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81.
Atxaerandio R Aduriz G Ziluaga I Esteban JI Maranda L Mainar-Jaime RC 《The Veterinary record》2005,156(12):376-380
A cross-sectional study was carried out in the Basque Country of Spain to determine the seroprevalence of 10 Leptospira serovars in a population of dairy cattle with poor fertility, and a case-control study was carried out in another northern area to investigate the role of Leptospira interrogans serovar Bratislava in abortions. L. Bratislava was the most prevalent serovar in the cross-sectional study, with 25.4 per cent of the cows testing positive in the microagglutination test when a cut-off of 1:10 or higher was applied, followed by Leptospira Hardjo (8.2 per cent), Leptospira Pomona (7.7 per cent), Leptospira Autumnalis (0.7 per cent) and Leptospira Copenhageni (0.1 per cent). In the case-control study the seroprevalence of L. Bratislava was significantly higher among the cows which had aborted when a titre of 1:300 or more was used as a cut-off (9.7 per cent v 3.4 per cent, P=0.008); 69 per cent of the L. Bratislava-infected cows that had aborted apparently aborted as a result of the infection. 相似文献
82.
Antiproliferative effects and apoptosis induction by probiotic cytoplasmic extracts in fish cell lines 总被引:1,自引:0,他引:1
Probiotic bacteria are known to exert a wide range of beneficial effects on their animal hosts. Control of intestinal homeostasis, inflammation suppression and a reduction in the incidence of cancer all rely on the antiproliferative potential of probiotics. In this paper, we assess the antiproliferative activity of probiotics in two teleost fish cell lines SAF-1, a fibroblast cell line and EPC, an epithelioma from carp. Cells were grown in the presence of cytoplasmic extracts obtained from two bacterial strains, Lactobacillus delbrüeckii subsp. lactis (LDL) and 51M6. Proliferation and apoptosis were measured after 4, 24, 48 or 72h in culture by the crystal violet or by double staining flow cytometry assays, respectively. Generally, LDL had stronger effects on cell growth than 51M6. Moreover, SAF-1 cells were more susceptible to growth inhibition than EPC cells. Apoptosis took place following growth inhibition, especially when LDL extracts were used. The results are discussed in terms of the biological significance of probiotic bacteria that naturally occur on the fish mucosal surfaces with an emphasis on how dose and species specificity may be determinant factors. 相似文献
83.
Xin Gao Yuanyuan Sun Yuehui Diao Yunpeng Zhao Rodríguez‐Leyva Esteban Guoqing Yang 《Weed Biology and Management》2020,20(2):61-68
In order to verify the escape‐from‐enemy hypothesis from the changes of nutrient substance and fitness of natural enemies on alien plants, contents of free amino acids in native and invasive plant populations of Ageratina adenophora and life history parameters of specialist herbivore Procecidochares utilis reared on these plants were investigated. Our results showed that the contents of glycine, valine, γ‐aminobutyric acid, proline, serine, alanine, and arginine in the invasive plants were higher than those in the native plants of A. adenophora. There was a shorter developmental duration and higher fecundity of P. utilis when fed on the invasive plants. The results indicated a possible fitness tradeoff of natural enemies between invasive and native plants arose from nutrient substance changes. 相似文献
84.
Arno Lindner Ramón A. López Esteban Durante Violeta Ferreira Federico M. Boffi Federico 《Journal of Equine Veterinary Science》2009
This study examined the effect of exercising horses 3 times per week with two bouts of 5-minutes' duration at their v10. Six Thoroughbreds were treadmill-conditioned for 6 weeks. A standardized exercise test (SET) was performed at the beginning of the conditioning period to determine the blood lactate–running speed (BLRS) relation, and the SET was repeated every 2 weeks. After each SET, the BLRS relation was used to calculate the horse's speed, which produced a blood lactate (LA) concentration of 10 mmol/L (v10) and 4 mmol/L (v4). Each horse was then conditioned for the next 2 weeks (3 times/week) at its individual v10 for two 5-minute bouts with a 5-minute walking phase in between. Exercise speed was individually adapted to the new v10 every 2 weeks. The v4 of horses decreased after the first 2 weeks (from 6.23 ± 0.41 m/s to 5.95 ± 0.33 m/s, mean ± SD; P < .05), increased in the following 2 weeks (6.33 ± 0.58 m/s; P < .01), and stayed constant thereafter (P > .05). The conclusion drawn was that exercising horses 3 times per week at their v10 for two 5-minute bouts did not improve v4. 相似文献
85.
S. Vázquez R. Agha A. Granado M. J. Sarro E. Esteban J. M. Peñalosa R. O. Carpena 《Water, air, and soil pollution》2006,177(1-4):349-365
Cadmium and arsenic are two of the most important and toxic pollutants ubiquitous in the environment. The occurrence of numerous polluted areas as the affected by the accident of Aznalcóllar pyrite mine has promoted the employment of the phytoremediation as a feasible technology able to control and reduce the risk of this contamination at low cost. White lupin plant is proposed as a candidate for phytoremediation. This work aims to study if it is possible to use white lupin in phytoremediation of soils affected by acid pyrite sludge, with simultaneous As and Cd pollution. Pot and field experiments with sludge-affected soil were carried out. The pot trial showed that the NTA treatment increased Cd and As concentrations in lixiviates, exceeding the maximum permissible levels, so that its use in field experiments was avoided. In the field experiment, phytoextraction of Cd and As by lupin plants was very low, suggesting that it was not recommended for phytoextraction. However, lupin culture in the field produced several benefits as: increase of acid soil pH probably by citrate excretion, decrease in soluble As and Cd fractions in soil, high concentration of As and Cd in roots with accumulation of heavy metals in root nodules. All these results support the use of Lupinus albus for phytostabilization and revegetation of the spill polluted soils. 相似文献
86.
Juan Esteban Gómez-Martínez Nélida Rodríguez-Osorio José Julián Echeverri-Zuluaga Albeiro López-Herrera 《Journal of animal physiology and animal nutrition》2021,105(2):219-231
Our goal was to define the effect of the energy intake in Holstein cows’ diet in the first third lactation on gene expression profile of immune system in mammary gland through RNA-seq. Twelve Holstein cows were used in the first third of lactation, arranged in four treatments or diets: (a) hypocaloric (HYPO, 85% of the net energy of lactation (NEl) requirements), (b) isocaloric (ISO, 100% of the NEl requirements, control diet), (c) hypercaloric (HYPER, 115% of the NEl requirements) and (d) isocaloric plus sunflower oil supplementation (OIL, 106% of the NEl requirements). A biopsy of mammary gland tissue was carried out after 25 days per diet, from which the RNA was extracted and sequenced using the Illumina HiSeqTM 2,500 sequencer. The analysis of reads obtained from the sequencing in the QIAGEN® CLC Genomics Workbench 10.0 bioinformatics software was performed. From 27,368 genes annotated in the reference genome, 17,429 genes expressed in the evaluated treatments were identified. Moreover, 1,743 differentially expressed genes (DEGs) were found, of which 15 DEGs were found in the ISO vs. OIL comparison, 1,196 DEGs in the ISO vs. HYPO comparison and 532 DEGs in the ISO vs. HYPER comparison. Thus, of the 1,743 DEGs, 401 correspond to genes involved in the functioning of the immune system, encompassing 23% of the total number of DEGs involved in the analysis, and 13.6% of the total number of genes involved in the functioning of the immune system. The energy intake in Holstein cows’ diet has impact in the expression of immune genes CXCL13, TRDC among others, present in the regulation of immune system processes. This immune system altered might increase the somatic cells score and therefore reach some diseases. It is recommended to measure the energy intake according to the animals’ energy requirements and to cover them the closest to the 100%. 相似文献
87.
Both human and nonhuman decision-makers can deviate from optimal choice by making context-dependent choices. Because ignoring context information can be beneficial, this is called a "less-is-more effect." The fact that organisms are so sensitive to the context is thus paradoxical and calls for the inclusion of an ecological perspective. In an experiment with starlings, adding cues that identified the context impaired performance in simultaneous prey choices but improved it in sequential prey encounters, in which subjects could reject opportunities in order to search instead in the background. Because sequential prey encounters are likely to be more frequent in nature, storing and using contextual information appears to be ecologically rational on balance by conditioning acceptance of each opportunity to the relative richness of the background, even if this causes context-dependent suboptimal preferences in (less-frequent) simultaneous choices. In ecologically relevant scenarios, more information seems to be more. 相似文献
88.
Rojas-Gómez Mónica Jiménez-Madrigal Jose Pablo Montero-Vargas Maripaz Loaiza-Montoya Randall Chavarría Max Meneses Esteban Fuchs Eric J. 《Genetic Resources and Crop Evolution》2022,69(1):39-47
Genetic Resources and Crop Evolution - Psidium friedrichsthalianum (O. Berg) Nied. is a tropical tree species in the Myrtaceae family, natively distributed from southern Mexico to eastern Venezuela... 相似文献
89.
Hermo GA Turic E Angelico D Scursoni AM Gomez DE Gobello C Alonso DF 《Journal of the American Animal Hospital Association》2011,47(1):21-27
Desmopressin (DDAVP) is a vasopressin peptide analog with hemostatic properties that has been successfully used during surgery in patients with bleeding disorders. Recently published experimental and clinical data indicate that perioperative administration of DDAVP can minimize spread and survival of residual mammary cancer cells. The central aim of this study was to explore the effect of perioperative DDAVP and its relation to histologic grade in bitches with locally advanced mammary carcinoma. Of the 32 dogs initially recruited, 28 intact bitches with mammary carcinoma tumors stage III or IV were ultimately included. These dogs were randomized to receive DDAVP at intravenous doses of 1 μg/kg (n=18) or saline solution as placebo (n=10). En bloc mastectomy of the affected gland(s) was performed. Tumor malignancy was graded by the method of Elston and Ellis into well-differentiated (grade 1), moderately differentiated (grade 2), or poorly differentiated (grade 3). DDAVP therapy significantly prolonged the disease-free survival (P<0.001) and overall survival (P<0.01) in bitches with grade 2 or 3 carcinomas compared with bitches in the control group. No significant difference in disease-free period or overall survival was found between treatment groups in bitches with grade 1 tumors. The present data suggest that DDAVP may be an excellent candidate as a surgical adjuvant in the management of aggressive cancers in small animals. More research in this field is warranted. 相似文献
90.
Trading water for carbon with biological carbon sequestration 总被引:4,自引:0,他引:4
Jackson RB Jobbágy EG Avissar R Roy SB Barrett DJ Cook CW Farley KA le Maitre DC McCarl BA Murray BC 《Science (New York, N.Y.)》2005,310(5756):1944-1947
Carbon sequestration strategies highlight tree plantations without considering their full environmental consequences. We combined field research, synthesis of more than 600 observations, and climate and economic modeling to document substantial losses in stream flow, and increased soil salinization and acidification, with afforestation. Plantations decreased stream flow by 227 millimeters per year globally (52%), with 13% of streams drying completely for at least 1 year. Regional modeling of U.S. plantation scenarios suggests that climate feedbacks are unlikely to offset such water losses and could exacerbate them. Plantations can help control groundwater recharge and upwelling but reduce stream flow and salinize and acidify some soils. 相似文献