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1.
张春梅 《草业与畜牧》2010,(6):16-16,41
对贮存2年的结缕草种子通过不同浓度NaOH、H2SO4以及H2O2的处理结果表明:NaOH在20%~40%浓度范围内,结缕草种子发芽率由13%提高到80%;H2SO4在49%浓度下,结缕草种子发芽率由13%提高到73%.  相似文献   

2.
蛭石引发对结缕草种子发芽率和发芽速度的影响   总被引:5,自引:0,他引:5  
试验采用最终发芽率分别为90%(当年收获)、83%(贮藏1年)、74%(贮藏2年)、15%(贮藏3年)的结缕草(Zoysia japonica)种子为材料,以蛭石作为固体引发基质,研究水势和时间对种子最终发芽率、50%发芽时间和平均发芽时间的影响.结果表明,蛭石引发处理对当年收获和贮藏1年的结缕草种子的最终发芽率没有影响,但显著提高了贮藏2年和3年种子的最终发芽率,分别比对照提高了9%和12%;随着引发处理水势的增加和处理时间的延长,4份不同贮藏年限的种子50%发芽时间和平均发芽时间均有不同程度的缩短,分别比对照缩短1.8~3.0 d和2.1~8.2 d.与PEG溶液引发相比,蛭石固体引发最佳处理的水势更高,为-0.4~-0.1MPa;处理时间更长,为3~4 d.  相似文献   

3.
虎尾草种子萌发特性的研究   总被引:4,自引:1,他引:3  
余玲 《草业科学》1999,16(3):51-54
研究了温度和预处理对虎尾草种子萌发的影响及贮藏时间与种子后熟的关系。结果表明,虎尾草种子最适萌发温度是20/30℃或20/30℃变温;破除休眠的最佳方法是预选 冷冻;初次和末次计数时间第2d和第5d;随着贮藏时间的增加,种子发芽率显著增加,休眠率显著下降;室内自然条件下经过13-18个月贮藏后,种子可通过后熟期。  相似文献   

4.
贮藏期对结缕草种子生理生化的影响   总被引:8,自引:2,他引:6  
测定结缕草种子不同贮藏年限的活力水平。结果表明,在自然条件下贮藏,结缕草种子的活力下降较快,发芽率,发芽势、发芽指数、活力指数、TTC含量、ATP含量以及不正常种苗等指标与贮藏期限呈显著相关。TTC法和ATP法所测活力指标与贮藏期限呈极显著和显著相关。种子浸出液电导率和葡萄糖含量与贮藏期的相关性较低。在萌发初期酸性磷酸酶的活性随着贮藏的延长,在降低后又有所增长,但均低于1998年收获而未经贮藏的种  相似文献   

5.
NaOH处理结缕草种子对种带真菌的影响   总被引:1,自引:0,他引:1  
用20% NaOH处理2002、2003和2004年收获的结缕草(Zoysia japonica)种子,采用PDA培养法测定种子带菌率、种带真菌的种类和分离频率.结果表明:NaOH处理结缕草种子降低其带菌率,与表面消毒效果相当,处理后随着贮藏时间的延长,种子带菌率升高.经过NaOH处理的种子再进行表面消毒效果不明显.在供试材料中共检出25属34种真菌,其中曲霉、青霉的分离频率最高.用NaOH浸泡和表面消毒种子均可以降低其带菌种类,且二者效果大致相同.  相似文献   

6.
PEG渗调处理改善结缕草种子活力的研究   总被引:1,自引:0,他引:1  
以不同活力的结缕草种子为材料,研究了PEG不同浓度、不同处理时间和不同浸种温度对种子活力的影响。结果表明,PEG渗透处理自然贮藏2~5年活力降低的结缕草种子效果显著,发芽速度明显提高,种苗质量得到改善。在PEG处理浓度25%、处理时间24h时,25℃下渗调结果比15℃下效果好。经PEG渗透调节之后,结缕草种子萌发进程中的代谢过程有所改变,酸性磷酸酶与过氧化物酶的活性、ATP的含量均比对照有明显的提高。  相似文献   

7.
PEG渗调处理改善结缕草种子活力的研究   总被引:20,自引:2,他引:18  
以不同活力的结缕草种子为材料,研究了PEG不同浓度、不同处理时间和不同浸种温度对种子活力的影响。结果表明,PEG渗透处理自然贮藏2~5年活力降低的结缕草种子效果显著,发芽速度明显提高,种苗质量得到改善。在PEG处理浓度25%、处理时间24h时,25℃下渗调结果比15℃下效果好。经PEG渗透调节之后,结缕草种子萌发进程中的代谢过程有所改变,酸性磷酸酶与过氧化物酶的活性、ATP的含量均比对照有明显的提  相似文献   

8.
结缕草种子(颖果)解除休眠前后的颖显微结构   总被引:4,自引:0,他引:4  
董厚德  宫莉君 《草地学报》2001,9(4):243-247
对解除休眠前的结缕草种子通过扫描电镜观察,发现颖结构致密,其上覆盖一层脂类物质。在平行的颖脊上有整剂排列的颖孔,这些颖孔均被Si质的颖孔盖所覆盖。经过处理,解除休眠后,脂类物质及颖孔盖脱落,颖孔被打开,构成颖的纤维网络清晰可见,种子内外的水、气、交换可顺利进行,减少胚生长的阻力,发芽率达到潜在生活力水平,经过牛胃消化排出的结缕草种子,颖结构的形态变化及发芽率与人工处理的结果基本相同。  相似文献   

9.
[目的]探究贮藏年限对不同居群白羊草(Bothriochloa ischaemum)种子活力的影响。[方法]采用收获于2017年、2018年、2019年及2020年的5个居群(代县、平鲁、平定、柳林和太谷)白羊草种子进行发芽试验,分析其发芽率、发芽指数、平均发芽时间及幼苗活力指数随贮藏年限的变化规律,探讨不同居群白羊草种子的耐贮藏性差异。[结果]贮藏年限、居群及两者的交互作用对白羊草种子发芽率、发芽指数及幼苗活力指数存在极显著(P<0.01)影响。不同居群白羊草种子发芽率、发芽指数及幼苗活力指数随贮藏年限的增加均呈下降趋势。太谷居群白羊草种子收获当年以及贮藏1和2年的发芽率、发芽指数差异不显著(P>0.05),贮藏3年时显著(P<0.05)下降,幼苗活力指数随贮藏年限的增加无显著(P>0.05)变化;其他居群白羊草种子收获当年的发芽率、发芽指数及幼苗活力指数均显著(P<0.05)高于贮藏1、2、3年。柳林居群白羊草种子在收获当年的发芽指数、幼苗活力指数均高于其他居群,平均发芽时间低于其他居群,发芽率较高。贮藏年限对白羊草种子的平均发芽时间存在极显著(P<0.01)影响,平均发芽时间随贮藏年限的增加而延长,且居群对白羊草种子平均发芽时间也存在极显著(P<0.01)影响,但贮藏年限与居群的交互作用对白羊草种子平均发芽时间的影响不显著(P>0.05)。[结论]不同居群白羊草种子活力均在收获当年保持较高水平,其中,柳林居群白羊草种子活力水平最高。太谷居群白羊草种子活力在贮藏3年内保持较高水平,耐贮藏性最好;而其他居群均不适合长期贮藏。  相似文献   

10.
种子的分离及鉴定是土壤种子库研究的基础,漂浮浓缩法很适合单种物种种子的分离.本文研究了不同浓度NaCl盐溶液及漂浮时间对结缕草种子漂浮率的影响.结缕草种子的漂浮率随着漂浮溶液浓度的增大而提高,随着漂浮时间的增加而降低.当NaCl盐溶液的浓度达到或者超过21.26%时,在10 min内结缕草种子漂浮率一直为100%,不随着漂浮时间的变化而变化,表明漂浮浓缩法可以用于土壤种子库研究中结缕草种子的分离.  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.
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   

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   

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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   

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