是河西走廊北部荒漠草地的优势鼠类,危害严重。古浪县位于河西走廊东部,北部荒漠草地的长爪沙鼠,5月鼠密度在29.1只/hm^2~52.3只/hm^2之间,至9月造成牧草损失586kg/hm^2。通过调查鼠密度和牧草损失量,结果充分显示长爪沙鼠的种群密度与其造成的损失量之间呈明显的正相关关系,其回归方程式为:M=13.96×-8.10。通过防治及综合分析研究后提出在河西走廊的古浪县北部荒漠草地长爪沙鼠的防治指标为5.33只/hm^2,5月份防治。  相似文献   

2.
桑杰东智 《青海草业》2009,18(1):32-33,40
尖扎县草地害虫主要是蝗虫,其次是草原毛虫,集中分布在尖扎滩乡、当顺乡和能科乡的土壤沙质大的干旱草地上。2008年尖扎县蝗虫发生面积达2.067×10^4hm^2,平均虫口密度为53.8头/m^2,其中危害面积1.333×10^4hm^3,占全乡可利用草地面积(5.634×10^4hm^2)的23.7%,危害区损失牧草达500×10^4kg(按375kg/hm^2)。  相似文献   

3.
采用随机抽样方法,对全州5县18个乡的草场进行了害鼠、害虫、毒草的调查。结果表明:危害面积达154.64万hm^2,其中鼠害面积61.96万hm^2、毒草危害面积45.32万hm^2,占可利用草原面积的46.84%,鼠、虫危害年损失牧草96498.37万kg,相当于66.09万只羊单位的全年饲草量。  相似文献   

4.
在陇西县的四个村进行甜高粱栽培试验,平均产草量(剔除水浇地条件产量值)为90.889t/hm^2,比当地高粱(60.54t/hm^2)高43%,地膜种植比露地约高40%,产籽量平均为24654.5kg/hm^2。具有较强的抗旱、抗虫害及抗寒性,适宜在该地区推广种植。  相似文献   

5.
对典型草原布氏田鼠的储草行为和储草种类的选择性研究结果表明:(1)储草期间各洞系鼠群具有比较稳定的采集“领域”,其范围约400~1200m2;(2)平均每个洞系储草16.8±1.53kg(10.25~19.6kg),即每只鼠平均储草792.5±32.7g,储草仅可供其存活58.7天。由于该鼠在越冬期间的自然死亡率在80%以上(试验期间为83.5%)。故而仍有1/3~1/4的储草残留至翌年春季,在地下霉烂后进入土壤。(3)该地区被传的牧草种类仅3~4种。其中冷蒿的重量占总储量94%以上,选择性指数(PI)达5.67。(4)在低温条件下,饲喂冷蒿的鼠,其死亡;率明显低于饲喂禾草组。田鼠的储草对畜牧业生产,尤其是对绵羊抓膘将造成一定危害。  相似文献   

6.
运用能值理论和方法,对锡林郭勒羊草样地生态系统运行的主要驱动力、内在过程、生态资产贮量及其服务功能价值进行了评估。结果表明,1hm^2草地生态系统平均每年对区域经济贡献的宏观经济实际价值约为7285.94元,主要生态资产的宏观经济理论价值约为10580.06元,而1hm^2羊草样地生态系统的替代价值约为39724元。由此可以估算出对羊草草地在开发过程中其环境服务功能及生态资本的损失,另外,也可以根据生物量的减少及GPP的变动情况对生态系统的服务功能及生态资本变动情况进行评估。同时可以根据草地生态系统功能退化的程度进一步估算出区域生态系统损失的情况.可为毕杰粟缔补偿棚制的律寺据供科举依据.  相似文献   

7.
在大田试验条件下采用“盐池”苏丹草(Sorghum sudanense cv.Yanchi)与“邦德”一年生黑麦草(Lolium mzdtiflorum vc.Abundant)轮作研究氮磷钾肥配合施用对饲草产量及养分积累的影响。结果表明:氮磷钾配施处理中(NPKN450kg/hm^2、P2O5 180kg/hm^2、K2O300kg/hm^2)的饲草鲜草产量在各处理中最高,两季合计达162.7t/hm^2;其中苏丹草鲜草产量为102.3t/hm^2,分别比不施肥(CK)、不施氮(PK)、不施磷(NK)和不施钾(NP)处理增产352.7%、356.7%、28.2%和13.9%;黑麦草鲜草产量为60.4t/hm^2,分别比CK、PK、NK和NP处理增产344.1%、255.3%、24.8%和25.3%。配施NPK处理,全生育期饲草干物质目均积累量为65.2kg/hm^2,分别比CK、PK、NK和NP处理高215.0%、197.5%、22.00.4和9.6%,苏丹草与黑麦草的干物质日均积累量分别为104.5kg/hm^2和36.9kg/hm^2。氮磷钾配施显著促进饲草的养分积累,全生育期的饲草N、P2O5和K2O积累量分别为500kg/hm^2、210kg/hm^2和1196kg/hm^2,同时,N、P2O5和K2O日均积累量分别为1.37kg/hm^2、0.58kg/hm^2和3.29kg/hm^2^2;其中苏丹草的日均积累量分别为2.12kg/hm^2、0.79kg/hm^2和4.16kg/hm^2;黑麦草的日均积累量分别为0.84kg/hm^2,0.43kg/hm^2和2.66kg/hm^2。  相似文献   

8.
高山草原放牧系统控制的研究   总被引:5,自引:5,他引:0  
高山草原夏季牧场的牧草营养物质富余达1倍以上,秋季牧草供需相当,冬季可满足80%左右,春季不到40%;草地上的载畜量和畜增重夏牧场是5.08羊单位/hm^2和27.22kg/hm^2,秋牧场是5.59羊单位/hm^2和31.83kg/hm^2,冬季牧场是1.64羊单位/hm^2和-4.38kg/hm^2 ,春季牧场是1.64羊单位/hm^2和-7.10kg/hm^2。在牧草增长率和绵羊种群采食率轨迹图中出现2个平衡点,表明夏,秋牧场的牧草生产有贮藏效应,冬,春牧场为牧草亏缺期。只有采用系统耦合的效应力,方可使放牧系统健康发展。  相似文献   

9.
施磷水平对青引1号燕麦饲草产量和蛋白产量的影响   总被引:1,自引:0,他引:1  
对青引1号燕麦采用不同施磷处理,探讨不同施磷对其饲草产量和蛋白产量的影响,找出最佳的施磷量,为青海省燕麦饲草生产提供了理论依据。结果表明:青引1号燕麦在不同施磷处理下,总分蘖数、株高无显著变化。在施磷量90kg/hm^2时有最大有效分蘖数(2.00个/蘖),在施磷75kg/hm^2时有最大茎粗(0.584cm)。青引1号燕麦在施磷量60kg/hm^2,乳熟期收获时可获得较高的饲草产量(29855.0kg/hm^2)。青引1号燕麦在施磷量75kg/hm^2,开花期收获可获得较高的蛋白产量(2177.2kg/hm^2)。各时期饲草产量和蛋白产量(Y)与施磷量(P)的数量关系均可用Y=a+bp+cP^2表示。  相似文献   

10.
直穗鹅观草引种试验   总被引:1,自引:0,他引:1  
与野生直穗鹅观草相比,经过十多年引种驯化的直穗鹅观草表现出了较强的适应性和较好的生产性能,在林西县生育期约100d,平均干草产量可达4753.3kg,hm^2,生长2年和生长3年的种子产量平均达724.5kg/hm^2,干草产量和种子产量分别比野生直穗鹅观草增加17.0%和23.4%,干草产量与垂穗披碱草(4625.8kg/hm^2)和无芒雀麦(4788.2kg/hm^2)相近,但种子产量明显低于垂穗披碱草(1312.5kg/hm^2)和无芒雀麦(781.7kg/hm^2)。  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.
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   

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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