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1.
4种补血草属植物种子发芽对温度的响应   总被引：3，自引：0，他引：3  
王俊年  李得禄 《草业科学》2012,29(2):249-254
以乡土种黄花补血草（Limonium aureum）和引种于民勤沙生植物园的二色补血草（L.bicolor）、大叶补血草（L.gmelinii）、耳叶补血草（L.otolepis）4种植物种子为材料,进行了温度对种子发芽影响的研究。结果表明,种子发芽率达最大值的温度范围黄花补血草为10～20 ℃,发芽率为95％～97%;二色补血草为15～25 ℃,发芽率为95％～100%;大叶补血草为20～35 ℃,发芽率在98%以上;耳叶补血草为20～30 ℃,发芽率为97.33％～98.67%。种子发芽势达最大值的温度范围黄花补血草为15～20 ℃;二色补血草15～20 ℃;大叶补血草为20～35 ℃;耳叶补血草为25～30 ℃。发芽指数达最大值的温度范围黄花补血草为15～20 ℃;二色补血草20～25 ℃;大叶补血草为25～30 ℃;耳叶补血草为20 ℃。发芽指数出现最大值的温度不一致,黄花补血草、二色补血草、耳叶补血草均在20 ℃出现最大值,发芽指数分别为36.26、37.26和24.34,大叶补血草在30 ℃出现最大值,发芽指数为33.12。幼苗长度最大值的温度范围黄花补血草为15～20 ℃;二色补血草为20～25 ℃;大叶补血草为25～30 ℃;耳叶补血草为20～25 ℃,4种补血草幼苗长度最大值分别出现在20、15、25和25 ℃,分别为4.31、2.38、1.59和1.38 cm。综合各项指标,分析认为黄花补血草、二色补血草、大叶补血草和耳叶补血草种子发芽的适宜温度范围分别为15～20、20～25、25～30和20～25 ℃。  相似文献   

2.
以8种不同类型的柑橘砧木实生苗为试验材料,在处理条件较为一致的无土栽培系统中进行不同pH值(3.5和9.0,以6.0为对照)处理,测定胁迫下植株的形态表现、生长量指标以及与逆境相关的生理生化指标,利用主成分分析法和隶属函数法对柑橘砧木的耐酸/碱性进行综合性评价。结果显示,与对照相比,酸碱胁迫下供试砧木的各项指标均发生了变化,且变化幅度因砧木不同而不同。利用隶属函数法计算供试材料的耐性综合能力值,其值越大耐性越强,反之越弱。枳(Z-022)是耐酸性较强的砧木,资阳香橙是耐碱性较强的砧木,而KPJ-015和卡里佐枳橙分别是对酸胁迫和碱胁迫较为敏感的柑橘砧木。  相似文献   

3.
An electronic particle counter with attached particle-size analyzer was configured to directly determine concentration, mean cell volume, and volume distribution of erythrocytes in llama blood. Blood from 38 healthy llamas was used to characterize erythrocytic measurements and serum iron values for this species. Volume distribution curves for llama erythrocytes were similar in shape to those of other species. These curves had a unimodal, symmetric shape with a tail skewed to the right. Reference ranges for directly measured mean cell volume, erythrocyte concentration, hemoglobin concentration, and mean cell hemoglobin concentration were 21 to 28 fl, 11.3 x to 17.5 x 10(6) cells/microliters, 12.8 to 17.6 g/dl, and 43.2 to 46.6 g/dl, respectively. Reference ranges for serum iron concentration, total iron-binding capacity, and transferrin saturation were determined to be 70 to 148 micrograms/dl, 230 to 370 micrograms/dl, and 22 to 50%, respectively.  相似文献   

4.
The resistance to anti-microbial agents of bacteria isolated from pathological conditions of birds in Victoria, 1978 to 1983, was determined for isolates of Escherichia coli, Salmonella species, Staphylococcus aureus, Pasteurella multocida, P. anatipestifer, Yersinia pseudotuberculosis and Haemophilus paragallinarum. The isolates of E. coli had a high prevalence of resistance to tetracycline and sulphonamides, and a lower prevalence of resistance to furazolidone and sulphamethoxazole-trimethoprim. The isolates of Salmonella spp commonly had resistance to tetracycline, sulphonamides, furazolidone and sulphamethoxazole-trimethoprim. Almost half the isolates of S. aureus showed resistance to lincomysin and many showed resistance to penicillin. Resistance to tetracycline was found in isolates of P. multocida, P. anatepestifer and Y. pseudotuberculosis. Some isolates of H. paragallinarum showed resistance to sulphonamides, streptomycin and sulphamethoxazole-trimethoprim.  相似文献   

5.
A total of 50 Staphylococcus intermedius strains isolated in France from canine pyodermas in 2002 were investigated for their susceptibility to various antimicrobial drugs. Antimicrobial susceptibility was assessed using a 2-fold serial dilution method in Mueller-Hinton agar, and the minimal inhibitory concentrations (MICs) were determined. About 62% of the 50 strains tested were producers of beta-lactamase and categorized as penicillin-resistant. About 26% demonstrated resistance to sulphonamides, 46% to oxytetracycline, 30% to chloramphenicol, 28% to streptomycin, kanamycin, neomycin or erythromycin, 22% to clindamycin, 6% to doxycycline, 2% to gentamicin, enrofloxacin, marbofloxacin or pradofloxacin. Acquired resistance was not observed to a clavulanic acid-amoxicillin combination, oxacillin, cephalosporins (cephalexin, ceftiofur and cefquinome), trimethoprim, a sulphamethoxazole-trimethoprim combination and florfenicol. About 42% were simultaneously resistant to three or more antimicrobial classes (multiresistance). All isolates with acquired resistance to erythromycin were also resistant to streptomycin and neomycin/kanamycin. About 22% of isolates exhibited cross-resistance between erythromycin and clindamycin and all clindamycin-resistant isolates also exhibited resistance to erythromycin. Resistance to penicillin, oxytetracycline and chloramphenicol was also positively associated with resistance to erythromycin and streptomycin.  相似文献   

6.
Resistance to selected antibiotics was studied in 325 strains of Staphylococcus aureus, isolated from foodstuffs. Out of these strains, 50.46% were resistant to penicillin, 15.7% to ampicillin, 4% to streptomycin, 5.2% to erythromycin, 5.8% to chloramphenicol, 18.5% to tetracycline, 18.2% to oxytetracycline, 2.5% to gentamycin, 1.6% to canamycin, 53.5% to colistine and 9.2% to bacitracin. Eighty-five strains (26.15%) were sensitive to all the antibiotics used; 107 strains (32.92%) were resistant to one antibiotic, and 133 strains (40.93%) to two or more antibiotics.  相似文献   

7.
目的检测三株柔嫩艾美耳球虫对六种药物的耐药性,为防治球虫病制定临床用药方案提供依据。方法鸡体实验法检测巢湖、六安、肥东三株柔嫩艾美耳球虫对马杜拉霉素、盐霉素、莫能菌素、磺胺喹嗯啉钠、地克珠利、妥曲珠利的耐药性,以抗球虫指数（ACI）、病变记分减少率（RLS）、相对盲肠卵囊产量（ROP）和最适抗球虫活性百分率（POAA）四项指标综合判定。结果巢湖株对地克珠利,盐霉素与莫能菌素轻度耐药,对马杜拉霉素中度耐药,对托曲株利和磺胺喹嗯啉钠重度耐药,六安株对地克株利与托曲株利重度耐药,对磺胺喹嗯啉钠中度耐药,对盐霉素轻度耐药,对马杜霉素敏感,肥东株对磺胺喹嗯啉钠完全耐药,对莫能菌素重度耐药,对马杜霉素与盐霉素轻度耐药,对地克珠利与托曲珠利中度耐药。结论3个地区的柔嫩艾美耳球虫对供试药物已产生不同程度的耐药性。  相似文献   

8.
1. Six week-old broiler chickens implanted with electroencephalogram (EEG) recording and somatosensory stimulating electrodes were exposed to either 90% argon in air, a mixture of 30% carbon dioxide and 60% argon in air or a mixture of 30% oxygen and 40% carbon dioxide (balance nitrogen) for 2 min, to determine the times to onset of changes in spontaneous EEG and the loss of somatosensory evoked potentials (SEPs) and thus unequivocal loss of consciousness. 2. In addition, after a 2 min exposure to the carbon dioxide-oxygen mixture, some broilers were allowed to recover in air and their EEGs and SEPs were continuously recorded until the return of normal EEG and SEPs. During this period, the time to return of response to comb pinching was also determined in 10 broilers. 3. All broilers exposed to either argon or the carbon dioxide-argon mixture died within 2 min, whereas, only 3 out of 17 broilers died during the 2 min exposure to the carbon dioxide-oxygen mixture. 4. During exposure to argon, unlike the other 2 gas mixtures, the majority of broilers showed high amplitude, low frequency electrical activity in the EEG on average at 10 s. The mean times to onset of EEG suppression were 17, 19 and 40 s after exposure to argon, the carbon dioxide-argon mixture and the carbon dioxide-oxygen mixture, respectively. An isoelectric EEG occurred on average at 58 and 41 s after exposure to argon and the carbon dioxide-argon mixture, respectively. An isoelectric EEG did not occur in broilers which were exposed to the carbon dioxide-oxygen mixture. 5. The SEPs were abolished in broilers on average 32 and 24 s after exposure to argon and the carbon dioxide-argon mixture, respectively. During exposure of broilers to the carbon dioxide-oxygen mixture the SEPs were abolished in the majority of birds on average at 47 s, however, 2 out of 14 birds retained their SEPs for the entire period of 2 min exposure to this gas mixture. 6. During the recovery after exposure to the carbon dioxide-oxygen mixture, response to comb pinching and SEPs returned either at the time of, or soon after, the onset of high frequency electrical activity in the suppressed EEG of broilers. The mean times to return of response to comb pinching and SEPs were 52 and 43 s, respectively. 7. Based on the time to onset of EEG suppression or loss of SEPs, exposure of broilers to either 90% argon in air, or a mixture of 30% carbon dioxide and 60% argon in air, resulted in quicker loss of consciousness than during exposure to a mixture of 40% carbon dioxide, 30% oxygen and 30% nitrogen. The time to return of consciousness after a 2 min exposure to the carbon dioxide-oxygen mixture was also found to be rapid.  相似文献   

9.
A critical challenge for range scientists is to provide input to management decisions for land units where little or no data exist. The disciplines of range science, basic ecology, and global ecology use different perspectives and approaches with different levels of detail to extrapolate information and understanding from well-studied locations to other land units. However, these traditional approaches are expected to be insufficient in the future as both human and climatic drivers change in magnitude and direction, spatial heterogeneity in land cover and its use increases, and rangelands become increasingly connected at local to global scales by flows of materials, people, and information. Here we argue that to overcome limitations of each individual discipline, and to address future rangeland problems effectively, scientists will need to integrate these disciplines successfully and in novel ways. The objectives of this article are 1) to describe the background, historical development, and limitations of current approaches employed by these disciplines; 2) to describe an integrated approach that takes advantage of the strengths and minimizes the weaknesses of these individual approaches; and 3) to discuss the challenges and implications of this integrated approach to the future of range science when climate and human drivers are nonstationary. This integration will be critical for applying range science to the management of specific land units; will contribute to and benefit from the development of general ecological principles; and will assist in addressing problems facing society at regional, continental, and global scales.  相似文献   

10.
Infectious agents are insidious, often changing to adapt to host defenses or treatment advances. Because these challenges will continue, the need to apply standard and transmission-based precautions is important not only in the human hospital setting but in the veterinary clinic setting. In addition, to prevent human infection and potential liability, clinics need to establish program algorithms to prevent disease spread for specific agents or planned procedures to respond to potential nosocomial and zoonotic disease events. These need to be done proactively. Furthermore, more money needs to be dedicated to establish infection control programs and to improve the science of infection control in the veterinary setting.  相似文献   

11.
The purpose of the present study was to determine the prevalence of antibiotic resistance, with special attention to vancomycin, in 104 strains of Enterococcus, which is the sentinel bacterium isolated from dog and cat faeces samples. The phenotypic characterization of the isolates classified them as E. faecium (58%), E. avium (41%) and E. faecalis (1%). Sensitivity testing used the diffusion method according to the recommendations of CASFM (Comite de l'Antibiogramme de la Société Fran?aise de Microbiogie), to oxacillin, amoxycillin, amoxycilin + clavulanic acid, ampicillin, piperacillin, cefoperazone, imipenem, enrofloxacin, ciprofloxacin, ofloxacin, nalidixic acid, tetracycline, lincomycin, erythromicin and vancomycin. Minimum inhibitory concentration (MIC) determination by E test revealed a MIC to vancomycin of between 0.5 microg/ml and 3 microg/ml. All the strains were resistant to nalidixic acid, erythromycin, cefoperazone and oxacillin. We detected resistance to amoxycillin + clavulanic acid in 1.9% of isolates, to amoxycillin in 4.8%, to piperacillin in 13.5%, and to ampicillin in 21.2% of strains. A high prevalence of antibiotic resistance to lincomycin, tetracycline, enrofloxacin, ciprofloxacin and ofloxacin was found in 98.1%, 95.2%, 76.9%, 73.1% and 64.4% of strains, respectively. Resistance to vancomycin was not found, which indicates that there is no transmission risk of vancomycin-resistant enterococcal strains to man or transfer of their resistance genes to other bacteria belonging to the endogenous flora of humans.  相似文献   

12.
The minimal inhibitory concentrations of fifteen antibacterial agents were determined by agar-dilution method against 121 strains of Clostridium perfringens isolated from pigs, cattle and poultry. All strains, regardless of host of origin, were susceptible to avoparcin, furazolidone, monensin, nitrovin, penicillin G, ronidazole and tiamulin and resistant to flavomycin. Poultry strains were also susceptible to carbadox, chloramphenicol, erythromycin and virginiamycin. Bacitracin-resistant poultry strains were susceptible to all tested antibacterial agents except tetracycline, but the bacitracin-resistant cattle strains were polyresistant. Porcine strains were susceptible to bacitracin and bovine strains to carbadox. Carbadox-resistant porcine strains were resistant to erythromycin, lincomycin and tetracycline and susceptible to chloramphenicol. Resistance to erythromycin was associated with resistance to lincomycin. High level erythromycin-lincomycin-resistant strains were susceptible to virginiamycin, but the intermediate level erythromycin-lincomycin-resistant cattle strains were resistant to virginiamycin. Resistance to chloramphenicol or erythromycin-lincomycin was always associated with resistance to tetracycline but the reverse was not always true.  相似文献   

13.
Several experiments were conducted to evaluate the protein quality of various raw and rendered animal by-product meals commonly used in companion animal diets. Six freeze-dried raw animal meals (beef lungs, pork lungs, sheep lungs, pork livers, oceanfish, chicken necks) and 3 rendered animal meals (lamb meal, regular ash poultry by-product meal, and low ash poultry by-product meal) were fed in chick assays to determine Lys and TSAA bioavailability, protein efficiency ratio (PER), and net protein ratio (NPR). Each experimental diet was offered to 4 replicates of 5 chicks per pen in all growth assays. Furthermore, each animal by-product meal was fed to mature White Leghorn roosters for determination of true AA digestibility. All freeze-dried, raw animal meals were offered to 5 replicate roosters, and all rendered animal meals were offered to 4 replicate roosters. Most raw animal meals exhibited moderate to high protein quality. Lysine bio-availabilities ranged from 86 to 107% and 70 to 99% for raw and rendered animal meals, respectively. Bio-availability of TSAA ranged from 64 to 99% and 61 to 78% for raw and rendered animal meals, respectively. The PER values ranged from 2.83 to 4.03 and 2.01 to 3.34 for raw and rendered animal meals, respectively. The NPR values ranged from 3.83 to 4.8 and 3.05 to 4.12 for raw and rendered animal meals, respectively. Despite a numeric increase in NPR vs. PER values, the overall ranking of animal meals remained similar. Lamb meal had the poorest PER and NPR values, and pork lungs had the greatest values. Total essential AA digestibility and total AA digestibility ranged from 93.6 to 96.7 and 90.3 to 95.5%, respectively, for raw animal meals and 84.0 to 87.7 and 79.2 to 84.8%, respectively, for rendered animal meals. Rendered animal meals generally had lower protein quality than raw animal meals, with lamb meal consistently having the poorest protein quality and pork livers having the greatest protein quality.  相似文献   

14.
采集猪颌下淋巴结,猪肠系膜淋巴结,牛颌下淋巴结和牛肠系膜淋巴结各200份,使用改良罗氏培养基进行分离培养和传代培养,通过进行生长特性试验、生化鉴定试验和鉴别培养基生长试验对所分离出的分枝杆菌进行菌型鉴定。结果显示:猪颌下淋巴结中分离出耻垢分枝杆菌4株,鸟分枝杆菌4株,胞内分枝杆菌2株,胃分枝杆菌2株,蟾蜍分枝杆菌1株,龟分枝杆菌龟亚种杆菌1株;猪肠系膜淋巴结未分离出非结核分枝杆菌;牛肠系膜淋巴结分离出瘰疬分枝杆菌2株,加地斯分枝杆菌1株;牛肠系膜淋巴结分离出,瘰疬分枝杆菌5株,金色分枝杆菌2株,戈登分枝杆菌2株,蟾蜍分枝杆菌2株。猪、牛的感染率均为3.5%。  相似文献   

15.
Factors thought to influence monthly body weight and average daily gain of 122 first and second generation Canadian Holstein calves aged six to 24 months were studied. All factors (generation, sex, parity, season, age and year) studied accounted for 55.9 to 71.2% and 35.6 to 69.1% of the variation in body weight and average daily gain respectively. Parity, year and generation were the most important factors influencing all traits and accounted for 34.4 to 64.3% and 22.9 to 66.8% of the variation in body weight and average daily gain. Least squares means were, for body weight 144.2, 222.6, 330.5 and 377.9 kg at six, 12, 18 and 24 months and for average daily gain 0.42, 0.37, 0.50 and 0.39 kg at six to nine, nine to 12, 12 to 18 and 18 to 24 month intervals. It was concluded that offspring of Canadian Holsteins in this environment under adequate management and nutrition will be of adequate size for heifers to calve under 30 months of age and steers to reach 400 kg slaughter weight in 24 months.  相似文献   

16.
Total litter weight weaned at 120 d postpartum per ewe lambing is often believed to be a measure of range ewe productivity. Genetic correlations for litter weight weaned at 120 d with prolificacy, growth, and wool traits for Columbia, Polypay, Rambouillet, and Targhee sheep were estimated using REML with animal models. Observations per breed ranged from 5,140 to 7,083 for litter weight weaned, from 5,140 to 7,095 for prolificacy traits, from 7,750 to 9,530 for growth traits, and from 4,603 to 18,443 for wool traits. Heritability estimates for litter weight weaned were low and ranged from 0.02 to 0.11. Fraction of variance due to permanent environmental effects averaged 0.05 and, due to effects of mates, averaged 0.01. Estimates of genetic correlations with litter weight weaned varied from breed to breed. The ranges were as follows: 0.42 to 0.65 with litter size born, 0.80 to 0.99 with litter size weaned, -0.22 to 0.28 with birth weight, -0.07 to 0.23 with average daily gain to weaning, -0.56 to 0.19 with fleece weight, -0.15 to 0.02 with fleece grade, and -0.11 to 0.08 with staple length. Results suggest that, if selection were practiced on litter weight weaned, the average correlated responses would be expected to be favorable or neutral for prolificacy, growth, and wool traits although responses might vary from breed to breed.  相似文献   

17.
A study was conducted to determine the antibiotic resistance and biochemical characteristics of 2690 Salmonella strains belonging to 52 serovars and isolated from environmental and feed samples from 270 turkey flocks in Canada. Resistance of the Salmonella strains to the aminoglycoside antibiotics varied widely; none of the strains were resistant to amikacin, 14.2% were resistant to neomycin, 25.8% were resistant to gentamicin, and 27.7% of the strains were resistant to kanamycin. Most strains (97.6%) were resistant to the aminocyclitol, spectinomycin. Regarding resistance to the beta-lactam antibiotics, 14.3% and 14.4% of the strains were resistant to ampicillin and carbenicillin, respectively, whereas only 5 (0.2%) of the strains were resistant to cephalothin. None of the strains were resistant to the fluoroquinolone ciprofloxacin or to polymyxin B. Resistance to chloramphenicol and nitrofurantoin was found in 2.4% and 7% of the strains, respectively. Only 1.7% of the strains were resistant to the trimethoprimsulfamethoxazole combination, whereas 58.1% were resistant to sulfisoxazole. Thirty-eight percent of the strains were resistant to tetracycline. Salmonella serovars differed markedly in their drug resistance profiles. Biochemical characterization of the Salmonella showed that the S. anatum, S. saintpaul and S. reading serovars could be divided into distinct biotypes.  相似文献   

18.
Automatic milking systems have been shown to change the behaviour of cows. Because pre-determined milking and feeding times are eliminated, the cows must establish their own daily routine. They have to adapt to being milked according to their lactation. There are, however, indications that not all cows adapt well to the automatic system. Some herd members seem to have inhibitions about entering the milking stall. Too many cows per milking stall and a blocked milking system intensify the situation. Therefore, the cows must either be forced or attracted by food to enter the milking stall. Altogether some cows appear to be more stressed. Furthermore, the human-animal relationship changes due to the new work content. There is less manual work, more observation, and more computer data. The farmer needs to be well educated and must establish a new management program. If care is insufficient, if some herd members are less frequently milked, and if measures to reduce stress are not taken, it is clear that welfare problems could arise. Compared to milk quality and milk hygiene, technical solutions and regulations by law are not as important. Ethological knowledge must be taken into account if automatic milking is to be advantageous for both cow and man.  相似文献   

19.
Pyothorax is a serious disease process which requires both medical and surgical intervention. Late recognition, management problems, and likely recurrence make successful treatment difficult and often frustrating. Aims of therapy should be to avoid undue stress to the patient, to relieve respiratory distress by thoracocentesis, to eliminate infectious agents with antimicrobials, to remove pleural exudate, and to provide supportive care. Close monitoring of the patient is necessary to prevent iatrogenic complications such as pneumothorax, hemothorax, hypothermia, or hypoproteinemia. Exploratory thoracotomy for removal of granulomatous material and fibroelastic pleural "peels" is occasionally necessary to resolve compressive cardiopulmonary lesions.  相似文献   

20.
本文全面综述了世界羊毛主产国羊毛生产和贸易现状,探讨了国际羊毛市场的供求关系,从而提出我国今后羊毛发展及贸易的对策:加强品种选育提高;建立优质细毛羊产业化生产技术体系;加强羊毛产销管理;加大资金投入,搞好宏观调控;高度重视羊毛产品质量安全问题,迅速建立我国的“绿色贸易壁垒”;恢复和发展草原生态平衡,实现羊毛业可持续发展。  相似文献   

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