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931.
Generalized cowpox infection in the Patagonian cavy may represent a threat to the health of immunocompromised persons. We report the first case of cowpoxvirus infection in the Patagonian cavy in an educational animal park. The mara developed extensive pox lesions, shedding large amounts of viral particles. The ending of vaccination programmes against smallpox in the late 1970's may lead to an increase in susceptibility of humans to zoonotic poxviruses. 相似文献
932.
Formulation with CpG ODN enhances antibody responses to an equine influenza virus vaccine 总被引:3,自引:0,他引:3
Lopez AM Hecker R Mutwiri G van Drunen Littel-van den Hurk S Babiuk LA Townsend HG 《Veterinary immunology and immunopathology》2006,114(1-2):103-110
Previous studies have shown that protection against equine influenza virus (EIV) is partially mediated by virus-specific IgGa and IgGb. In this study we tested whether addition of a CpG ODN formulation to a commercial killed virus vaccine would enhance EIV-specific IgGa and IgGb antibody responses, and improve protection against an experimental EIV challenge. Thirty na?ve horses were assigned to one of three groups and vaccinated as follows: 10 were given vaccine (Encevac TC4, Intervet Inc.) alone, 10 were given vaccine plus 0.25 mg CpG ODN 2007 formulated with 30% Emulsigen (CpG/Em), and 10 controls were given saline. All horses were challenged with live virus 12 weeks after the final vaccination. Antibody responses were tested by single radial hemolysis (SRH) and ELISA, and protection was evaluated by determination of temperature, coughing, and clinical scores. Killed virus vaccine combined with CpG/Em induced significantly greater serologic responses than did the vaccine alone. All antibody isotypes tested increased after the addition of CpG/Em, although no shift in relative antibody isotypes concentrations was detected. Vaccination significantly improved protection against challenge but the differences between the two vaccine groups were not statistically significant. This study is the first demonstration that CpG/Em enhances antigen-specific antibody responses in horses and supports its potential to be used as an adjuvant for vaccines against equine infections. 相似文献
933.
van den Hoven R Duvigneau JC Hartl RT Gemeiner M 《Veterinary research communications》2006,30(8):921-928
On four occasions, four horses with heaves and four horses with small airway inflammatory diseases inhaled 0.9% saline based
aerosol mixtures with or without lipopolysaccharides (LPS). Prior to the first saline and LPS inhalation, horses were untreated,
while three and a half days prior to the third and forth inhalation horses had received 0.8 μ g/kg clenbuterol intravenously
twice daily.
The messenger RNA (mRNA) expression of tumour necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-4, IL-6, IL-8, IL-10 and
interferon- γ (IFN- γ) was investigated by RT-PCR, all of which were expressed in the white blood cells of samples collected.
Inhalation of LPS only changed the cytokine expression profile of IL-10, IL-4 and TNF-α mRNA which were higher after challenge
with LPS. However in those horses that were treated with clenbuterol the LPS-induced IL-10 mRNA expression was shown to be
suppressed. Further changes in IL-4 and TNF-α were not significant. Thus the results of this study indicated that clenbuterol
can modulate the expression of IL-10 mRNA in peripheral white blood cells in those horses with small airway diseases that
have been exposed to LPS.
van den Hoven, R., Duvigneau, J.C., Hartl, R.T. and Gemeiner, M., 2006. Clenbuterol affects the expression of messenger RNA
for interleukin 10 in peripheral leukocytes from horses challenged intrabronchially with lipopolysaccharides. Veterinary Research
Communications, 30(8), 921–928 相似文献
934.
935.
Rationale and perspectives on the success of vaccination against bovine herpesvirus-1 总被引:1,自引:0,他引:1
van Drunen Littel-van den Hurk S 《Veterinary microbiology》2006,113(3-4):275-282
Several characteristics of BHV-1 have contributed to the successful development of both conventional and marker vaccines. BHV-1 is a stable virus, which grows to high titers in vitro, has a limited host range and causes acute viremic infections. Furthermore, the protective antigens, as well as the antigens that are suitable as marker, are present in the predominant virus isolates and induce significant and long-lasting immune responses, both in na?ve and in previously vaccinated animals. In many parts of the world including North-America control of BHV-1 is achieved by vaccination with conventional attenuated or inactivated vaccines. With parts of Europe being BHV-1 free, the ability to differentiate infected from vaccinated animals has become critical as a trading tool. Live and killed gE-deleted marker vaccines are now widely used in Europe, in combination with gE-based diagnostic tests to monitor cattle. However, several issues remain to be resolved. BHV-1 causes latency, which creates a need for stringent management practices in case eradication is to be achieved. Since intramuscular delivery with a syringe and needle leads to considerable tissue damage, needle-free delivery methods should be adopted for beef cattle. Furthermore, conventional inactivated and attenuated vaccines are less efficacious in neonates, so alternative vaccine types such as CpG adjuvanted protein vaccines or DNA vaccines are required for effective vaccination of this age group. 相似文献
936.
Eysker M Bakker N van der Hall YA van Hecke I Kooyman FN van der Linden D Schrama C Ploeger HW 《Veterinary parasitology》2006,141(1-2):91-100
Two experiments were performed in 2002 and 2003 to evaluate the effect of biological control of gastrointestinal nematodes in sheep through the daily feeding of 500,000 chlamydospores of Duddingtonia flagrans/kg bodyweight to lactating ewes during the first 9 weeks with their young lambs on pasture. In both experiments four groups of eight ewes and their April-borne lambs were used. They were turned out on four separate plots (plots A) at the beginning of May, moved to similar separate plots after 3 (plots B) and 6 weeks (plots C), respectively, and weaning occurred after 9 weeks. In both experiments, two groups were fed spores daily while the two other groups served as controls. The effect of D. flagrans application was evaluated through faecal egg counts of ewes and lambs, the yield of faecal cultures in ewes, pasture larval counts and worm counts of lambs and tracer lambs. The results demonstrated no effect of D. flagrans application during the first 5 (2002) or 4 (2003) weeks. Subsequently, fungus application strongly reduced the yield in faecal cultures of the ewes. This was, however, not reflected in the pasture larval counts, but lower worm burdens were observed in tracer lambs of 'treated' plots C in 2002 than on those of 'control' plots. In 2003 worm burdens in 'treated' lambs returned to plots B were lower than those of 'control' lambs and a tendency for the same was observed for plots C. However, in all groups, lambs and tracer lambs developed severe haemonchosis. 相似文献
937.
938.
939.
Hackl S van den Hoven R Zickl M Spona J Zentek J 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2006,53(9):439-444
Few data are available on post-prandial changes of plasma amino acids (AAs) in horses and on the repeatability and the individual variance on different sampling days. The objective of the present study was to measure pre- and post-prandial concentrations of plasma AA in 10 yearling horses. Blood samples were taken on days 1 and 40 of the study before feeding of hay, oats and soya meal and over an 8 h post-prandial period in 2-h intervals. The plasma AAs were measured by high-pressure liquid chromatography after ortho-phthalaldehyde derivatization. Mean fasting concentrations of the AAs were not significantly influenced by the individuum and sampling day. Repeatability of the fasting AA levels in the individual horses on two different sampling days was only found for histidine, 3-methylhistidine, methionine, tryptophan and taurine. While the absolute post-prandial AA concentrations differed between sampling days, the relative changes were comparable. All AA concentrations except 3-methylhistidine increased after feeding by 13% to more than 200% of their fasting values if the combined data of both days were analysed. Four hours after feeding the concentrations of arginine, asparagine, lysine, leucine, isoleucine and threonine, decreased more than 20%. Histidine, methionine, phenylalanine, valine, tryptophan, glutamine, glycine, tyrosine and taurine concentrations decreased by less than 20%. Concentrations of aspartic acid, glutamic acid, ornithine, serine and citrulline remained elevated. Most AA approached the fasting concentrations at 8 h, only glycine increased between 6 and 8 h after meal and 3-methyl-histidine concentrations were constant throughout the entire period. In conclusion, the pre-prandial plasma AA in horses appeared less influenced by individuum or sampling day than post-prandial plasma AA concentrations. Therefore, plasma AA concentrations should be interpreted only under well-defined conditions, especially regarding the feeding regimen. 相似文献
940.
van Geffen C Bavegems V Duchateau L De Roover K Daminet S 《Veterinary journal (London, England : 1997)》2006,172(1):135-140
Numerous factors including non-thyroidal systemic diseases and drug administration can significantly alter canine thyroid function test results. Furthermore, the importance of breed specific variations has probably been underestimated. In this study, total thyroxine (TT4), free thyroxine (FT4), canine endogenous thyroid stimulating hormone (cTSH) serum concentrations and thyroglobulin autoantibodies (TgAA) were determined in a population of healthy whippets and compared to a control group of different breeds. Mean TT4 values were significantly lower in the whippets but no significant differences were seen between whippets and control dogs for FT4 and for cTSH. The prevalence of serum TgAA in the whippets was 2%, and this was not significantly different from the controls. The results suggest a breed variation for TT4, but not for FT4, cTSH and TgAA serum concentrations in whippets. Serum thyroid hormone concentrations were also compared between trained and non-trained whippets and it was concluded that regular training did not seem to have any significant influence. 相似文献