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1.
不同处理方法对美国截叶胡枝子种子发芽的影响   总被引:2,自引:0,他引:2  
美国截叶胡枝子的硬实率很高,发芽率只有17.3%。经过种子预处理,如采用不同温度下浸种、98%浓硫酸浸泡、机械破皮和机械破皮结合热水浸种等处理,结果表明,机械破皮后用60℃热水浸种处理的效果最好,发芽势和发芽率分别达到64.0%和74.3%;其次是机械破皮,平均发芽率达到50%;浓硫酸浸种可以显著提高种子发芽势,浓硫酸浸种5min效果最好,发芽率达到44.7%;热水浸种的处理效果不佳,最好的90℃热水浸种处理发芽率也仅有26.7%。  相似文献   

2.
美国截叶胡枝子的硬实率很高,发芽率只有17.3%.经过种子预处理,如采用不同温度下浸种、98%浓硫酸浸泡、机械破皮和机械破皮结合热水浸种等处理,结果表明,机械破皮后用60℃热水浸种处理的效果最好,发芽势和发芽率分别达到64.0%和74.3%;其次是机械破皮,平均发芽率达到50%;浓硫酸浸种可以显著提高种子发芽势,浓硫酸浸种5min效果最好,发芽率达到44.7%;热水浸种的处理效果不佳,最好的90℃热水浸种处理发芽率也仅有26.7%.  相似文献   

3.
以白刺花种子为材料,分别采用砂纸摩擦,30%NaOH浸种0.5、1、1.5、2、2.5、3h,90%NaOH浸种5、15、25、35、45、55min,98%浓硫酸浸种10、20、30、40、50min对种子进行硬实处理,在室温(25~28℃)下进行发芽试验。结果表明:砂擦处理效果最好,发芽率为80%;98%浓硫酸处理...  相似文献   

4.
本研究以“腾格里”牛枝子(Lespedeza potaninii Vass.)种子为试验材料,研究了不同的处理方法对去除宿存萼片和破除种子硬实的影响,旨在明确牛枝子种子去除宿存萼片和破除硬实的方法。结果表明:种子破皮机处理4遍和浓硫酸处理12 min时,宿存萼片全部去除;所有处理均能显著提高种子发芽率、发芽势、发芽指数和活力指数,降低硬实率(P<0.05);种子破皮机在处理9遍时,发芽率最高(66.33%),发芽势、发芽指数和活力指数也较高;浓硫酸处理20~30 min,发芽率最高在80.00%以上,发芽势、发芽指数和活力指数也较高。综上所述,由于浓硫酸是一种具有高腐蚀性的强矿物酸,属于危险化学品,生产中操作存在安全风险,而种子破皮机处理4遍可以完全去除宿存萼片,将种子处理9遍可以有效降低硬实率,发芽率可达60.00%以上,且操作方便和安全,易于规模化处理,建议在牛枝子种子生产中推广应用。  相似文献   

5.
不同处理方法对3种豆科灌木种子发芽率的影响   总被引:10,自引:4,他引:6  
采用不同的化学试剂对多花木蓝,紫穗槐和胡枝子3种灌木的种子进行处理,测定其发芽势和发芽率。结果表明,不同处理下发芽率的差异达极显著水平(P<0.01)。其中,多花木蓝的种子,以浓硫酸浸泡15 min和100 g/L硝酸钾溶液浸泡6 h的处理最好,发芽率在72%以上;紫穗槐经浓硫酸浸泡15 min,平均发芽率在76%以上;胡枝子则以30%的双氧水浸泡30 min最好,发芽率为72.7%。因此,选用适宜的方法处理种子,可降低种子硬实率,打破休眠,从而提高种子发芽率。  相似文献   

6.
敖汉苜蓿硬实种子处理方法研究   总被引:10,自引:0,他引:10  
试验以2002年收获的敖汉苜蓿种子为材料,采用不同水温浸种、98%浓硫酸不同浸种时间和石英砂磨破种皮等处理来研究打破敖汉苜蓿种子硬实的效果。结果表明,浓硫酸浸种处理中效果最佳的是浸种60 min,平均发芽率达到99%;不同水温浸种处理中效果最佳的是75℃的热水处理,平均发芽率达到79%。3种处理中以98%浓硫酸浸种60 min的效果最好,其次是石英砂磨破种皮,而各种水温浸种的效果较差。  相似文献   

7.
试验以2002年收获的敖汉苜蓿种子为材料,采用不同水温浸种、98%浓硫酸不同浸种时间和石英砂磨破种皮等处理来研究打破敖汉苜蓿种子硬实的效果.结果表明,浓硫酸浸种处理中效果最佳的是浸种60 min,平均发芽率达到99%;不同水温浸种处理中效果最佳的是75 ℃的热水处理,平均发芽率达到79%.3种处理中以98%浓硫酸浸种60 min的效果最好,其次是石英砂磨破种皮,而各种水温浸种的效果较差.  相似文献   

8.
浸种处理对闽引羽叶决明种子萌发的影响   总被引:5,自引:1,他引:4  
研究了温水、98%硫酸浸种对闽引羽叶决明种子萌发的影响,结果表明,未浸种闽引羽叶决明种子硬实率达87.7%,初始温度100℃温水浸种5~30 min,种子硬实率降至9.7%~13.0%,种子发芽率、发芽势分别上升至87.0%~90.3%和85.0%~88.0%,发芽指数达48.2~56.5,明显优于其他温水浸种处理。98%硫酸浸种10 min,种子硬实率低于2.0%,种子发芽率、发芽势和发芽指数最高,分别为98.3%,97.3%和87.0%。  相似文献   

9.
多花木蓝种子硬实与萌发特性研究   总被引:1,自引:0,他引:1  
通过不同方法时多花木蓝种子进行处理,测定了吸水率、发芽率、发芽指数和活力指数。结果表明,不同处理对提高多花木蓝发芽率的效果差异达极显著水平(P〈0.01)。采用98%浓硫酸浸种时间分别为1、2、3、4、5、6、7、8、9、10min处理中,以6min处理效果最好,发芽率达95%;采用60qC热水浸种时间分别为5、10、15、20、25、30、35min处理中,以25min处理的效果最好,发芽率为71.6%。  相似文献   

10.
浸种处理对圆叶决明种子萌发的影响   总被引:1,自引:0,他引:1  
摘要:为寻求圆叶决明(Chamaecrista rotundifolia)种子硬实破除技术,开展热水和硫酸浸种处理对2个圆叶决明品种种子萌发的影响试验。结果表明,未浸种条件下闽引圆叶决明、闽引2号圆叶决明种子硬实率分别达56.3%、76.0%。初始温度为100 ℃热水浸种3 min,闽引圆叶决明种子硬实率降至11.7%,发芽率升至42.7%,发芽指数达32.1,高于其他热水浸种处理。不同热水浸种处理闽引2号圆叶决明的种子硬实率无显著差异。98%硫酸浸种10 min,闽引圆叶决明、闽引2号圆叶决明的种子硬实率分别降至1.3%、0,而且发芽指数均达峰值,分别为58.9、37.0,相应的发芽率分别为64.7%、80.0%。  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.
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   

15.
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   

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 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   

18.
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   

19.
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   

20.
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.  相似文献   

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