The Low-Temperature-Induced Viable-But-Nonculturable State Affects the Virulence of Ralstonia solanacearum Biovar 2     

van Overbeek LS  Bergervoet JH  Jacobs FH  van Elsas JD 《Phytopathology》2004,94(5):463-469

ABSTRACT The physiology and virulence of Ralstonia solanacearum biovar 2 strain 1609, kept in water at 4 and 20 degrees C, were studied. At 20 degrees C, total cell and plate count (colony forming units; CFU) numbers were similar, between log 5.03 and log 5.55 CFU, and log 5.03 and log 5.51 cells per ml, at days 0 and 132, respectively. However, CFU in the cultures kept at 4 degrees C dropped from log 6.78 CFU/ml at day 0 to below detection after 84 days. The presence of catalase in the agar resulted in higher CFU, and at day 84, log 1.95 CFU/ml still was detectable. No colonies were observed at day 125. The presence of viable-but-nonculturable (VBNC) cells in the 4 degrees C cultures was confirmed using SYTO9 viability staining. Viable cell numbers were log 1.77 higher than CFU on plates with catalase. At day 84 and after 125 days, log 3.70 viable cells per ml still were present. Shifts in subpopulations differing in viability were found by flow cytometric sorting of 4 degrees C-treated cells stained with SYTO9 (healthy) and propidium iodide (PI; compromised). The SYTO9-stained cell fractions dropped from 99 to 39%, and the PI-stained fractions increased from 0.7 to 33.3% between days 0 and 125. At 20 degrees C, the SYTO9-stained fraction remained stable at 99% until day 132. SYTO9-stained cells sorted from 4 degrees C cultures at day 100 were injected into tomato plants. Upon incubation for 30 days, these plants did not show wilting. However, more than log 4.19 CFU and log 8.17 cells were recovered from these plants. Cells from colonies isolated from the nonwilted plants did not regain their virulence as demonstrated by subsequent injection into several new sets of tomato plants. Cells from 4 degrees C cultures injected at day 125 were not able to cause wilting of, or proliferate in, tomato plants. The threat posed by VBNC R. solanacearum cells upon incubation at 4 degrees C was thus ephemeral because cells lost their capacity to cause disease after 125 days.  相似文献   

Effects of ovariohysterectomy on canine blood neutrophil respiratory burst: a chemiluminescence study   总被引：1，自引：0，他引：1  

Väisänen M  Lilius EM  Mustonen L  Raekallio M  Kuusela E  Koivisto M  Vainio O 《Veterinary surgery : VS》2004,33(5):551-556

OBJECTIVE: To examine blood neutrophil counts and luminol-enhanced chemiluminescence (CL) responses in dogs undergoing ovariohysterectomy (OH), premedicated with 2 different drugs. STUDY DESIGN: Randomized clinical study. ANIMALS: Forty-two healthy client-owned bitches. METHODS: Dogs had OH under isoflurane anesthesia with either acepromazine or medetomidine, both in combination with butorphanol, administered as preanesthetic medication. Blood samples were collected when the dog was admitted, at the end of surgery, and the next day (approximately 20 hours after surgery). Blood neutrophils were counted automatically, and neutrophil oxidative activity was assessed by measuring blood CL responses (induced by opsonized zymosan and enhanced by luminol) at 37 degrees C for 40 minutes. RESULTS: Number of circulating neutrophils was significantly increased the day after surgery reflected by enhanced blood CL responses. Neutrophil CL, however, was not significantly altered. No significant differences were detected for perioperative Polymorphonuclear neutrophil (PMN) characteristics between the 2 preanesthetic regimens. CONCLUSIONS: In conclusion, despite clearly increasing the number of circulating neutrophils, OH did not significantly affect neutrophil respiratory burst, as measured by whole-blood CL responses. CLINICAL RELEVANCE: Surgical operation of moderate intensity (e.g., OH) did not significantly alter one of the important immune functions, neutrophil oxidative activity. Further studies are warranted to confirm the significance of this finding, and to assess the value of following this variable in different animal patient populations.  相似文献   

Treatment of CVMP-affected fibrosarcoma not supported     

Hornix L 《Tijdschrift voor diergeneeskunde》2004,129(9):314

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Funding opportunities for research and graduate education: how the NIH can help you     

Grieder FB  Whitehair LA 《Journal of veterinary medical education》2005,32(3):314-317

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Effect of prepartum intramammary treatment with pirlimycin hydrochloride on prevalence of early first-lactation mastitis in dairy heifers     

Middleton JR  Timms LL  Bader GR  Lakritz J  Luby CD  Steevens BJ 《Journal of the American Veterinary Medical Association》2005,227(12):1969-1974

OBJECTIVE: To determine whether prepartum intramammary treatment of dairy heifers with pirlimycin hydrochloride would reduce the prevalence of intramammary infection (IMI) and lower the somatic cell count (SCC) during early lactation or improve 305-day mature equivalent milk production. DESIGN: Prospective clinical trial. ANIMALS: 183 Holstein-Friesian heifers (663 quarters) from 2 dairy farms. PROCEDURE: Heifers were assigned to treatment and control groups. Treated heifers received a single 50-mg dose of pirlimycin in each mammary quarter approximately 10 to 14 days prior to parturition. Prepartum mammary gland secretions and postpartum milk samples were collected for bacterial culture. Postpartum milk samples were also collected for determination of SCC or California mastitis testing and were tested for pirlimycin residues. Mature equivalent 305-day milk production data were recorded. RESULTS: Treated heifers in herd A had a higher overall cure rate, higher cure rates for IMI caused by coagulase-negative staphylococci (CNS) and Staphylococcus aureus, lower SCC, and lower prevalence of chronic IMI, compared with control heifers. Treated heifers in herd B had a higher overall cure rate and cure rate for IMI caused by CNS, compared with control heifers, but postpartum California mastitis test scores and prevalence of chronic IMI did not differ between groups. Mature equivalent 305-day milk production did not differ between herds or treatment groups. No pirlimycin residues were detected in postpartum milk samples. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that prepartum treatment of dairy heifers with pirlimycin may reduce the prevalence of early lactation IMI, particularly IMI caused by CNS, without causing pirlimycin residues in milk.  相似文献   

HÆMOGLOBINURIA OF CALVES IN THE SOUTH-WEST OF WESTERN AUSTRALIA     

Leo W.  Mahaffey B.V.Sc.  H. W. Bennetts  D.V.Sc.† A. F. Flood  M.E.C.V.S.‡ 《Australian veterinary journal》1942,18(5):205-208

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Pyothorax in 26 cats: clinical signs, laboratory results and therapy (2000-2007)     

Ottenjann M  Lübke-Becker A  Linzmann H  Brunnberg L  Kohn B 《Berliner und Münchener tier?rztliche Wochenschrift》2008,121(9-10):365-373

Common historical findings in 26 cats with pyothorax were dyspnea (85%), lethargy (65%), and anorexia (62%), common clinical findings were dyspnea (89%), tachypnea (73%), fever (39%), and hypothermia (27%). Frequent laboratory abnormalities were leukocytosis (68%) with a left shift (100%), anemia (65%), hypoalbuminemia (91%), hyperglobulinemia (86%), hyperbilirubinemia (60%) as well as azotemia (52%). The thoracic effusion was purulent in all cats, the thoracic fluid evaluation (n = 19) met the criteria for an inflammatory exudate (protein 32-63 g/l, median 44; cell count 54.4-390 x 10(9)/l, median 100). Cytological analysis revealed bacteria in 21 of 24 cats. From 16 cats 13 different genera were isolated, 5 cultures were without bacterial growth. In 12.5% of the cats a single population of bacteria was identified, and in 87.5% a mixture of 2-4 different bacterial species were cultured. Obligate anaerobic bacteria were the most common isolates (70%) followed by facultative anaerob (22.5%) and aerob growing (7.5%) bacteria. Bacterial culture most often yielded Fusobacteria spp., Prevotella spp., Pasteurella spp., Porphyromonas spp. and Bacteroides spp. Three cats were euthanized at the day of presentation. A thoracic lavage was performed in 22 cats; mechanical complications with the chest tubes occured in 4 cats. Thoracotomy was performed in 2 cats. Of the 23 treated cats 17 survived (74%).  相似文献   

Methicillin-resistant Staphylococcus aureus (MRSA) isolated from small and exotic animals at a university hospital during routine microbiological examinations     

Walther B  Wieler LH  Friedrich AW  Hanssen AM  Kohn B  Brunnberg L  Lübke-Becker A 《Veterinary microbiology》2008,127(1-2):171-178

Clinical specimens of small animals (n=869) were screened for the occurrence of methicillin-sensitive and methicillin-resistant Staphylococcus aureus (MSSA; MRSA) during routine microbiological examinations, and results were confirmed by a multiplex PCR strategy. The genetic relatedness of all mecA-positive S. aureus isolates was further investigated by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), PCR for Panton-Valentine leukocidine genes (PVL) and staphylococcal cassette chromosome mec-typing (SCCmec). A total of 61 S. aureus isolates were found during a 20-month period of investigation, 27 (44.3%) of them harbouring the mecA gene for methicillin-resistance. The majority of MRSA were isolated in specimens from dogs (n=18) and cats (n=4). One guinea pig and one rabbit were found to be positive for an MRSA infected site. Similarly, three exotic animals, a turtle, a bat and a parrot, were found to be infected with MRSA. PFGE and MLST analysis revealed a certain genotype ("A" and "A-1") dominating the isolate collection (23 of 27). Furthermore, one isolate showed homologous PFGE pattern to the German epidemic strain Barnim ("BE") and another one ("BE-1") was considered to be closely related. A third genotype ("B") was detected in two cases. Two different sequence types (ST) were identified among the 27 MRSA isolates. PFGE type "A" and both strains related to the Barnim epidemic strain were assigned to ST22, whereas ST239 was associated to PFGE profile "B". The present data show that certain MRSA genotypes are capable of infecting a wide spectrum of small and exotic animals, especially in clinical facilities.  相似文献   

Fifty years of Equine Veterinary Journal          下载免费PDF全文

Leo Jeffcott 《Equine veterinary journal》2018,50(4):421-422

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Ausfluszzeitermittlung bei Stauwerken     

Leo Hausta 《Forstwissenschaftliches Centralblatt》1924,46(10):517-534

Ohne Zusammenfassung  相似文献