Application of a plant bioassay for the evaluation of ecotoxicological risks of heavy metals in sediments affected by mining activities     

Mari Luz García-Lorenzo  María José Martínez-Sánchez  Carmen Pérez-Sirvent 《Journal of Soils and Sediments》2014,14(10):1753-1765

Purpose

The objective of this work was to evaluate the effectiveness of a plant bioassay (Phytotoxkit®) for screening ecotoxicological risks in sediments affected by mining activities.

Materials and methods

A total of 42 sediment samples affected by mining activities were studied, including 39 sediment samples from the Sierra Minera, Spain, an area affected by old extraction procedures, and three sediments from an area affected by opencast mining. These three samples were then mixed with limestone filler at 10, 20 and 30 %, providing nine stabilised samples. The total and soluble metal(loid) content (As, Cd, Cu, Fe, Pb and Zn) was determined in all samples, and the Phytotoxkit® bioassay was applied to determine the ecotoxicological effect of this procedure.

Results and discussion

The stabilised material had a neutral pH and low soluble metal(loid) concentration, similar to that of samples in which a natural attenuation process had taken place because of mixing with surrounding carbonate-rich materials. An ecotoxicological survey identified the low toxicity levels of the stabilised samples.

Conclusions

The applied bioassay is a good tool for screening metal(loid) contamination in areas affected by mining activities, since it provides information on both natural and simulated attenuation processes. The mixing of sediments with limestone filler could be applied to the remediation of zones affected by mining activities, because the toxicological effect on the tested organisms in the stabilised sediments was reduced significantly and the metal(loid) content was diminished.  相似文献   

Encapsulated nitrate replacing soybean meal changes in vitro ruminal fermentation and methane production in diets differing in concentrate to forage ratio     

Andressa Santanna Natel  Adibe Luiz Abdalla  Rafael Canonenco de Araujo  Concepta McManus  Tiago do Prado Paim  Adibe Luiz de Abdalla Filho  Patrícia Louvandini  Carina Nazato 《Animal Science Journal》2019,90(10):1350-1361

The objective of this study was to evaluate the effects of using encapsulated nitrate product (ENP) replacing soybean meal in diets differing in concentrate to forage ratio on ruminal fermentation and methane production in vitro using a semi‐automatic gas production technique. Eight treatments were used in a randomized complete design with a 2 × 4 factorial arrangement: two diet (20C:80F and 80C:20F concentrate to forage ratio) and four levels of ENP addition (0%, 1.5%, 3.0%, and 4.5% of DM) replacing soybean meal. There was a diet × ENP interaction (p = 0.02) for methane production. According to ENP addition, diets with 80C:20F showed more intense reduction on methane production that 20C:80F. A negative linear effect was observed for propionate production with ENP addition in diet with 80C:20F and to the relative abundance of methanogens Archaea, in both diet. The replacement of soybean meal by ENP in levels up to 3% of DM inhibited methane production due to a reduction in the methanogens community without affecting the organic matter degradability. However, ENP at 4.5% of DM level affected fiber degradability, abundance of cellulolytic bacteria, and propionic acid production, indicating that this level of inclusion is not recommended for ruminant production.  相似文献   

Occurrence of Pythium Ultimum Var. Ultimum in a Greenhouse on Spitsbergen Island, Svalbard     

Motoaki Tojo  Tamotsu Hoshino  María Luz Herrero  Sonja Sletner Klemsdal  Anne Marte Tronsmo 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(7):761-765

Pythium ultimum var. ultimum was isolated from carrot seedlings with damping off and from soil used for growing the plant in a greenhouse on Spitsbergen Island, Svalbard. The fungus caused severe damping off of carrot, cucumber and tomato seedlings after artificial inoculation. The rDNA internal transcribed spacer sequences of the Svalbard isolate were identical to those of Canadian and Japanese isolates of P. ultimum var. ultimum. The results suggest that the pathogen in the greenhouse on Svalbard was probably introduced from temperate regions through contaminated plants and/or soil imported to the island. This is the first record of P. ultimum var. ultimum within the Arctic zone.  相似文献   

Energy and protein requirements of non-descript breed hair lambs of different sex classes in the semiarid region of Brazil     

Rafael Torres de Souza Rodrigues  Mario Luiz Chizzotti  Samara Rodrigues Martins  Ivonete Ferreira da Silva  Mário Adriano Ávila Queiroz  Tiago Santos Silva  Karina Costa Busato  Aderbal Marcos de Azevêdo Silva 《Tropical animal health and production》2016,48(1):87-94

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Intake and digestibility,rumen fermentation,and concentrations of metabolites in steers fed with peanut cake     

Paulo Andrade de Oliveira  Ronaldo Lopes Oliveira  Soraya Maria Palma Luz Jaeger  Meiby Carneiro de Paula Leite  Adriana Regina Bagaldo  Leilson Rocha Bezerra  Braulio Rocha Correia  Nivaldo Barreto de Santana Filho 《Tropical animal health and production》2016,48(2):403-409

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Performance,nitrogen balance and microbial efficiency of beef cattle under concentrate supplementation strategies in intensive management of a tropical pasture     

Tiago Cunha Rocha  Carlos Augusto de Alencar Fontes  Renata Tavares Soares da Silva  Elizabeth Fonsêca Processi  Felipe Roberto Amaral Ferreira do Valle  Cláudio Teixeira Lombardi  Ronaldo Lopes Oliveira  Leilson Rocha Bezerra 《Tropical animal health and production》2016,48(3):673-681

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Effect of red propolis extract isolated or encapsulated in nanoparticles on the in vitro culture of sheep preantral follicle: Impacts on antrum formation,mitochondrial activity and glutathione levels     

Tiago S. Nascimento  Isabelle S. M. Silva  Maria Cecília M. A. Alves  Bruna B. Gouveia  Lara Mariane R. Barbosa  Taís J. S. Macedo  Jamile M. S. Santos  Alane P. O. Monte  Maria Helena T. Matos  Francine F. Padilha  Isabel B. Lima‐Verde 《Reproduction in domestic animals》2019,54(1):31-38

This study aimed to characterize the hydroethanolic extract of red propolis (HERP) and nanoparticles containing HERP for using as an additive in the culture medium of isolated ovine preantral follicles. HERP was characterized by high‐performance liquid chromatography (HPLC) and determination of flavonoid content, and the nanoparticles by the mean particle diameter, polydispersity index (PI) and encapsulation efficiency (EE). The effect of HERP (10 and 20 ηg/ml—HERP10 and HERP20 groups) and nanoparticles (NP10 and NP20 groups) on isolated secondary follicles cultured in vitro for 12 days was observed by morphological evaluation, oxidative stress markers (reactive oxygen species—ROS and glutathione—GSH) and active mitochondria. HPLC showed formononetin as the major compound in the HERP (63.92 ± 0.21 μg/mL). The content of flavonoids ranged from 2.14% to 11.00%. The nanoparticles showed mean diameter of 287.5 ± 3.9 and 479 ± 18.1 ηm; PI of 0.117 ± 0.018 and 0.316 ± 0.039; and EE of 67.15% and 41%, respectively, for the NP10 and NP20 groups. After 12 days of culture, HERP20 and NP20 increased (p < 0.05) the percentage of normal follicles compared to NP10. HERP20 showed significantly higher percentages of antrum formation than control medium (MEM) and NP10 (p < 0.05). HERP20 also showed an increase (p < 0.05) in mitochondrial activity compared to the other treatments, except NP20 (p > 0.05), and increased GSH levels (p < 0.05) compared to MEM and HERP10. In conclusion, use of HERP (20 ηg/ml) on in vitro culture of isolated ovine preantral follicles can increase antrum formation, mitochondrial activity and GSH levels.  相似文献   

Prevalence of lameness and hoof lesions in all year-round grazing cattle in Brazil     

Tiago Facury Moreira  Rafael Romero Nicolino  Leandro Silva de Andrade  Elias Jorge Facury Filho  Antônio Ultimo de Carvalho 《Tropical animal health and production》2018,50(8):1829-1834

Lameness is a growing concern to the dairy industry worldwide. However, little is known about lameness and its causes in grazing cattle, especially in tropical climates. This study aimed to assess the prevalence of hoof lesions and lameness in dairy herds of all year-round grazing cattle under tropical condition, and to identify the main lesions associated with lameness. We visited 48 farms located in the Minas Gerais state, Brazil, equally divided into four groups based on daily milk production. All lactating cows in the visited farms were locomotion scored, and a representative sample was randomly chosen for hoof inspection. Among the 2267 lactating cows evaluated, 16% were scored as lame and 7% as severely lame. Nearly all cows presented at least one type of hoof lesion, of which heel horn erosion (90%), white line fissure (50%), and digital dermatitis (33%) were the most prevalent. Heel horn erosion was present in all farms and digital dermatitis was present in 96% of the farms. Sole ulcer was observed in a single animal. Additionally, digital dermatitis and white line fissure were correlated to a 2.5 times increase in the odds of a poor mobility score. Collectively, our results demonstrate that digital dermatitis and white line fissure are the main concern and the biggest cause of lameness in grazing cattle under tropical conditions.  相似文献   

Performance of dual and triple fungicide premixes for managing soybean rust across years and regions in Brazil: A meta-analysis     

Jhonatan P. Barro  Kaique S. Alves  Cláudia V. Godoy  Alfredo R. Dias  Carlos A. Forcelini  Carlos M. Utiamada  Edson R. de Andrade Júnior  Fernando C. Juliatti  Fernando J. Grigolli  Heraldo R. Feksa  Hercules D. Campos  Ione C. P. V. Chaves  Ivan P. Araújo Júnior  João Mauricio T. Roy  José Nunes Júnior  Luana M. R. Belufi  Luciana C. Carneiro  Luís H. C. P. Silva  Marcelo G. Canteri  Marcio M. Goussain Júnior  Marina Senger  Maurício C. Meyer  Moab D. Dias  Mônica A. Müller  Mônica C. Martins  Mônica P. Debortoli  Nédio R. Tormen  Silvânia H. Furlan  Tiago F. Konageski  Valtemir J. Carlin  Wilson S. Venâncio  Emerson M. Del Ponte 《Plant pathology》2021,70(8):1920-1935

Soybean rust in Brazil is currently controlled with several commercial fungicide premixes composed of demethylation inhibitors (EPOXiconazole, CYPRoconazole, PROThioconazole, TEBUconazole), quinone-outside inhibitors (AZOXystrobin, TriFLoXystrobin, PYRAclostrobin, PICOxystrobin), and succinate demethylation inhibitors (BENZovindiflupyr, BIXaFen, FLUXapyroxad). Here, we summarize the performance of eight premixes evaluated in 177 cooperative trials conducted in 46 locations across 10 states from 2015 to 2020. All fungicide treatments were sprayed three times starting at R1/R2. Percentage control (, %), from back-transforming meta-analytic estimates of the log of the ratio, ranged from 56.2% (PICO + CYPR) to 76.8% (BIXF + TFLX + PROT). Estimates of mean yield difference (, kg/ha) between fungicide-treated and untreated plots were greatest for BIXF + TFLX + PROT (1,080) followed by PICO + BENZ (1,010), PYRA + EPOX + FLUX (981.5), AZOX + BENZ (910), TFLX + PROT (891), PICO +TEBU (682), TFLX + CYPR (646), and PICO + CYPR (600). Significant declines in both and in as little as 4 years were detected for AZOX + BENZ (35.3%; 550 kg/ha) and PICO + BENZ (15.5%; 359.8 kg/ha). Variance in was reduced by the inclusion of baseline severity as covariate. In trials where baseline disease was ≥70%, yield was 250 kg/ha greater compared to areas with low baseline disease. Disease control and yield response were generally greater in the south-east, where the frequency of profitable scenarios was 30% higher on average than in the north-west. Results of this meta-analysis are critical for supporting decisions during planning of fungicide programmes.  相似文献   

The CGIAR Virtual Library: A Vital Tool to Enhance Access to Agricultural Research     

Mila M. Ramos  Luz Marina Alvare  Peter Shelton  Hugo Besemer 《Journal Of Agricultural & Food Information》2013,14(1):27-36

Literature searching instruments are available via the Internet, but one has to conduct several individual searches to retrieve relevant scholarly materials for research. This scenario led information experts from the Consultative Group on International Agricultural Research (CGIAR) to find ways to make life easier for scientists. The collaboration among Information and IT managers resulted in the launch of the CGIAR Virtual Library (CGVLibrary) in 2006. CGIAR supports 15 diverse international centers, located worldwide, which generate scholarly research results that are considered as public goods and must be shared freely with the international community. The CGVLibrary enables federated searching of catalogs and databases and carries hyperlinks to full-text CGIAR documents. This article provides an analysis of the content of the CGVLibrary, of the various information avenues it opens for improving access to agricultural research, and of how the tool is being improved and marketed to promote awareness and worldwide use.  相似文献