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71.
A Lillehaug B Bergsj? J Schau T Bruheim T Vik?ren K Handeland 《Acta veterinaria Scandinavica》2005,46(1):23-32
Faecal samples were collected, as part of the National Health Surveillance Program for Cervids (HOP) in Norway, from wild red deer, roe deer, moose and reindeer during ordinary hunting seasons from 2001 to 2003. Samples from a total of 618 animals were examined for verocytotoxic E. coli (VTEC); 611 animals for Salmonella and 324 animals for Campylobacter. A total of 50 samples were cultivated from each cervid species in order to isolate the indicator bacterial species E. coli and Enterococcus faecalis/E. faecium for antibiotic resistance pattern studies. Salmonella and the potentially human pathogenic verocytotoxic E. coli were not isolated, while Campylobacter jejuni jejuni was found in one roe deer sample only. Antibiotic resistance was found in 13 (7.3%) of the 179 E. coli isolates tested, eight of these being resistant against one type of antibiotic only. The proportion of resistant E. coli isolates was higher in wild reindeer (24%) than in the other cervids (2.2%). E. faecalis or E. faecium were isolated from 19 of the samples, none of these being reindeer. All the strains isolated were resistant against one (84%) or more (16%) antibiotics. A total of 14 E. faecalis-strains were resistant to virginiamycin only. The results indicate that the cervid species studied do not constitute an important infectious reservoir for either the human pathogens or the antibiotic resistant microorganisms included in the study. 相似文献
72.
Bhupender Singh Fernando Saravia Renée B?ge Heriberto Rodríguez-Martínez 《Acta veterinaria Scandinavica》2005,46(1):1-12
Hormonal asynchronies during oestrus, related to the presence of suprabasal plasma-progesterone (P4) concentrations and a delayed ovulation, interfere with the fertility of repeat-breeder heifers (RBH). Since tubal dysfunction can occur in connection with hormonal asynchronies and constrained availability of fertile spermatozoa at the time of ovulation, the present study tested the hypothesis that frequent sperm deposition from onset of oestrus to ovulation may improve pregnancy rates in RBH. Five RBH and five virgin heifers (VH; controls) were repeatedly artificially inseminated (AI) at 6 h intervals from onset of oestrus to spontaneous ovulation. Hormone analyses revealed suprabasal P4 concentrations and a delay in the occurrence of the luteinising hormone (LH) surge, but a normal cortisol profile in RBH. Compared with controls, RBH presented longer interval from onset of oestrus to ovulation, and therefore, received more AIs. Pregnancy rates in RBH reached control levels (60%; NS), indicating that the hypothesis might be correct. Pregnancy rates in VH were below the expected range, presumably attributed to a deleterious influence of the frequent handling. The study suggests that pregnancy rates can be improved in RBH by frequent AI in relation to spontaneous ovulation. However, this practice of repeated manipulations, while seeming not to show adverse effects, lacks practicality for routine use. 相似文献
73.
Patrick Rehmann Andrea Gr?ne Bruno Gottstein Jürg V?llm Heinz Sager Martin Janovsky Luca N Bacciarini 《Journal of veterinary diagnostic investigation》2005,17(2):183-186
Five animals in a colony of cynomolgus monkeys (Macaca fascicularis) died or were euthanatized because of alveolar echinococcosis, during a period of 5 years. The remainder of the colony was screened for possible infection with Echinococcus multilocularis, using serology and ultrasonography. A total of 46 animals out of a group of 55 were examined. The presence of anti-Em2 antibodies analyzed with enzyme-linked immunosorbent assay was demonstrated in 3 monkeys. In 2 of these 3 monkeys, multilocular structures compatible with metacestodal cysts in the liver were identified, using ultrasonography. The presence of alveolar echinococcosis was subsequently confirmed at postmortem examination in 1 animal. The other animals are still alive. Two other monkeys were negative in the serological examination but had cystic structures in the liver, which were identified as bile duct cysts at postmortem examination in 1 animal. The other monkey is still alive. These findings suggest that serology for antibodies against the Em2 antigen may represent a useful method in identifying animals that might be infected with E. multilocularis and are therefore at risk of developing fatal alveolar echinococcosis. 相似文献
74.
Shohei MATSUURA Shigeru HOSHINO Hideaki HAYASHI Tetsuyuki KOHGUCHI Kyoji HAGIWARA Toshihiro OMURA 《Journal of General Plant Pathology》2002,68(1):99-102
DAS-ELISA proved to be reliable enough to detect a latent infection by Tomato spotted wilt virus (TSWV) in asymptomatic stock plants of chrysanthemum. A high density of Frankliniella occidentalis, the predominant vector, in the presence of latently infected stock plants resulted in a high incidence of disease in the chrysanthemum
production field. The incidence of disease was low when the vector thrips were not abundant in spite of the presence of latently
infected stock plants. These results suggest that an infestation of the vector thrips causes severe secondary spread of TSWV
originating from latently infected stock plants in chrysanthemum production fields.
Received 27 July 2001/ Accepted in revised form 27 November 2001 相似文献
75.
REN Yu-sheng WU Zong-gui CUI Fang JIA Guo-liang YU Shi-qing TANG Chao-wu LI Bo 《园艺学报》2002,18(11):1377-1380
AIM: To investigate the effects of platelet-derived growth factor on DNA and collagen protein synthesis in human vascular fibroblasts. METHODS: In the present experiment, the human vascular fibroblasts were cultured and effects of platelet-derived growth factor-BB on DNA and collagen protein synthesis in human vascular fibroblasts were observed by using [3H]-TdR incorporation and [3H]-proline incorporation in vitro. RESULTS: Platelet-derived growth factor-BB significantly promoted NDA synthesis and collagen protein synthesis of quiescent human vascular fibroblasts, with a maximal response at a concentration of 30μg·L-1at 24 h and 36 h, respectively. CONCLUSION: Platelet-derived growth factor-BB promotes DNA and collagen protein synthesis in cultured human vascular fibroblasts. 相似文献
76.
77.
Bo?ena Bukowska Katarzyna GoszczyńskaWirgiliusz Duda 《Pesticide biochemistry and physiology》2003,77(3):92-98
The effects of exposure of human erythrocytes to different concentrations of 4-chloro-2-methylphenoxyacetic acid (MCPA) and its metabolite—2,4-dimethylphenol (2,4-DMP) were studied. The investigations concerned mainly the content of glutathione (GSH and GSSG), glutathione peroxidase (GSH-Px), glutathione transferase (GST), and the level of adenine energy charge (AEC). Reactive oxygen species (ROS) such as hydroxyl radical, superoxide anion, hydrogen peroxide, and nitric oxide are produced during normal processes in the cell. Under normal conditions, antioxidant systems of the cell minimize damage caused by ROS. When ROS generation increases to an extent that it overcomes the cellular antioxidant systems, the result is oxidative stress. We observed that MCPA and 2,4-DMP decreased the level of GSH in erythrocytes in comparison with control. MCPA did not affect glutathione peroxidase and glutathione transferase activity, while 2,4-DMP increased their activity. 2,4-DMP decreased the level of ATP and increased the content of ADP and AMP, leading to the fall of the level of AEC. MCPA and 2,4-DMP transform hemoglobin into methemoglobin, thus preventing oxygen transport. Comparison of the toxicity of MCPA and 2,4-DMP revealed that the most prominent changes occurred in human erythrocytes incubated with 2,4-DMP. 相似文献
78.
Eiji Tanaka Chihiro Tanaka Atsushi Ishihara Yasumasa Kuwahara Mitsuya Tsuda 《Journal of General Plant Pathology》2003,69(1):1-6
Aciculosporium take (Ascomycota; Clavicipitaceae) is a causal agent of witches' broom of
bamboo plants. The symptoms of this disease are believed to be induced by plant
hormones, particularly auxins. Indole-3-acetic acid (IAA) was identified in
cultures of this fungus in an l-tryptophan-supplemented liquid medium.
IAA production was confirmed on 30 isolates of A. take from various
hosts and locations at levels up to 1 mg/l. The biosynthetic pathway of
IAA in A. take culture was examined by analyzing intermediate products
and by feeding experiments. The results showed that the indole-3-pyruvic acid
pathway (l-tryptophan → indole-3-pyruvic acid → indole
acetaldehyde → IAA) was the dominant pathway in A. take.
Received: June 3, 2002 / Accepted: July 25, 2002 相似文献
79.
Hiromitsu Furuya Tsutomu Matsumoto Shin-ichi Fuji Hideki Naito 《Journal of General Plant Pathology》2003,69(2):115-119
Rice seedling growth, estimated by plant height and root development and discoloration, was better in pasteurized soil than
in unpasteurized soil obtained from a flooded rice field. Rice seedlings also grew better in sterilized soil modified by adding
roots harvested from the pasteurized soil than in soil modified by adding roots harvested from the unpasteurized soil. The
results demonstrate that seedling growth in the rice field soil was inhibited by soil microorganisms, even though no typical
symptoms such as seedling blight or damping-off appeared. Pythium aristosporum is suggested to be involved in the inhibition. Thus, it appears that inconspicuous restraint of rice seedling growth could
occur in soils of rice paddy fields.
Received: May 20, 2002 / Accepted: October 16, 2002
Acknowledgments The authors thank Dr. T. Ichitani, former professor at Osaka Prefectural University, for providing an isolate of Pythium aristosporum for comparison, and Mr. Mitsuaki Sato of Akita Prefectural College of Agriculture for technical assistance. 相似文献
80.