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991.
W Rabsch A Liesegang H Tsch?pe 《Berliner und Münchener tier?rztliche Wochenschrift》2001,114(11-12):433-437
The Paul Ehrlich Institute, Langen, in Germany has been licensed different live vaccines of S. Typhimurium and S. Enteritidis for use in the veterinary medicine since I the 90s. The Robert Koch Institute has established a lab-based surveillance system for these live vaccine strains for an evaluation of recent public health safety. Since 2000 all strains of S. Typhimurium and S. Enteritidis from humans were investigated in respect to their phage types and other vaccine markers. 3676 S. Typhimurium strains and 4489 S. Enteritidis strains mainly from Salmonellose patients were investigated after phage typing according to their auxotrophic or antibiotic resistance markers. The live vaccine strains of Zoosaloral, TAD Salmonella vacT or TAD Salmonella vacE and Salmovac SE could not be found from infections in humans. 相似文献
992.
F. RODRÍGUEZ G. A. RAMÍREZ A. S. RAMÍREZ H. J. BALL A. ESPINOSA
DE LOS MONTEROS A. FERNNDEZ 《Zoonoses and public health》2002,49(5):226-229
Samples from the mammary tissue of 14 lactating goats (12 naturally infected and two experimentally infected) were examined for the presence of Mycoplasma agalactiae. A monoclonal antibody (5G12) was applied to formalin‐fixed, paraffin‐wax‐embedded sections and labelled by the avidin–biotin peroxidase complex (ABC) method. Histological examination of tissue sections revealed strong immunoreactivity in all animals included in the study. Mycoplasma agalactiae antigen was mainly detected in the cellular debris at the periphery of purulent exudates present within lactiferous sinuses, and lactiferous and interlobular ducts. In addition, M. agalactiae organisms appeared in the cytoplasm of the epithelium of ducts, and in infiltrating macrophages and neutrophils within the ducts, alveoli, interstitial tissue and regional lymph node sinuses. It is concluded that this monoclonal antibody‐based immunohistochemical technique is an efficient and specific method for the post‐mortem detection of M. agalactiae in cases of clinical mastitis as well as being a useful tool for the study of the route of infection and cellular types involved during mastitis caused by this organism. 相似文献
993.
关于饲料中胆碱含量化学分析值的资料很多。饲料中的胆碱含量因饲料种类、出产国别、出产年份等的不同而不同。问题还不止于此,据发现,测定饲料中胆碱含量时所用的技术也不能给出充分可靠的结果,因而需要一种新技术。 相似文献
994.
Presentation of postweaning Escherichia coli diarrhea in southern Ontario, prevalence of hemolytic E. coli serogroups involved, and their antimicrobial resistance patterns 总被引:1,自引:0,他引:1
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Rocio Amezcua Robert M. Friendship Catherine E. Dewey Carlton Gyles John M. Fairbrother 《Canadian journal of veterinary research》2002,66(2):73-78
Post-weaning Escherichia coli diarrhea (PWECD) in Ontario was investigated using a case-control study involving 50 Ontario nurseries. The clinical signs and the impact on productive parameters were determined by means of a producer survey. The hemolytic E. coli serogroups involved in PWECD (O149:K91:K88) were examined in this study. Based on a polymerase chain reaction test, the hemolytic E. coli from 82% of the case herds were positive for 3 enterotoxins (STa, STb, and LT), those from 12% of the case herds were positive for STb and LT only, and those from one herd (6%) were positive for 3 enterotoxins, as well as for verotoxin and F18 pili. The E. coli involved in disease were resistant to multiple antibiotics. Case farms commonly used a wide variety of antibiotics either in the feed or water, or as injectable drugs. The most common antibiotic used to treat PWECD on the study farms was apramycin, but evidence of resistance to this antibiotic was noted. The PWECD problem was commonly seen within a week of weaning but onset of diarrhea was reported as late as the grower-finisher stage. Growth rate was poorer in case herds and mortality was higher than in control herds, demonstrating that PWECD is an economically important disease in Ontario. 相似文献
995.
Application and crop safety parameters for soil fumigants 总被引:2,自引:0,他引:2
A. S. Csinos T. M. Webster D. R. Sumner A. W. Johnson C. C. Dowler K. W. Seebold 《Crop Protection》2002,21(10):973-982
Metam sodium alone and in combination with 1,3-dichloropropene plus 17% chloropicrin (1,3-D+C-17) were evaluated under polyethylene mulch film as alternatives for methyl bromide in tobacco and tomato transplant production for both efficacy against pests and crop safety. Eight different weed species, 10 genera or species of fungi and several agronomic criteria were evaluated at three different sites. In general both the metam sodium alone and in combination with 1,3-D+C-17 were highly efficacious when compared to methyl bromide. Short polyethylene film retention times and short aeration times resulted in poor stands and poor crop vigor while relatively long polyethylene film retention times and long aeration periods at the same rates typically resulted in high stand counts and vigor. Combination treatments were more phytotoxic to germinating seed of tobacco and tomato. Vigor and stand counts of the seedlings were higher as aeration time increased, suggesting phytotoxic residues dissipate with time. Method of application of metam sodium, either injected with chisels or sprayed onto the soil surface and incorporated with a tractor-powered tiller alone or co- applied with 1,3-D+C-17 chisel injected, did not affect the efficacy of the treatments. Caution regarding phytotoxicity must be exercised when seeding into soil fumigated with metam sodium alone or combined with 1,3-D+C-17. Additional work will be required to establish safety periods required prior to transplanting crops into fumigated soil. 相似文献
996.
997.
998.
CONSTANCE M. E. GARRETT 《Plant pathology》1986,35(1):114-119
In a field trial to determine whether the rootstock influenced the susceptibility of cherry cultivars to bacterial canker three cultivars (Napoleon, Roundel and JI 14039), each grafted on two rootstocks (F 12/1 and Colt), were subjected to natural infectionand to inoculation with three bacterial canker pathogens (Pseudomonas syringae pv. morsprunorum races 1 and 2 and P. syringae pv. syringae). Inoculations were made through leaf scars and through wounds. The high susceptibility of Napoleon and high resistance of JI 14039 were confirmed. Napoleon was more susceptible to inoculation through branches when on F12/1 than when on Colt but the reverse was true for leaf scar inoculations. JI14039 was more susceptible to race 1 inoculated through leaf scars when grown on F12/1 than when on Colt. No rootstock/scion interaction was detected with Roundel.
The complexity of the relationships between the pseudomonad pathogens and their cherry hosts is briefly discussed. 相似文献
The complexity of the relationships between the pseudomonad pathogens and their cherry hosts is briefly discussed. 相似文献
999.
Two-year field trials with winter wheat cultivars Batis and Toronto were conducted in Southern Bavaria, Germany, to investigate the possible causes of cultivar differences in response to N supply varying in total amount and time of application. Cultivar-related differences in grain yields were observed in treatments with low and medium N supply. High doses of N supply resulted in grain yield adjustment or grain yield advantage for cv. Toronto. The results of this study revealed a consistent, genotypic pattern in response to N fertilization in spite of strong seasonal effects. Systematic modifications in canopy growth rates in response to N supply were of particular relevance and a main factor for differences in tillering intensity resulting in modified stand densities. In the present study, cultivar differences in spike development and interactions with N supply related more to abortion than to initiation processes for number of spikelets and number of flowers per spikelet. High grain density (grains per m2) of cv. Toronto was evident during reproduction stages even under conditions of medium N supply. However, decreased growth rates during the later part of grain filling in combination with low 1000 grain weight, which was barely modified by N fertilization, allowed only partial utilization of this potential. It is assumed that sink limitations were of particular relevance for grain yield development in cv. Toronto, while cv. Batis combined a less intense response to N supply with more stability in the development of grain yield components. 相似文献
1000.
Morphological characterization of the interaction between Diplocarpon rosae and various rose species
Blackspot, caused by Diplocarpon rosae , is the most severe and ubiquitous disease of garden roses, but information is lacking about genotype-specific forms of resistance and susceptibility of the host. Macro- and microscopic analyses of 34 rose genotypes with a defined monoconidial culture black spot inoculum identified susceptible and resistant rose genotypes and further genotype-specific subdivisions, indicating the presence of partial forms of resistance and different resistance mechanisms. In total, eight interaction types were characterized, five representing compatible (types 1–5) and three representing incompatible interactions (types 6–8). The incompatible interactions were characterized by the lack of any visible fungal structures beneath the cuticle (type 8), single-cell necroses (type 7) or necroses of larger cell clusters (type 6), the latter two types with penetration hyphae and haustoria in epidermal cells. 相似文献