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1.
红三叶N、P、K、Ca、Mg元素含量与动态研究   总被引：5，自引：0，他引：5  
本文研究了红三叶（Trifoliumpratense）各器官在不同生育期N、P、K、Ca、Mg等元素的含量，目的在于揭示其各器官对N、P、K、Ca、Mg的积累能力、对不同元素的选择性吸收以及N、P、K、Ca、Mg在各器官的季节动态。结果表明：红三叶不同器官对各元素的积累能力不同，N：叶＞花＞根＞茎；P：花＞叶＞根＞茎；K和Ca：叶＞花＞茎＞根；Mg：根＞叶＞茎＞花。不同器官对元素选择性吸收系列不同，根为N＞K＞Ca＞Mg＞P；茎：N＞Ca＞K＞Mg＞P；叶：N＞Ca＞K＞P＞Mg；花：N＞Ca＞K＞P＞Mg；红三叶是一种典型的N－Ca型植物。此外，K、P、K、Ca、Mg在根、茎、叶、花中的动态变化有6种基本类型，Ⅰ－渐增型（／）、Ⅱ－递减型（＼）、Ⅲ－U型、Ⅳ－∩型、Ⅴ－增波型（～）、Ⅳ－降波型（～）。  相似文献   

2.
通过对广西田东地区“桂热芒82”号叶片中N、P、K、Ca、Mg、S6种营养元素含量进行全年跟踪分析，结果表明：“桂热芒82号”生长周期分为4个阶段：营养生长期(8—12月)、生殖生长期(12—2月)、果实膨大期(2-5月)、果实成熟期(5-7月)。叶片养分年平均含量大小为：第一蓬Ca＞N＞K＞Mg＞S＞P、第二蓬Ca＞N＞K＞S＞Mg＞P。各阶段叶片养分含量变化规律有所差异，第一、二蓬叶片变化基本规律一致。第一、二蓬叶片Ca、N、K、Mg、S、P含量（g/kg）为：19.84、15.36、8.34、1.90、1.58、1.32和23.45、14.46、7.22、1.56、1.77、1.18，该品种对钙肥的需求量较大。  相似文献   

3.
对海南主栽芒果品种台农和金煌芒的叶片养分的变化动态进行了分析。结果表明，相同栽培模式下，芒果叶片养分含量在不同品种、不同生长发育阶段和不同物候期之间存在显著的差异，但总体规律为：Ca＞N＞K＞Mg＞P＞Mn＞Fe＞Cu＞Zn。营养生长期间，不同月份芒果叶片中N、P、K、Mg含量基本保持在同一水平上；生殖生长期间，养分从叶片转移至花芽中，叶片养分明显下降。对于大量元素N、P、K、Mg而言，8月份至12月份叶片养分波动较小，因此10月份芒果的叶片可以作为叶片营养诊断的采样时间。  相似文献   

4.
为了探明紫穗槐植株的营养结构特征,测定了生长季(6,7,8,9月)紫穗槐叶和不同径级根、茎的10种养分(有机碳、N、P、K、Ca、Mg、Fe、Mn、Cu、Zn)含量。结果表明,1)根和茎的N、P、K含量与径级呈典型逆相关关系,即随着径级的增大养分含量减少,含量最高的部位集中于叶及小径级的根、茎。2) 各级根、茎的Ca、Mg、Fe、Mn、Cu、Zn含量没有固定的分布特征。3)微量元素间的相关性比其与大量元素的相关性差,茎中所含相关元素对最多,其次是叶,根最少;从元素方面看,N、P、K与较多的元素间存在相关性,与C、Zn、Ca相关的元素较少。4)生长季紫穗槐叶的C、N、Ca、Mn、Cu含量高于根和茎,叶中大量元素的含量顺序为C＞N＞K＞Ca＞Mg＞P,微量元素为Fe＞Mn＞Zn＞Cu。  相似文献   

5.
通过对云南保山地区“帕拉英达”芒果成熟功能叶片中N、P、K、Ca、Mg、S等 6种营养元素含量进行跟踪分析,结果表明：叶片养分年平均含量大小为： Ca＞N＞K＞P＞Mg＞S,其全年平均含量（g/kg）分别为：25.16、15.20、4.56、1.39、1.35、1.34;不同生育期叶片养分含量变化规律有所差异,根据叶片养分含量的变化规律,可把“帕拉英达”芒果生长周期分为4个阶段：营养生长期(8－次年1月)、生殖生长期(1－3月)、果实膨大期(4－5月)、果实成熟期(6－7月)。  相似文献   

6.
玛曲高寒草地土壤养分对不同利用方式的响应   总被引：6，自引：0，他引：6  
选取玛曲高寒围封草地(封育草地、修复草地)、开垦地(燕麦地)以及不同退化程度草地(中度退化草地、黑土滩草地、沙化草地),对土壤养分进行分析研究.结果表明:草地的开垦与退化,使土壤有机碳(SOC)、全N、有效N、全P、有效P含量显著下降,而pH值却显著升高.随着草地的开垦与退化,全K、有效K变化不明显,沙化草地土壤中全Ca含量显著增高,约是其它利用方式的3倍以上.中度退化草地的全Mg含量最高,燕麦地、封育草地也出现了较高的Mg含量,但无显著差异.各项养分指标之间存在一定相关性, 尤其是SOC与全N、有效N呈极显著正相关,与全P、有效P、全K、有效K、全Mg含量呈显著正相关,与全Ca含量呈显著负相关关系.土壤pH值与土壤全Ca含量呈显著正相关关系,而与土壤其他养分呈显著负相关关系.土壤全Ca与全Mg之间呈显著正相关.  相似文献   

7.
在田间试验的条件下研究了苏丹草Sorghum sudanense干物质积累及养分吸收规律.结果表明,苏丹草干物质积累量随着生长进程不断增加,出苗后39～62 d,干物质量增加最快,占干物质总量的35.4%,日积累量也最大,为335.59 kg/(hm2·d).试验条件下,苏丹草鲜草产量为190.00 t/hm2,需吸收N 489.9、P2O5 122.4、K2O 585.3、Ca 106.6、Mg 38.3 kg,N:P2O5:K2O:Ca:Mg为1:0.25:1.19:0.22:0.08;需吸收Fe 6 364.6、Mn 1 383.9、Cu 236.2、Zn 1 498.0 g,N:Fe:Mn:Cu:Zn为1 000:13.0:2.8:0.5:3.1.养分吸收量和比例可作为苏丹草合理施肥依据.  相似文献   

8.
铁尾矿区沙棘-桑树人工混交林的养分分配状况   总被引：2，自引：1，他引：1  
为了评估铁尾矿区废弃地的植被恢复中,利用沙棘-桑树人工混交林提高林地养分总体水平的可行性,测定混交林中沙棘、桑树和草本植物的地上部分、根系及枯枝落叶中的N、P、K、Ca、Mg含量与贮量,测定沙棘、桑树根系周围土壤中的养分含量。结果表明:沙棘的根、干、枝、叶、皮中的N含量明显高于桑树,尤其是不同土层根系中的N含量可达到桑树根系的3.03～4.33倍,沙棘根系中的Ca、Mg含量高于桑树,P含量与桑树相近,而桑树地上部分的P、K、Ca、Mg含量以及各土层根系中的K含量大多高于沙棘;沙棘根系周围土壤中的全N含量高于桑树根系周围土壤,其平均含量为桑树的1.88倍,根系周围表层0～20 cm土壤的全N含量为桑树的3.18倍;混交林中乔木、草本、枯落物的总养分贮量大小为:沙棘>枯枝落叶>桑树>草本植物,其中沙棘的养分贮量占混交林系统养分总贮量的56.10%。研究结果提示:沙棘在整个混交林系统的养分分配中起到支配性作用,可为桑树的正常生长发育提供良好的养分空间,沙棘-桑树混交林是生态效益与经济效益双赢的混交模式。  相似文献   

9.
采用尼龙网袋分解法,将一定量的黑麦草根系和地上留茬(统称黑麦草残留物)置于田间耕作层令其自然分解,分别于埋设后11,39,70,109,161和244 d收集尼龙网袋内的样品,洗净,烘干,称重后用于分析全量N、P、K、Ca、Mg、Mn和Fe的含量.结果表明,黑麦草残留物在大田中通过生物降解,将养分释放到土壤中,在后作水稻的生长发育过程中,分解初期的释放量较高,埋设10 d后黑麦草残留物样品中近90%的Ca和37%～50%的C、N、P、K和Fe被释放,Mn和Mg则只有0.4%～13.4%被释放.在早稻生长过程中黑麦草残留物有74.9%被分解,C、N、Mn和Mg的矿化率均在80%以下,表现出一定的缓释效应.晚稻收获时各养分的释放率达到92%～99%.理论上黑麦草根系可以为0～20 cm土层贡献有机质、N、P、K、Fe、Mn、Mg和Ca分别达到865.42 g/kg,26.92 g/kg,1.75 g/kg,23.83 g/kg,2 741 mg/kg,75 mg/kg,162 mg/kg和46 mg/kg.  相似文献   

10.
以30年生枳砧清家脐橙和纽荷尔脐橙为材料，分析果实生长发育过程中N、P、K、Ca、Mg、和S 6种大量营养元素含量和累积量变化。结果表明，果实生长发育过程中，纽荷尔和清家果实中N、P、Mg和S含量4月最高，Ca在10月最高，纽荷尔和清家K含量分别在9月和7月最高；纽荷尔果实的N、P、K、Mg和S主要累积时期为7～9月，Ca主要累积时期为9～10月；清家果实的N、P、K、Mg和S主要累积时期为6～8月，Ca主要累积时期为8～10月。清家脐橙果实中大量营养元素的主要累积时期比纽荷尔脐橙早1个月左右。  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.
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   

14.
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   

15.
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   

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.
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   

18.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

19.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

20.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
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