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61.
Monalisa S. M. Souto Fernanda M. Coura Elaine M. S. Dorneles Ana Paula R. Stynen Telma M. Alves Jordana Almeida Santana Rebeca B. Pauletti Roberto M. C. Guedes Aline M. Viott Marcos B. Heinemann Andrey P. Lage 《Tropical animal health and production》2017,49(1):13-23
The aims of the present study were to determine (i) the profiles of phylogroup and (ii) the antimicrobial susceptibility of pathogenic Escherichia coli strains isolated from calves, and of Salmonella spp. strains isolated from calves and pigs in Minas Gerais State, Brazil. Sixty-one pathogenic E. coli strains and Salmonella spp. (n?=?24) strains isolated from fecal samples of calves and Salmonella spp. (n?=?39) strains previously isolated from fecal samples of growing/finishing pigs were tested. The minimum inhibitory concentration (MIC) using the agar dilution method was determined for nalidixic acid, amikacin, amoxicillin, ampicillin, cefoxitin, norfloxacin, gentamicin, tetracycline, and trimethoprim-sulfamethoxazole. All E. coli isolates were susceptible to amikacin. Tetracycline was the antimicrobial that presented the higher frequency of resistance among E. coli strains, followed by ampicillin, trimethoprim-sulfamethoxazole, amoxicillin, nalidixic acid, norfloxacin, gentamicin, and cefoxitin. E. coli (n?=?61) strains isolated from calves belonged to different phylogroup namely, phylogroup A (n?=?26), phylogroup B1 (n?=?31), phylogroup E (n?=?3), and phylogroup F (n?=?1). Phylogroups B2, C, and D were not identified among the E. coli in the present study. All Salmonella spp. (n?=?24) strains isolated from fecal samples of calves were susceptible to amikacin, amoxicillin, ampicillin, norfloxacin, gentamicin, tetracycline, and trimethoprim-sulfamethoxazole. Resistance to nalidixic acid and cefoxitin was detected in 16.66 and 8.33 % of the Salmonella spp. strains, respectively. Among the Salmonella spp. (n?=?39) strains isolated from fecal samples of pigs, the higher frequency of resistance was observed to tetracycline, followed by amoxicillin, gentamicin, ampicillin, trimethoprim-sulfamethoxazole, nalidixic acid, cefoxitin, and norfloxacin. All strains were susceptible to amikacin. Forty-eight (78.68 %) of the E. coli strains were classified as multidrug-resistant, whereas among Salmonella spp. strains, the percentage of multidrug resistance was 57.14 %, being all multidrug-resistant strains isolated from pigs (92.30 %). The results from the present study indicate a high frequency of antimicrobial resistance among pathogenic E. coli strains isolated from calves and Salmonella spp. strains isolated from pigs and a high rate of susceptibility to most antimicrobials tested among Salmonella spp. strains isolated from calves. Our study highlights the presence of multidrug-resistant strains of E. coli and Salmonella spp. isolated from food-producing animals in Minas Gerais, Brazil. 相似文献
62.
Tito Bacca Khalid Haddi Maria Pineda Raul Narciso C Guedes Eugênio E Oliveira 《Pest management science》2017,73(2):i-i
The cover image, by Eugênio E. Oliveira et al., is based on the Research Article Pyrethroid resistance is associated with a kdr‐type mutation (L1014F) in the potato tuber moth Tecia solanivora, DOI: 10.1002/ps.4414 . Photo Credit: Edison Torrado‐Leon.
63.
R. S. Fagundes M. A. Uribe-Opazo M. Galea L. P. C. Guedes 《Journal of Agricultural, Biological & Environmental Statistics》2018,23(2):276-296
This article studies the dependence of spatial linear models using a slash distribution with a finite second moment. The parameters of the model are estimated with maximum likelihood by using the EM algorithm. To avoid identifiability problems, the cross-validation, the Trace and the maximum log-likelihood value are used to choose the parameter for adjusting the kurtosis of the slash distribution and the selection of the model to explain the spatial dependence. We present diagnostic techniques of global and local influences for exploring the sensibility of estimators and the presence of possible influential observations. A simulation study is developed to determine the performance of the methodology. The results showed the effectiveness of the choice criteria of the parameter for adjusting the kurtosis and for the selection of the spatial dependence model. It has also showed that the slash distribution provides an increased robustness to the presence of influential observations. As an illustration, the proposed model and its diagnostics are used to analyze an aquifer data. The spatial prediction with and without the influential observations were compared. The results show that the contours of the interpolation maps and prediction standard error maps showed low changes when we removed the influential observations. Thus, this model is a robust alternative in the spatial linear modeling for dependent random variables. Supplementary materials accompanying this paper appear online. 相似文献
64.
Alonso G.P. Guedes Caitlin C. Tearney Alessia Cenani Fabio Aristizabal Jorge Nieto 《Veterinary anaesthesia and analgesia》2017,44(2):273-280
Objective
To compare postanesthetic xylazine and dexmedetomidine on recovery characteristics from sevoflurane anesthesia in horses.Study design
Randomized, crossover study.Animals
Six geldings, mean ± standard deviation (SD) (range), 17 ± 4 (11–24) years and 527 ± 80 (420–660) kg.Methods
Horses were anesthetized with sevoflurane for 60 minutes under standardized conditions for a regional limb perfusion study. In recovery, horses were administered either xylazine (200 μg kg?1) or dexmedetomidine (0.875 μg kg?1) intravenously. Recoveries were unassisted and were video-recorded for later evaluation of recovery events and quality by two individuals unaware of treatment allocation. Recovery quality was assessed using a 100 mm visual analog scale (VAS) (0 = poor recovery, 100 = excellent recovery), the Edinburgh Scoring System (ESS) (0–100; 100 = excellent recovery) and the mean attempt interval (MAI) (longer = better). Data are mean ± SD.Results
All recovery quality assessments (xylazine and dexmedetomidine, respectively: VAS: 71 ± 21 mm, 84 ± 13 mm; ESS: 65 ± 22, 67 ± 30; MAI: 52 ± 24 minutes, 60 ± 32 minutes) and events (first limb movement: 37 ± 8 minutes, 42 ± 10 minutes; first attempt to lift head: 44 ± 12 minutes, 48 ± 9 minutes; first attempt to sternal posture: 57 ± 28 minutes, 50 ± 7 minutes; number of head bangs: 2.0 ± 3.0, 0.5 ± 0.5; time to first attempt to stand: 72 ± 6 minutes, 78 ± 13 minutes; time to standing: 79 ± 14 minutes, 84 ± 13 minutes) did not differ significantly between treatments (p > 0.05).Conclusions and clinical relevance
Recovery characteristics did not differ significantly between postanesthetic xylazine and dexmedetomidine following 1 hour of sevoflurane anesthesia in horses in this study. Further evaluations in more horses and in younger horses are required to confirm these results. 相似文献65.
V. F. Silva G. V. França J. W. S. Melo R. N. C. Guedes M. G. C. Gondim Junior 《Journal of pest science》2017,90(1):207-215
The control of hidden pest species with pesticides depends on the accurate timing of the application to reach the life stages during their only moment of vulnerability, which is when the pests (temporarily) leave their hiding places. A curious case involves the colonization of the coconut perianth, a bract-protected region of the fruit, by the coconut mite Aceria guerreronis. The coconut bracts apparently provide protection against the direct action of acaricides used against the coconut mite. Furthermore, some acaricides target mite eggs and/or immatures in addition to adults, leading to enhanced mortality and/or compromised progeny production, but only if reaching these stages. In this study, we developed methods for assessing the likely protection provided by the coconut bract against the acaricides used for managing the coconut mite. We also assessed the efficacy of the acaricides currently registered for use against this species. Our results support the notion that coconut bracts provide protection to the coconut mite against direct acaricide action. Some acaricides (abamectin and fenpyroximate) were effective only with the removal of the coconut bracts, whereas others (hexythiazox and spirodiclofen) were not effective even with bract removal. Coconut mites sheltered by bracts were protected against the acaricides over time, but the acaricides seemed to induce mite dispersion. In addition, the preventive application of some acaricides reduced the chances of the perianth colonization by the coconut mite. Among the acaricides used, two (hexythiazox and spirodiclofen) are registered as ovicides, but only one (spirodiclofen) acted on eggs, preventing hatching of approximately 40 % of the eggs. The acaricide impacts on coconut mite management are discussed. 相似文献
66.
Isabel Correia Alexandra NunesSofia Guedes António S. BarrosIvonne Delgadillo 《Journal of Cereal Science》2010
A screening of commercial lactic acid bacteria potentially useful in the improvement of sorghum nutritional quality was done. The aim of this study was to test starter cultures to meet the prerequisites for the establishment of small-scale industrial production of sorghum fermented foods in Africa. 相似文献
67.
Patrícia Mendon?a Pauletti Lucas Silva Cintra Caio Guedes Braguine Ademar Alves da Silva Filho Márcio Luís Andrade e Silva Wilson Roberto Cunha Ana Helena Januário 《Marine drugs》2010,8(5):1526-1549
This review discusses the isolation, structural elucidation, and biological activities of halogenated indole alkaloids obtained from marine invertebrates. Meridianins and related compounds (variolins, psammopemmins, and aplicyanins), as well as aplysinopsins and leptoclinidamines, are focused on. A compilation of the 13C-NMR spectral data of these selected natural indole alkaloids is also provided. 相似文献
68.
Oliveira CM Ferreira AC de Pinho PG Silva AM 《Journal of agricultural and food chemistry》2008,56(21):10326-10331
The aim of this study was to obtain new information on antioxidant compounds in white wines. For this purpose, white wine degradation was promoted by a forced aged protocol, and six normally aged white wines from different vintages were analyzed. Both normal and forced aged wines were sequentially extracted using hexane and ethyl acetate. Apolar antioxidants were removed using hexane, and polar antioxidants were extracted with ethyl acetate. This last residue was subject to partial re-extraction with hexane and acetone. The antioxidant capacity of the wines and of each fraction was evaluated by two free radical methods, ABTS and DPPH. Normal aging provides a decrease in the total antioxidant capacity of wines. The antioxidant activity of ethyl acetate/acetone extracts was approximately 95% higher than that found for the hexane extracts. Concerning the forced aged wines, results showed that the wine submitted to a temperature of 60 degrees C for 21 days had higher antioxidant activity than that submitted to a temperature of 20 degrees C. With regard to the ethyl acetate/acetone extracts, oxygen and temperature treatment leads to a decrease in their antioxidant activity. NMR analysis was performed in the highest antioxidant capacity organic fractions (ethyl acetate/acetone extracts) and in the aqueous fraction of the control wine (T = 20 degrees C), in order to attempt the characterization of species involved in oxygen protection. Possible structures of antioxidant compounds in white wines were proposed. Two of these are tyrosol-like structures. This molecule is a well-known phenolic compound in wine, and it is reported to have antioxidative effects. 相似文献
69.
Assessing the spatial distribution of Tuta absoluta (Lepidoptera: Gelechiidae) eggs in open‐field tomato cultivation through geostatistical analysis 下载免费PDF全文
70.