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81.
Oyama MA Sisson DD Prosek R Bulmer BJ Luethy MW Fuentes VL 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(6):1272-1279
BACKGROUND: Dilated cardiomyopathy (DCM) is characterized by reduced systolic function, heightened sympathetic tone, and high morbidity and mortality. Little is known regarding the safety and efficacy of beta-blocker treatment in dogs with DCM. HYPOTHESIS: Carvedilol improves echocardiographic and neurohormonal variables in dogs with DCM over a 4-month treatment period. METHODS: Prospective, placebo-controlled, double-blinded randomized study. Dogs with DCM underwent echocardiography, ECG, thoracic radiographs, and neurohormonal profiling, followed by titration onto carvedilol (0.3 mg/kg q12h) or placebo over a 4-week period and subsequently received 3 months of therapy. Primary study endpoints included left ventricular volume and function. RESULTS: Sixteen dogs received carvedilol and 7 received placebo. At study end, 13 carvedilol dogs and 5 placebo dogs were alive. There was no difference in the mean percentage change in left ventricular volume at end-diastole (LVVd), left ventricular end-systolic volume (LVVs), and ejection fraction (EF) between treatment groups, suggesting that both groups experienced similar amounts of disease progression. Carvedilol treatment did not result in significant changes in neurohormonal activation, radiographic heart size, heart rate, or owner perceived quality-of-life. Baseline B-type natriuretic peptide (BNP) predicted dogs in the carvedilol-treated group that maintained or improved their EF over the study duration. CONCLUSIONS AND CLINICAL IMPORTANCE: Carvedilol administration did not improve echocardiographic or neurohormonal indicators of heart function. The lack of effect may be related to severity of disease, carvedilol dose, or brevity of follow-up time. Statistical power of the present study was adversely affected by a high fatality rate in study dogs and small sample size. 相似文献
82.
Nielsen L Toft N Eckersall PD Mellor DJ Morris JS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(6):1231-1236
BACKGROUND: The acute-phase protein C-reactive protein (CRP) is used as a diagnostic and prognostic marker in humans with various neoplasias, including non-Hodgkin's lymphoma. OBJECTIVE: To evaluate if CRP could be used to detect different remission states in dogs with lymphoma. ANIMALS: Twenty-two dogs with untreated multicentric lymphoma. METHODS: Prospective observational study. Blood samples were collected at the time of diagnosis, before each chemotherapy session, and at follow-up visits, resulting in 287 serum samples. RESULTS: Before therapy, a statistically significant majority of the dogs (P = .0019) had CRP concentrations above the reference range (68%, 15/22). After achieving complete remission 90% (18/20) of the dogs had CRP concentrations within the reference range, and the difference in values before and after treatment was statistically significant (P < .001). CRP concentrations of dogs in complete remission (median, 1.91; range, 0.2-103) were significantly different (P = .031) from those of dogs with partial remission (median, 2.48; range, 0-89), stable disease (median, 1.77; range, 1.03-42.65), or progressive disease (median, 8.7; range, 0-82.5). There was profound variation of CRP measurements within each dog. CONCLUSIONS: CRP is useful in determining complete remission status after treatment with cytotoxic drugs. However, the individual variation between dogs means CRP concentration is not sufficiently different in other remission states to permit its use in monitoring progression of the disease. Greater reliability in determining remission status might be achieved by combining CRP concentration with other serum markers. 相似文献
83.
Gardner IA Wong SJ Ferraro GL Balasuriya UB Hullinger PJ Wilson WD Shi PY MacLachlan NJ 《Veterinary research》2007,38(1):109-116
A prospective cohort study was used to estimate the incidence of West Nile virus (WNV) infection in a group of unvaccinated horses (n = 37) in California and compare the effects of natural WNV infection in these unvaccinated horses to a group of co-mingled vaccinated horses (n = 155). Horses initially were vaccinated with either inactivated whole virus (n = 87) or canarypox recombinant (n = 68) WNV vaccines during 2003 or 2004, prior to emergence of WNV in the region. Unvaccinated horses were serologically tested for antibodies to WNV by microsphere immunoassay incorporating recombinant WNV E protein (rE MIA) in December 2003, December 2004, and every two months thereafter until November 2005. Clinical neurologic disease attributable to WNV infection (West Nile disease (WND)) developed in 2 (5.4%) of 37 unvaccinated horses and in 0 of 155 vaccinated horses. One affected horse died. Twenty one (67.7%) of 31 unvaccinated horses that were seronegative to WNV in December, 2004 seroconverted to WNV before the end of the study in November, 2005. Findings from the study indicate that currently-available commercial vaccines are effective in preventing WND and their use is financially justified because clinical disease only occurred in unvaccinated horses and the mean cost of each clinical case of WND was approximately 45 times the cost of a 2-dose WNV vaccination program. 相似文献
84.
Rubber mats covering concrete slatted flooring are a developing market in dairy barns but remain rare in beef cattle facilities. The aim of this study was to investigate the effects of covering slatted concrete floor with perforated rubber mats on behaviour and occurrence of skin and claw lesions in fattening bulls. The groups of six bulls each with a total average age of 9.8 months were kept over 1 year on either slatted concrete (CONCRETE PEN) or on slatted concrete covered completely (RUBBER PEN) or partially (CHOICE PEN) with perforated rubber mats. Every quarter-year, behaviour (preference of flooring, lying, aggression, mounting) was recorded. In two-weekly intervals the incidence of skin lesions was examined. At 12 and 18 months of age the rising time of the bulls was measured. At the beginning of the study and after slaughter claw dimensions were recorded. Bulls in the CHOICE PEN preferred (P<0.01) the rubber coated area throughout the experiment. Animals in the RUBBER and the CHOICE PENS showed more lying periods (P<0.01) and had a lesser incidence of skin lesions (P<0.01) compared to bulls in the CONCRETE PEN. Bulls in the CHOICE PEN needed less time for rising (2.7+/-0.3s) than bulls in the CONCRETE PEN (4.4+/-0.5s, P<0.01). Net claw growth differed significantly between all pens (RUBBER>CHOICE>CONCRETE; P<0.05). In conclusion, the results of this study indicate that rubber coated slatted flooring has a positive influence on the housing conditions of beef cattle. 相似文献
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87.
Sandra R. Ethridge Saket Chandra Anna M. Locke Wesley J. Everman David L. Jordan Micheal D.K. Owen Ramon G. Leon 《Pest management science》2023,79(10):4048-4056
BACKGROUND
The potential of weed species to respond to selection forces affecting the evolution of weedy traits such as competitive ability is poorly understood. This research characterized evolutionary growth changes in a single Abutilon theophrasti Medik. population comparing multiple generations collected from 1988 to 2016. A competition study was performed to understand changes in competitive ability, and a herbicide dose–response study was carried out to assess changes in sensitivity to acetolactate synthase-inhibiting herbicides and glyphosate over time.RESULTS
When grown in monoculture, A. theophrasti biomass production per plant increased steadily across year-lines while leaf number decreased. In replacement experiments, A. theophrasti plants from newer year-lines were more competitive and produced more biomass and leaf area than the oldest year-line. No clear differences in sensitivity to imazamox were observed among year-lines. However, starting in 1995, this A. theophrasti population exhibited a progressive increase in growth in response to a sublethal dose of glyphosate (52 g a.e. ha−1), with the 2009 and 2016 year-lines having more than 50% higher biomass than the nontreated control.CONCLUSION
This study demonstrates that weeds can rapidly evolve increased competitive ability. Furthermore, the results indicate the possibility of changes in glyphosate hormesis over time. These results highlight the importance of the role that rapid (i.e., subdecadal) evolution of growth traits might have on the sustainability of weed management strategies. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献88.
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90.
Marco Grella Fabrizio Gioelli Paolo Marucco Ingrid Zwertvaegher Eric Mozzanini Marco Pittarello Paolo Balsari Spyros Fountas David Nuyttens Monica Mezzalama Massimo Pugliese 《Pest management science》2023,79(11):4423-4438