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1.
饲用杂交高粱和苏丹草饲喂草鱼研究   总被引:4,自引:1,他引:3  
牟芝兰 《草业科学》2001,18(6):67-69,74
在高温高湿条件下,饲用杂交高粱和苏丹草长势良好,饲用杂交 高粱在株高1.0-1.5m高时鲜草产量可达37500kg/hm^2,茎叶比为1:0.92,可利用产量为17767.5kg/hm^2。苏丹草鲜草产量为18500kg/hm^2,茎叶比为1:0.40,可利用鲜草产量7400kg/hm^2。草鱼对饲用杂交高粱和苏丹草的采食率分别为36.56%和34.52%,摄食量分别为6.14g/天条和6.45g/天条,试验证明HCN对草鱼无毒副作用,其含量随着生长高度的增加而下降。  相似文献   

2.
优良牧草——科尔沁尖叶胡枝子   总被引:2,自引:0,他引:2  
科尔沁尖叶胡枝子为豆科多年生草本状半灌木,适应于干旱、半干旱区,在内蒙古农牧交错带东段种子9月中旬成熟,产量约636.89kg/hm^2,生育期约115—120d。成熟株高80-90cm,生长2年和3年的鲜干草产量平均为15310.7和5838.5kg/hm^2。科尔沁尖叶胡枝子生育后期基部叶易脱落,收获牧草宜在7月中下旬刈割,留茬高度10cm左右,可调制干草,尤以青贮效果较好,牛羊喜食,羊最喜食。  相似文献   

3.
直穗鹅观草生物学特性及生产性能研究   总被引:1,自引:0,他引:1  
在我国农牧交错区东段引种直穗鹅观草,播种当年生长缓慢,生育期达到拔节期,产草量较低;生长2年可顺利完成生育期开花结实,生长速度和生物量明显增加,生育期为100d,成熟株高达120~125cm。开花期鲜草及千草产量达到24048.8和9048.1kg/hm^2,均高于对照牧草,2年种子产量平均为724.4kg/hm^2。叶量丰富,孕穗期、开花期、乳熟期和成熟期的茎叶比分别为1/1.27、1/0.85、1/0.75、1/0.65,叶量高于对照牧草。再生性较好,不同时期刈割以开花期再生草产量最高。  相似文献   

4.
通过对哈尔滨市几种一年生牧草不同刈割高度下,再生性能及产量的研究,结果表明,刈割时留茬高度不同,对牧草的产量有显著影响。晚熟籽粒苋留茬50 cm,刈割时期为抽穗初期,刈割次数可达到3次,总产量可达到54 500 kg/hm^2;晚熟苦荬菜株高达到60-100 cm,留茬20 cm,产量达到43 950kg/hm^2;菊苣株高50-60 cm,留茬5 cm,产量达到50 700 kg/hm^2;高丹草留茬20 cm,产量达到96 300kg/hm^2。  相似文献   

5.
饲用小黑麦适宜刈割时期及刈割次数研究   总被引:2,自引:0,他引:2  
河北低平原区以中饲828和NTH1048饲用小黑麦为材料,研究了不同刈割时期及刈割次数对其生长发育,饲用品质及产草量的影响,测定分析了不同生育天数内株高、干物质积累量、鲜干比、茎叶比、茎数、粗蛋白含量及二茬草的产草量等性状指标。结果表明:饲用小黑麦的株高、干物质积累量、粗蛋白产量的变化趋势符合Logistic生长模型,鲜干比呈递增趋势,茎数、粗蛋白含量呈下降趋势,符合一元线性回归模型,鲜草产量、茎叶比呈现先升高后降低的趋势,符合二次曲线回归模型。综合分析得出,饲用小黑麦1次刈割应在抽穗初期至抽穗期进行,且1次刈割产草量最高为48 119kg/hm2,优于2次刈割产草量,如春季进行多次刈割时,每次刈割应在拔节期以前完成。  相似文献   

6.
在河南省黄河滩区土壤和气候条件下,燕麦播种量为225 kg/hm2时,通过对比试验,分别测定五寨、林纳、坝莜3号和加燕4个燕麦品种在不同生长期茎叶比、鲜干比、株高、干草产量等指标,研究不同燕麦品种生产性能和农艺性状的动态变化。结果表明:燕麦4个品种在扬花期茎叶比分别为65.34%、58.18%、70.05%、54.72%,鲜干比分别为3.12、3.17、3.07、3.31;燕麦的生长速度呈现出“低—高—低”的“S”形动态模式,在抽穗—扬花期生长速度最大,盛花期株高达分别到108.58、103.43、100.37、113.42 cm,干草产量分别为549.17、514.74、519.63、531.53 g DM/m2。4个燕麦品种均适合在黄河滩种植和生长,表现出生长快、产量高的特点,其中加燕品种各项性能表现更好。  相似文献   

7.
李源  赵海明  谢楠  刘贵波  谢俊雪 《草地学报》2012,20(6):1093-1098
为揭示不同种植密度和留茬高度下高丹草(Sorghum bicolor×S. Sudanense)生产性能间的差异性,以国审冀草1、2号高丹草为试验材料,采用随机区组试验设计,于2008-2010年在海河低平原农区连续3年小区试验的基础上,比较分析了不同种植密度、留茬高度对冀草1、2号高丹草株高、茎叶比、群体密度、鲜干比以及草产量的影响。结果表明:不同种植密度(7.5~37.5万株·hm-2)处理下,冀草1、2号高丹草的株高、茎叶比及总草产量无显著差异,而鲜干比和群体密度在相同茬次不同处理间表现出一定的显著性差异(P<0.05)。不同刈割时期(抽穗期刈割、株高1.5 m左右刈割)的留茬高度(5,10,15,20和25 cm)处理表明,抽穗期刈割时不同留茬高度下冀草1、2号高丹草各性状值间无显著性变化;而株高在1.5 m左右刈割时留茬高度为20 cm处理下冀草1、2号高丹草总鲜、干草产量显著高于留茬高度为5 cm的处理(P<0.05)。综合分析得出,海河低平原农区,抽穗期刈割时,冀草1、2号高丹草的种植密度在7.5~37.5万株·hm-2均可,且不同留茬高度对2茬草的生产性能无显著性影响,而株高1.5 m左右刈割时,最佳留茬度应为20 cm。  相似文献   

8.
鸭茅系世界著名多年生冷季型优质牧草,在我国草地畜牧业发展和生态建设中起着重要作用。为系统地探明我国鸭茅品种(系)在表型水平上的多态性及变异规律,本研究对我国鸭茅8个品种和1个新品系单株的物候期、抗锈病能力、越夏率、生长速度、鲜干草产量、鲜干草茎叶比、鲜干比、分蘖数、植物学表型性状及DUS性状进行了系统研究,结果表明,1)各鸭茅品种(系)生育期、抗锈病能力、越夏率、生长速度、生产性能差异明显,以‘02-116’新品系表现较为突出;2)供试12个表型性状在品种(系)间差异均达到极显著(P<0.01)水平,变异系数变幅为21.64%(倒二叶长度)~106.20%(穗叶距),穗叶距、株高、茎上部节间长度、倒二叶宽度、株幅等性状与鸭茅产量显著相关;3)主成分分析表明前4个主成分因子累计贡献率达68.225%,鸭茅植株株型的形成和生长速度的动态变化,在很大程度上由叶片长度、叶片宽度、株高、穗叶距等共同决定;4)各品种(系)在7个供试DUS性状上均表现出不同程度的群体差异;5)品系‘02-116’与品种‘川东’、‘古蔺’等在主要形态上存在一定差异。  相似文献   

9.
高丹草生长动态及收割期的研究   总被引:3,自引:1,他引:2  
对高丹草不同生长阶段的株高、生长速度、物质积累动态及产量组成进行了研究,并对其营养价值进行评定.结果表明,旱作条件下,高丹草株高、生长速度、产草量及茎/叶变化动态符合Logistic模型,苗期生长缓慢,拔节期生长最快,拔节期过后生长速度减缓,表明拔节期是营养体产量形成的关键时期.干/鲜及营养物质变化符合一元线性回归模型...  相似文献   

10.
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   

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.
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   

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.
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   

19.
<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   

20.
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   

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